Patent Publication Number: US-2015080777-A1

Title: Weight-bearing lower extremity brace

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/879,127 filed Sep. 17, 2013. The contents of all of the above are hereby incorporated in their entirety by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates, according to some embodiments, to methods, devices, and systems for ambulation of a subject having an impaired lower extremity. 
     BACKGROUND OF THE DISCLOSURE 
     Subjects unable to support their own weight due to a lower extremity impairment may resort to crutches or wheel chairs to move about. However, crutches and wheel chairs may be undesirable because of the limitations they impose on a subject&#39;s ability to use their hands. In addition, crutches and/or wheel chairs may incompletely restore mobility, and/or may be untenable in an older person due to decreased upper body strength and/or poor balance in the case of crutches. 
     SUMMARY 
     Accordingly, a need has arisen for improved ambulatory devices for subjects with impairments of the lower extremities. The present disclosure relates, according to some embodiments, to methods, devices, and systems for ambulation of a subject having an impaired lower extremity. For example, a device may comprise a lower extremity brace configured to bear a subject&#39;s weight and/or transfer the load to unimpaired organs and/or tissues. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Some embodiments of the disclosure may be understood by referring, in part, to the present disclosure and the accompanying drawings, wherein: 
         FIG. 1A  illustrates a generally isometric view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 1B  illustrates a left profile view of the device for ambulation of a subject shown in  FIG. 1A  according to a specific example embodiment of the disclosure; 
         FIG. 1C  illustrates a right profile view of the device for ambulation of a subject shown in  FIG. 1A  according to a specific example embodiment of the disclosure; 
         FIG. 1D  illustrates a front view of the device for ambulation of a subject shown in  FIG. 1A  according to a specific example embodiment of the disclosure; 
         FIG. 2A  illustrates a generally isometric view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 2B  illustrates a generally isometric view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 3A  illustrates a generally isometric view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 3B  illustrates a left profile view of the device for ambulation of a subject shown in  FIG. 3A  according to a specific example embodiment of the disclosure; 
         FIG. 3C  illustrates a right profile view of the device for ambulation of a subject shown in  FIG. 3A  according to a specific example embodiment of the disclosure; 
         FIG. 3D  illustrates a front view of the device for ambulation of a subject shown in  FIG. 3A  according to a specific example embodiment of the disclosure; 
         FIG. 4  illustrates a profile view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 5A  illustrates a front view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 5B  illustrates a generally isometric view of a cuff according to a specific example embodiment of the disclosure; 
         FIG. 6A  illustrates a generally isometric view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 6B  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 6C  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 6D  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 6E  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 6F  illustrates a right profile view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 6G  illustrates a left profile view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 6H  illustrates a rear view of the device for ambulation of a subject shown in  FIG. 6A  according to a specific example embodiment of the disclosure; 
         FIG. 7A  illustrates a generally isometric view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 7B  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 7C  illustrates a left profile view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 7D  illustrates a left profile view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 7E  illustrates a left profile view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 7F  illustrates an exploded view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 7G  illustrates an exploded view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 7H  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 7A  according to a specific example embodiment of the disclosure; 
         FIG. 8A  illustrates a generally side view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 8B  illustrates a generally isometric view of the device for ambulation of a subject shown in  FIG. 8A  according to a specific example embodiment of the disclosure. 
         FIG. 9A  illustrates an upper perspective view of a device for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 9B  illustrates a lower perspective view of the device for ambulation of a subject shown in  FIG. 8A  according to a specific example embodiment of the disclosure; and 
         FIG. 9C  illustrates an exploded perspective view of the device for ambulation of a subject shown in  FIG. 8A  according to a specific example embodiment of the disclosure. 
         FIG. 10A  illustrates a generally side view of a device comprising a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 10B  illustrates a generally front view of a device comprising a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 10C  illustrates a generally back view of a device comprising a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 10D  illustrates a side view of a device comprising a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 11A  illustrates a side view of a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 11B  illustrates an external front view of a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 11C  illustrates an internal view of a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 11D  illustrates another internal view of a lift mechanism for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 12A  illustrates a generally back view of a device comprising a lift mechanism with a handle for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure; 
         FIG. 12B  illustrates another generally back view of a device comprising a lift mechanism with a handle for ambulation of a subject having an impaired lower extremity according to a specific example embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure relates, according to some embodiments, to methods, devices, and systems for facilitating ambulation (e.g., walking, running, dancing, and the like) of a subject, optionally, a subject having an impaired lower extremity. For example, a system for facilitating ambulation of a subject may include a walking brace configured to suspend a subject&#39;s lower extremity (e.g., foot) in a non-weight-bearing position. In some embodiments, a system may transfer the subject&#39;s weight to at least a portion of the subject&#39;s lower leg and/or to at least a portion of the subject&#39;s upper leg. A weight-bearing portion of the lower leg may have a vertical span from about the gastrocnemius/solius muscles to about the tibial plateau. A weight-bearing portion of the upper leg may have a vertical span from just superior to the patella to about the proximal one third of the quadriceps femoris. A lower cuff may span up to the entire circumference of a subject&#39;s lower leg. An upper cuff may span up to the entire circumference of a subject&#39;s upper leg. When positioned upright, a subject&#39;s foot may dangle loosely. The subject&#39;s impaired lower extremity may have a wound dressing, a cast, a wrap, or other dressings or garments. With respect to a cast (and/or any other rigid and/or semi rigid material), care may be taken to ensure that the cast does not bear any weight since that load may be transmitted to a subject&#39;s foot. For example, a device may be adapted to accommodate a subject wearing a cast that covers the subject&#39;s ankle and extends up to about the mid-calf region (e.g., by shortening the lower cuff by an amount sufficient to ensure that weight is not transferred from the brace to the cast). It may be desirable, in some embodiments, to include a covering and/or sling to protect and support a lower extremity. The choice of covering and/or sling may be influenced by the nature of the impairment and/or the nature of the dressing. 
     For example, it may be desirable to support and/or immobilize a subject&#39;s foot in a position that is generally perpendicular to the axis of the lower leg (e.g., to prevent and/or minimize Achilles tendon contracture). For example, a sling attached (e.g., by a slide, spring or adjustable canvas component to avoid permitting the foot to bear weight) to at least one cuff and/or at least one strut may be used to secure a subject&#39;s foot in this position. In one example, the sling may surround the foot making contact at or in the general region of the arch. In other examples, the sling may surround the foot, making contact at the heel or the ball of the foot. The portion in contact with the foot may be of any useful material including, but not limited to, synthetic fabrics, plastics, foams (e.g., P-Cell foam), and natural products like cotton or wool. For example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, silicone, rubber, and combinations thereof may be used. If the sling is attached to the cuff and/or strut using a canvas component, the canvas length may be adjusted using any means known in the art including buckles, snaps and the like to provide the foot with the desired tension. According to some embodiments, a sling may partially or completely surround a lower extremity (e.g., a foot). A sling, in some embodiments, may be configured like an ordinary sock. A sling may be attached (e.g., removably attached) to a lower extremity brace (e.g., to a cuff, a strutt, platform, and/or elsewhere). According to some embodiments, a platform may be fitted with one or more pads on its upper surface with the pad positioned, for example, under the ball of the foot or over the entire platform. A foot pad, in some embodiments, may be scored or perforated into segments to allow a health care worker or a subject to customize the support as needed. For example, it may be desirable to minimize Achilles tendon contracture in a subject with an open sore (e.g., diabetic foot ulcer) by providing foot support that does not contact the open sore. Segments of the pad may be selectively removed to avoid that contact. A pad and/or a sling may comprise, according to some embodiments, one or more liners including, for example, a cushioned liner (e.g., a Spenco® liner), a silicon liner, and/or combinations thereof. A lower extremity brace for a subject having or at risk of having a diabetic foot ulcer, for example, may include a sling with a Spenco® liner and an additional, internal, silicon liner. 
     According to some embodiments, an impairment of a lower extremity may include a foot impairment, an ankle impairment, and/or a knee impairment. An impairment may affect a subject&#39;s ability to bear weight on or near the effected region. According to some embodiments, an impairment of a lower extremity may include any condition that makes it undesirable for a subject to bear weight on the extremity. For example, an impairment may exist where the pathology itself impedes the weight bearing capacity. An impairment may also exist where therapy, convalescence, and/or rehabilitation include relieving the region of weight-bearing forces. Examples of lower extremity impairments may include, without limitation, a fractured bone, a broken bone, a sprain, an ulcer (e.g., a diabetic ulcer), an amputation, a suture (e.g., on a distal end of an extremity such as the bottom of a foot or the terminus of a residual limb after an amputation), arthritis, a joint dislocation, a joint subluxation, a torn ligament (e.g., a torn anterior cruciate ligament), a torn cartilage (e.g., a torn meniscus), bursitis, tendonitis, an infection, gout, gangrene, plantar fasciitis, metabolic diseases, bone or cartilage diseases, neuropathic states and/or post-operative states. With regard to amputation, a lower extremity brace may be used, according to some embodiments, as an intermediate step device prior to a permanent below the knee prosthesis, such as waiting for the maturing of the residual limb. In some embodiments, a lower extremity brace may be used as a permanent, below-the-knee prosthesis, for example, those with a very low amputation. A lower extremity brace may be used as a temporary prosthesis for those with residual limb wounds, or those with residual limb breakdown in some embodiments. A lower extremity brace may be used as a post operative protector with a thigh component spanning above the knee to reduce contracture while the brace increases compression to reduce swelling and improve healing. A thigh segment may be removed or articulated below the knee joint to allow for early ambulation of the amputee while the open distal end of the brace will provide relief for the suture site. 
     In some embodiments, increased ambulation may reduce, eliminate, and/or prevent one or more conditions, including, for example, deep venous thrombosis, atrophy, pain (e.g., lower back pain due to bed rest), and/or osteoporosis or other bone loss. Increasing a subject&#39;s ambulation without crutches may decrease the incidence of injuries associated with falling and/or upper body strain. 
     A load redistribution system, in some embodiments, may include a platform, at least one vertical strut fixed to the platform, and at least one cuff fixed to the at least one vertical strut. In some embodiments, one or more fasteners may be used to secure a load redistribution system to a subject&#39;s leg including, for example, belts, buckles (e.g., ski boot buckles, ratcheting buckles), buttons, cams, carabineers, chains, cinches, clasps, D-rings, draw-strings, hooks, levers, locks, loops, slides, snaps, straps, and/or tensioners. These fasteners may be attached to the at least one vertical strut and/or the at least one cuff. In some embodiments, alignment or guide pins may be used in the at least one cuff to guide cuff components into proper alignment with each other and to provide further support for the device when it is surrounding the circumference of at least a portion of the subject&#39;s leg. For example, a system comprising two cuffs configured to contact each other along at least one edge, may include one or more guide pins (e.g., positioned generally perpendicular to the at least one edge) on one cuff and corresponding guide apertures (e.g., sleeves) on the other cuff. In some embodiments, a guide pin may slide releasably in a corresponding guide aperture. A system may include any desired or required number of guide pins and corresponding guide apertures (e.g., from about 1 pair to about 20 pairs). According to some embodiments, all guide pins may be arranged on one cuff and all guide apertures may be located on a facing cuff. In some embodiments, a mixture of guide pins and apertures may be arranged on one cuff with the corresponding guide apertures and guide pins arranged on the other cuff. One or more guide pins and corresponding guide apertures may be included in a system having a single cuff (e.g., a hinged cuff or clam-shell cuff). 
     According to some embodiments, a load redistribution system may be configured to bear and/or redistribute a load (e.g., a subject&#39;s weight). For example, a load redistribution system may be configured to transfer the load of s subject&#39;s weight away from the subject&#39;s foot and transfer it to the subject&#39;s lower and/or upper leg. A load redistribution system may comprise one or more struts positioned adjacent to a subject&#39;s leg (e.g., in front of, behind, to the right, of and/or to the left of a subject&#39;s leg). For example, a single strut may be positioned on the left side of a left leg, on the right side of a right leg, or behind a left leg or right leg. In some embodiments, a strut may be positioned on the generally opposite side of a leg from a subject&#39;s sagittal plane or on the generally opposite side of a leg from a subject&#39;s coronal plane. In some embodiments, a strut positioned generally behind the subject&#39;s leg on which the system is worn may have an S-curve profile. For example, a strut may be configured to have a profile that resembles a letter “S” in that it has two opposing inflection points (e.g., one anterior and one posterior). An S-curve profile may permit clearance for a subject&#39;s foot and/or a normal stride. 
     A strut may comprise, according to some embodiments, two pieces (e.g., an upper piece and a lower piece) joined by a hinge. In some embodiments, a hinge may be configured to permit a limited range (e.g., limited flexion and/or extension) and/or an unlimited range of rotational motion. According to some embodiments, a two-strut system may have a strut on each side of a subject&#39;s leg, with each strut having a single piece (e.g., lower leg only) or two pieces connected by a hinge (e.g., a full leg brace). 
     According to some embodiments, a load redistribution system may be configured to bear a load. A load may include, for example, a subject&#39;s weight, a portion of a subject&#39;s weight, and/or a multiple of a subject&#39;s weight (e.g., 1.1×, 1.2×, 1.5×, and/or 2×). It may be desirable for a load redistribution system to bear a more than a subject&#39;s weight, for example, where the subject may carry additional weight (e.g., a backpack, a bag of groceries, a child, and/or the like) and/or may put the system under additional stress (e.g., through sport, exercise, or the like). In some embodiments, a subject&#39;s lower extremity (e.g., foot) with a load redistribution system in place bears little or no weight, even though weight is born by that leg (e.g., while standing, exercising, working, and/or engaging in other activities). 
     A load redistribution system may include at least one cuff fixed to at least one strut in some embodiments. For example, a system may include a lower leg cuff and an upper leg cuff. A system may include a plurality of lower cuffs and/or a plurality of upper cuffs in some embodiments. For example, if a single cuff would contact and/or cover an injured portion of a lower leg, it may be desirable to instead use two or more lower cuffs configured to minimize and/or avoid contacting/covering the affected region. A cuff may be fixedly or adjustably mounted to a corresponding strut in some embodiments. For example, a strut may include a series of holes (e.g., equidistantly spaced) configured to receive a corresponding pin (e.g., spring-loaded) and/or screw attached to a cuff. A user may slide the cuff along the length of a strut and engage the screw and/or pin when a desired position is found. In some embodiments, a load redistribution system may include continuously variable adjustment system. A cuff may slide along the length of a strut with one or more set screws configured to fix the relative positions of each once a desirable position is found. 
     In some embodiments, a cuff may include a pad disposed to contact at least a portion of a subject&#39;s leg and an outer shell. An inner pad may comprise any desirable gel, foam (e.g., P-Cell foam), and/or other cushioning material(s). A custom fit cuff may facilitate, according to some embodiments, uniform distribution (e.g., uniform, substantially uniform, relatively uniform) of a subject&#39;s weight over the surface area of the cuff. An outer shell may comprise a moldable material. 
     In some embodiments, a cuff may be opened on at least one side to facilitate donning and/or removing the cuff (and attached load redistribution system). For example, a cuff may comprise two outer shells with one or more hinges arranged on one side to allow the cuff to open clamshell-style. Two or more outer shells may fit together without a hinge or other permanent connection according to some embodiments. Once donned, a cuff may be closed and/or secured using any type of fixed or adjustable tensioning system. For example, one or more collars, straps, cinches, guides, loops, hooks, hoops, buckles, and/or combinations thereof may be used. In some embodiments, a tensioning system may include hooks and/or loops (e.g., VELCRO®). 
     According to some embodiments, a load redistribution system, when donned, will increase a subject&#39;s inseam. This may result in an undesirable difference between the inseam of the leg on which a load redistribution system is worn and the inseam of the free leg. Any difference may be offset, at least partially, by wearing a lift (e.g., integrated and/or inserted in a shoe) or other apparatus on the free leg. 
       FIGS. 1A-1D  illustrate an example of a load redistribution system  101  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 1A-1D , load redistribution system  101  may include outsole  104 , platform  106 , lower strut  108 , lower cuff  110 , hinge  136 , upper strut  138 , and upper cuff  140 . 
     Outsole  104  may comprise a foot pad, the bottom of which may be rounded (e.g., rocker outsole) to facilitate walking. The bottom may be ridged as pictured or may have another tread pattern to aid ambulation. Outsole  104  may comprise a hard rubber or other suitable material. Outsole  104  may be generally rectangular in shape as depicted. Other regular and/or irregular shapes may be suitable and/or desirable in some embodiments. Platform  106  may be contiguous with lower strut  108  as shown or may be a separate piece fixedly attached (e.g., welded, bolted) to lower strut  108 . In some embodiments, outsole  104  and platform  106  may be adjustable (e.g., fore and aft) relative to each other. The lower surface of platform  106  may be affixed to outsole  104  with any type of fastener and/or adhesive. Platform  106  may sit atop outsole  104  as shown. In some embodiments, platform  106  may be recessed within outsole  104 , for example, so that the upper surface of outsole  104  is flush with the upper surface of platform  106 . Platform  106  may have any regular or irregular shape. Platform  106  may be somewhat smaller than outsole  104  as depicted or may be sized to match the size of outsole  104 . In some embodiments, it may be desirable for platform  106  to be larger than outsole  104 . Platform  106  may comprise a rigid material suitable for bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     Lower strut  108  may extend vertically from platform  106  to hinge  136 . Upper strut  138  may extend vertically from hinge  136  to a position corresponding to or just below a subject&#39;s hip. Lower strut  108  may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg (e.g., lower leg). Upper strut  138  may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg (e.g., upper leg). Lower strut  108  and/or upper strut  138  may comprise one or more rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     As depicted, lower cuff  110  may comprise anterior pad  112 , anterior pad shell  114 , posterior pad  116 , posterior pad shell  118 , calf collar  120 , and tension adjustment fastener  126 . Pads  112  and/or  116  may independently comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. Pad shells  114  and/or  118  may independently comprise a moldable plastic. In some embodiments, pad shells  114  and/or  118  may independently comprise steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. Pad shells  114  and/or  118  comprising a moldable material may be custom fit to a subject. A moldable plastic may include, for example, a thermoplastic (e.g., capable of more than one cycle of melting, molding, and setting) and/or a thermosetting plastic (e.g., capable of one cycle of melting, molding, and setting). Pads  112  and/or  116  may be adhered, welded, bonded, stitched, or otherwise fixed to pad shells  114  and/or  118 , respectively. 
     Pad shells  114  and/or  118  may be fixedly attached to calf collar  120 . Calf collar  120  may extend up to all the way around the circumference of a subject&#39;s lower leg. Calf collar  120  may include sleeve  122  positioned, for example, at or near its midpoint. Sleeve  122  may be configured to receive strut  108 . Sleeve  122  may have a cavity, the longitudinal axis of which is about perpendicular to the lengthwise axis of strut  108 . Sleeve  122  may be configured to allow collar  120  to slide along the length of strut  108 . Sleeve  122  may include set screw  124  positioned to adjustably contact strut  108 . Each calf collar may be configured to include a sleeve and each sleeve may include a set screw. In use, set screw  124  may be loosened to permit collar  120  to slide along the length of strut  108 . Once a desirable position is found, set screw  124  may be tightened to fix the position of collar  120  on strut  108 . Set screw  124  may be positioned on the inside of collar  120  and directed outwardly toward strut  108  as shown. In some embodiments, set screw  124  may be positioned on the outside of collar  120  and directed inwardly toward strut  108 . As depicted, lower cuff  110  may include three calf collars  120 . In some embodiments, more or fewer collars may be desired and/or required. 
     Tension adjustment fastener  126  may include strap  128 , cinch  130 , and anchor  132 . Strap  128  maybe fixed to one end of calf collar  120  via anchor  132 . Cinch  130  may be fixed to the other end of collar  120 . Cinch  130  may be configured to receive and releasably grip strap  128 . In use, strap  128  may be threaded through cinch  130  and pulled tight to apply a desired amount of pressure on the subject&#39;s lower leg. Cinch  130  may then be closed to fix strap  128  in its position. As depicted, the loose end of strap  120  may be tucked into anchor  132 . 
     Hinge  136  may link lower strut  108  and upper strut  138  and permit rotation of lower strut  108  and upper strut  138  relative to each other. When system  101  is in position on a subject&#39;s leg, the hinge axis of hinge  136  may be parallel or substantially parallel to the hinge axis of the subject&#39;s knee in good health. It may be desirable, in some embodiments, to configure hinge  136  to have a limited and/or selectable degree of rotation (e.g., flexion and/or extension). 
     As depicted, upper cuff  140  may comprise anterior pad  142 , anterior pad shell  144 , posterior pad  146 , posterior pad shell  148 , thigh collar  150 , and tension adjustment fastener  156 . Pads  142  and/or  146  may independently comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. 
     In some embodiments, pad shells  144  and/or  148  may independently comprise a moldable plastic, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. Pad shells  144  and/or  148  comprising a moldable material may be custom fit to a subject. A moldable plastic may include, for example, a thermoplastic (e.g., capable of more than one cycle of melting, molding, and setting) and/or a thermosetting plastic (e.g., capable of one cycle of melting, molding, and setting). Pads  142  and/or  146  may be adhered, welded, bonded, stitched, or otherwise fixed to pad shells  144  and/or  148 , respectively. 
     Pad shells  144  and/or  148  may be fixedly attached to thigh collar  150 . Thigh collar  150  may extend up to all the way around the circumference of a subject&#39;s upper leg. Thigh collar  150  may include sleeve  152  positioned, for example, at or near its midpoint. Sleeve  152  may be configured to receive strut  138 . Sleeve  152  may have a cavity, the longitudinal axis of which is about perpendicular to the lengthwise axis of strut  138 . Sleeve  152  may be configured to allow collar  150  to slide along the length of strut  138 . Sleeve  152  may include set screw  154  positioned to adjustably contact strut  138 . In use, set screw  154  may be loosened to permit collar  150  to slide along the length of strut  138 . Once a desirable position is found, set screw  154  may be tightened to fix the position of collar  150  on strut  138 . Set screw  154  may be positioned on the inside of collar  150  and directed outwardly toward strut  138  as shown. In some embodiments, set screw  154  may be positioned on the outside of collar  150  and directed inwardly toward strut  138 . As depicted, upper cuff  140  may include three thigh collars  150 . In some embodiments, more or fewer collars may be desired and/or required. 
     Tension adjustment fastener  156  may include strap  158 , cinch  160 , and anchor  162 . Strap  158  maybe fixed to one end of thigh collar  150  via anchor  162 . Cinch  160  may be fixed to the other end of collar  150 . Cinch  160  may be configured to receive and releasably grip strap  158 . In use, strap  158  may be threaded through cinch  160  and pulled tight to apply a desired amount of pressure on the subject&#39;s upper leg. Cinch  160  may then be closed to fix strap  158  in its position. As depicted, the loose end of strap  150  may be tucked into anchor  162 . 
       FIGS. 2A-2B  illustrate an example load redistribution system  201  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 2A-2B , system  201  may be configured (e.g., formed and/or adjusted) to include gap  275  between a subject&#39;s foot  272  and the higher of outsole  204  and platform  206 . Gap  275  relieves subject&#39;s foot  272  and/or other lower extremities from bearing weight by diverting the load elsewhere. In some embodiments, gap  275  may be any suitable distance that avoids (e.g., minimizes, eliminates) loading foot  272  and/or other lower extremities. Gap  275  may depend, in part, upon the size and weight of the subject user. For example, a subject with a long foot may be inclined and/or compelled to support some weight on foot  272  at some points in a walking cycle (e.g., when foot  272  is at it&#39;s most rearward position). It may be desirable in such situations to adjust gap  275  to be larger. A subject, for example, a smaller subject, may desire and/or require a smaller gap  675 , for example, to reduce or minimize the difference in length between the effected leg with system  602  and a healthy leg. In some embodiments, gap  275  may be from about 1 cm to about 5 cm, from about 1 cm to about 15 cm, from about 1 cm to about 10 cm, from about 1 cm to about 20 cm, from about 2 cm to about 5 cm, from about 2 cm to about 10 cm, from about 2 cm to about 15 cm, and/or from about 2 cm to about 20 cm. Gap  275  may be less than about 1 cm or more than 20 cm in some embodiments. 
       FIGS. 3A-3D  illustrate an example of a load redistribution system  302  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 3A-3D , load redistribution system  302  may include outsole  304 , platform  306 , lower strut  308 , and lower cuff  310 . 
     Outsole  304  may comprise a foot pad, the bottom of which may be rounded (e.g., rocker outsole) to facilitate walking. The bottom may be ridged as pictured or may have another tread pattern to aid ambulation. Outsole  304  may comprise a hard rubber or other suitable material. Outsole  304  may be generally rectangular in shape as depicted. Other regular and/or irregular shapes may be suitable and/or desirable in some embodiments. Platform  306  may be contiguous with strut  308  as shown or may be a separate piece fixedly attached to strut  308 . The lower surface of platform  306  may be affixed to outsole  304  with any type of fastener and/or adhesive. Platform  306  may sit atop outsole  304  as shown. In some embodiments, platform  306  may be recessed within outsole  304 , for example, so that the upper surface of outsole  304  is flush with the upper surface of platform  306 . Platform  306  may have any regular or irregular shape. Platform  306  may be somewhat smaller than outsole  304  as depicted or may be sized to match the size of outsole  304 . In some embodiments, it may be desirable for platform  306  to be larger than outsole  304 . Platform  306  may comprise a rigid material suitable for bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     Strut  308  may extend vertically from platform  306  to hinge to a position corresponding to or just below a subject&#39;s tibia. Strut  308  may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg (e.g., lower leg). Strut  308  may comprise one or more rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     As depicted, lower cuff  310  may comprise anterior pad  312 , anterior pad shell  314 , posterior pad  316 , posterior pad shell  318 , calf collar  320 , and tension adjustment fastener  326 . Pads  312  and/or  316  may independently comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. In some embodiments, pad shells  314  and/or  318  may independently comprise a moldable plastic, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. Pad shells  314  and/or  318  comprising a moldable material may be custom fit to a subject. A moldable plastic may include, for example, a thermoplastic (e.g., capable of more than one cycle of melting, molding, and setting) and/or a thermosetting plastic (e.g., capable of one cycle of melting, molding, and setting). Pads  312  and/or  316  may be adhered, welded, bonded, stitched, or otherwise fixed to pad shells  314  and/or  318 , respectively. 
     Pad shells  314  and/or  318  may be fixedly attached to calf collar  320 . Calf collar  320  may extend up to all the way around the circumference of a subject&#39;s lower leg. Calf collar  320  may include sleeve  322  positioned, for example, at or near its midpoint. Sleeve  322  may be configured to receive strut  308 . Sleeve  322  may have a cavity, the longitudinal axis of which is about perpendicular to the lengthwise axis of strut  308 . Sleeve  322  may be configured to allow collar  320  to slide along the length of strut  308 . Sleeve  322  may include set screw  324  positioned to adjustably contact strut  308 . Each calf collar may be configured to include a sleeve and each sleeve may include a set screw. In use, set screw  324  may be loosened to permit collar  320  to slide along the length of strut  308 . Once a desirable position is found, set screw  324  may be tightened to fix the position of collar  320  on strut  308 . Set screw  324  may be positioned on the inside of collar  320  and directed outwardly toward strut  308  as shown. In some embodiments, set screw  324  may be positioned on the outside of collar  320  and directed inwardly toward strut  308 . As depicted, lower cuff  310  may include three calf collars  320 . In some embodiments, more or fewer collars may be desired and/or required. 
     Tension adjustment fastener  326  may include strap  328 , cinch  330 , and anchor  332 . Strap  328  maybe fixed to one end of calf collar  320  via anchor  332 . Cinch  330  may be fixed to the other end of collar  320 . Cinch  330  may be configured to receive and releasably grip strap  328 . In use, strap  328  may be threaded through cinch  330  and pulled tight to apply a desired amount of pressure on the subject&#39;s lower leg. Cinch  330  may then be closed to fix strap  328  in its position. As depicted, the loose end of strap  320  may be tucked into anchor  332 . 
       FIG. 4  illustrates an example of a load redistribution system  403  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 4 , load redistribution system  403  may include lower cuff  410 , upper cuff  440 , and rod assembly  480 . 
     Lower cuff  410 , as shown, may include anterior pad  412 , anterior pad shell  414 , calf collar  420 , and tension adjustment fastener  426 . Lower cuff  410  may be secured on a subject&#39;s lower leg in a manner similar to cuffs  110  and  310 . Upper cuff  440 , as shown, may include, posterior pad  446 , posterior pad shell  448 , calf collar  450 , and tension adjustment fastener  456 . Upper cuff  440  may be secured on a subject&#39;s upper leg in a manner similar to cuffs  140  and  340 . Rod assembly  480 , as shown, may include foot  482 , vertical rod  484 , and lateral bar  486 . 
     Lateral bar  486  may be fixed to lower cuff  410  at one end and fixed to vertical rod  484  at the other as shown. In some embodiments, a lower cuff may be fixed directly to a vertical rod allowing the lateral bar to be omitted. Upper cuff  440  may be fixed directly to vertical rod  484 . In some embodiments, a lateral bar may be interposed between an upper cuff and a vertical rod. Rod assembly  480  may comprise one or more rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, fiberglass and combinations thereof. 
     Variations in the weight of a subject, the positioning of the cuff(s), and/or the dimensions of the cuff(s) may influence the pressure on a subject&#39;s leg. In some embodiments, the pressure applied by a cuff on a subject&#39;s leg may be up to about 5 psi, up to about 7.5 psi, up to about 10 psi, up to about 15 psi, up to about 20 psi, up to about 25 psi, and/or up to about 30 psi. In some embodiments, a system may include one or more sensors (e.g., pressure sensors). One or more sensors configured to detect the pressure at a particular location and/or the load born and/or or shifted 
       FIGS. 5A and 5B  illustrate an example of a load redistribution system  501  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 5A , load redistribution system  501  may support a subject&#39;s weight through lower strut  508  (not expressly shown), lower cuff  510  (comprising circumferential pad  511 ), upper strut  538  (not expressly shown), and upper cuff  540  (comprising circumferential pad  541 ).  FIG. 5A  illustrates a method for calculating the pressure to be applied to a subject&#39;s leg as system  501  bears a subject&#39;s weight. Subject&#39;s weight is represented as vector V. As depicted, pads  511  and  541  are positioned at an angle θ relative to vector V. The force applied to pad  511  is represented as vector F P1  and the force applied to pad  511  is represented as vector F P2 . The horizontal component of vector F P1  is represented by vector F X1  and the vertical component is represented by vector F Y1 . The horizontal component of vector F P2  is represented by vector F X2  and the vertical component is represented by vector F Y2 . Since system  501  is configured to bear a subject&#39;s full weight (w), 
         w=F   Y1   +F   Y2   (Equation 1)
 
     If the subject&#39;s weight (w) is distributed evenly between pads  511  and  541 , 
         w/ 2 =F   Y1   =F   Y2   (Equation 2)
 
       Thus, since 
       sin(θ)= F   Y1   /F   P1   (Equation 3)
 
     the force F P1  applied to a subject&#39;s leg may be calculated as follows: 
         F   P1   =F   Y1 /sin(θ)  (Equation 4)
 
     The area of cuff  510  is given by Equation 5: 
       Area=[( d   1   +d   2 )/2 ]*L*π   (Equation 5)
 
     Thus, the pressure (P) on a subject&#39;s leg at cuff  510  is given by Equation 4: 
     
       
         
           
             
               
                 
                   P 
                   = 
                   
                     
                       
                         F 
                         
                           Y 
                            
                           
                               
                           
                            
                           1 
                         
                       
                        
                       
                         / 
                       
                        
                       
                         sin 
                          
                         
                           ( 
                           θ 
                           ) 
                         
                       
                     
                     
                       
                         [ 
                         
                           
                             ( 
                             
                               
                                 d 
                                 1 
                               
                               + 
                               
                                 d 
                                 2 
                               
                             
                             ) 
                           
                            
                           
                             / 
                           
                            
                           2 
                         
                         ] 
                       
                       * 
                       L 
                       * 
                       π 
                     
                   
                 
               
               
                 
                   ( 
                   
                     Equation 
                      
                     
                         
                     
                      
                     6 
                   
                   ) 
                 
               
             
           
         
       
     
     Therefore, if pad  511  is positioned at an angle of 7° (θ), d 1  is 5.41 inches, d 2  is 3.5 inches, L is 7 inches, and the subject&#39;s weight is 180 pounds, the pressure (P) is given by 
     
       
         
           
             
               
                 
                   P 
                   = 
                   
                     
                       
                         ( 
                         
                           w 
                            
                           
                             / 
                           
                            
                           2 
                         
                         ) 
                       
                        
                       
                         / 
                       
                        
                       
                         sin 
                          
                         
                           ( 
                           θ 
                           ) 
                         
                       
                     
                     
                       
                         [ 
                         
                           
                             ( 
                             
                               
                                 d 
                                 1 
                               
                               + 
                               
                                 d 
                                 2 
                               
                             
                             ) 
                           
                           / 
                           2 
                         
                         ] 
                       
                       * 
                       L 
                       * 
                       π 
                     
                   
                 
               
               
                 
                   ( 
                   
                     Equation 
                      
                     
                         
                     
                      
                     7 
                   
                   ) 
                 
               
             
             
               
                 
                   
                     P 
                     = 
                     
                       
                         
                           ( 
                           
                             180 
                              
                             
                               / 
                             
                              
                             2 
                           
                           ) 
                         
                          
                         
                           / 
                         
                          
                         
                           sin 
                            
                           
                             ( 
                             7 
                             ) 
                           
                         
                       
                       
                         
                           [ 
                           
                             
                               ( 
                               
                                 5.41 
                                 + 
                                 3.5 
                               
                               ) 
                             
                              
                             
                               / 
                             
                              
                             2 
                           
                           ] 
                         
                         * 
                         7 
                         * 
                         π 
                       
                     
                   
                    
                   
                     
 
                   
                    
                   
                     P 
                     = 
                     
                       7.5 
                        
                       
                           
                       
                        
                       psi 
                     
                   
                 
               
               
                 
                   ( 
                   
                     Equation 
                      
                     
                         
                     
                      
                     8 
                   
                   ) 
                 
               
             
           
         
       
     
       FIGS. 6A-6H  illustrate an example of a load redistribution system  602  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 6A-6H , load redistribution system  602  may include outsole  604 , platform  606 , strut  608 , support  690 , and cuff  610 . 
     Outsole  604  may comprise a foot pad, the bottom of which may be rounded (e.g., rocker outsole) to facilitate walking. The bottom may be ridged as pictured or may have another tread pattern to aid ambulation. Outsole  604  may comprise a hard rubber or other suitable material. Outsole  604  may be generally rectangular in shape as depicted. Other regular and/or irregular shapes may be suitable and/or desirable in some embodiments. Platform  606  may be contiguous with strut  608  as shown or may be a separate piece fixedly attached to strut  608 . In some embodiments, outsole  604  and platform  606  may be adjustable (e.g., fore and aft) relative to each other. The lower surface of platform  606  may be affixed to outsole  604  with any type of fastener and/or adhesive. Platform  606  may sit atop outsole  604  as shown. In some embodiments, platform  606  may be recessed within outsole  604 , for example, so that the upper surface of outsole  604  is flush with the upper surface of platform  606 . Platform  606  may have any regular or irregular shape. Platform  606  may be somewhat smaller than outsole  604  as depicted or may be sized to match the size of outsole  604 . In some embodiments, it may be desirable for platform  606  to be larger than outsole  604 . Platform  606  may comprise a rigid material suitable for bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     System  602  may include strut  608  positioned substantially behind a subject&#39;s leg when the leg is secured in system  602 . At least a portion of strut  608  may be fixedly connected to and/or contiguous with a posterior portion of platform  606 . At least a portion of strut  608  extends from a posterior portion of platform  606  in the same plane as platform  606  or a plane generally parallel to the plane of platform  606  (“horizontal” portion). At least a portion of strut  608  rises above the plane of platform  606  and generally perpendicular to the plane of platform  606  (“vertical” portion). This vertical portion may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg (e.g., lower leg). Strut  608  may include bend  607  interposed between the horizontal and vertical portions of strut  608 . Bend  607  may be configured to bend or curve upward from platform  606  in a manner that permits a subject a normal or generally normal stride (e.g., heel to toe contact with the ground). Strut  608  may comprise one or more rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. While strut  608  may be rigid to support a subject&#39;s weight, some resilience/flexibility may be tolerated and/or desirable in some embodiments. 
     As depicted, cuff  610  may comprise anterior pad  612 , anterior pad shell  614 , posterior pad  616 , posterior pad shell  618 , and tension adjustment fastener  626 . Pad  612  may include one or more apertures  613 . Shell  614  may include one or more apertures  615 . Pad  616  may include one or more apertures  617 . Shell  618  may include one or more apertures  619 . Pad apertures  613  and  617  may be independently aligned (e.g., partially or completely) with shell apertures  615  and  619 , respectively. Pads  612  and/or  616  may independently comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. Pad shells  614  and/or  618  may independently comprise a moldable plastic. In some embodiments, pad shells  614  and/or  618  may independently comprise steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. Pad shells  614  and/or  618  comprising a moldable material may be custom fit to a subject. A moldable plastic may include, for example, a thermoplastic (e.g., capable of more than one cycle of melting, molding, and setting) and/or a thermosetting plastic (e.g., capable of one cycle of melting, molding, and setting). Pads  612  and/or  616  may be adhered, welded, bonded, stitched, or otherwise fixed to pad shells  614  and/or  618 , respectively. 
     As shown in  FIG. 6C , pad shell  618  may be fixedly attached to support  690 . Pad shells  614  and  618  may be attached to each other through one or more hinges  633 . Support  690  may be attached to strut  608 —one or more screws  624  may be secured to support  690  through one or more holes  625  in strut  608 . As shown in  FIG. 6C , a plurality of holes  625  along a vertical axis of strut  608  affords a health care worker and/or a subject the opportunity to adjust the height of cuff  610 . 
     Tension adjustment fastener  626  may include strap  628 , cinch  630 , and anchor  632 . Strap  628  maybe fixed to posterior pad shell  618  via anchor  632 . Cinch  630  may be fixed to posterior pad shell  618  at a point along the circumference of shell  618  and spaced away from anchor  632 . Cinch  630  may be configured to receive and releasably grip strap  628 . In use, strap  628  may be threaded through cinch  630  and pulled tight to apply a desired amount of pressure on the subject&#39;s lower leg. Cinch  630  may then be closed to fix strap  628  in its position. System  602  may include one, two (pictured), three or more tension adjustment fasteners  626 . 
       FIG. 6B  illustrates an example load redistribution system  602  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 6B , system  602  may be configured (e.g., formed and/or adjusted) to include gap  675  between a subject&#39;s foot  672  and the higher of outsole  604  and platform  606 . Gap  675  relieves subject&#39;s foot  672  and/or other lower extremities from bearing weight by diverting at least a portion of the load elsewhere (e.g., all or substantially all of the load). In some embodiments, gap  675  may be any suitable distance that avoids (e.g., minimizes, eliminates) loading foot  672  and/or other lower extremities. The extent of gap  675  may depend, in part, upon the size and weight of the subject user. For example, a subject with a long foot may be inclined and/or compelled to support some weight on foot  672  at some points in a walking cycle (e.g., when foot  672  is at it&#39;s most rearward position with the toes nearest the ground and the heal elevated). It may be desirable in such situations to adjust gap  675  to be larger. A subject, for example, a smaller subject, may desire and/or require a smaller gap  675 , for example, to reduce or minimize the difference in length between the effected leg with system  602  and a healthy leg. In some embodiments, gap  675  may be from about 1 cm to about 5 cm, from about 1 cm to about 15 cm, from about 1 cm to about 10 cm, from about 1 cm to about 20 cm, from about 2 cm to about 5 cm, from about 2 cm to about 10 cm, from about 2 cm to about 15 cm, and/or from about 2 cm to about 20 cm. Gap  675  may be less than about 1 cm or more than 20 cm in some embodiments. 
       FIGS. 7A-7H  illustrate an example of a load redistribution system  702  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 7A-7H , load redistribution system  702  may include outsole  704 , pad  705 , platform  706 , strut  708 , support  791 , and cuff  710 . 
     Outsole  704  may comprise a foot pad, the bottom of which may be rounded (e.g., rocker outsole) to facilitate walking. The bottom may be ridged as pictured or may have another tread pattern to aid ambulation. Outsole  704  may comprise a hard rubber or other suitable material. Outsole  704  may have any regular or irregular shape. For example, outsole  704  may be configured to resemble the tread of a running shoe, a dress shoe, and/or a boot. As depicted, outsole  704  may include a flange that extends from the plane of the walking surface in a generally vertical direction along the back of strut  708 . This flange may facilitate traction and/or a normal or improved stride. Other regular and/or irregular shapes may be suitable and/or desirable in some embodiments. Platform  706  may be contiguous with strut  708  as shown or may be a separate piece fixedly attached to strut  708 . In some embodiments, outsole  704  and platform  706  may be adjustable (e.g., fore and aft) relative to each other. The lower surface of platform  706  may be affixed to outsole  704  with any type of fastener and/or adhesive. Platform  706  may sit atop outsole  704  as shown. In some embodiments, platform  706  may be recessed within outsole  704 , for example, so that the upper surface of outsole  704  is flush with the upper surface of platform  706 . Platform  706  may have any regular or irregular shape. Platform  706  may be somewhat smaller than outsole  704  as depicted or may be sized to match the size of outsole  704 . In some embodiments, it may be desirable for platform  706  to be larger than outsole  704 . Platform  706  may comprise a rigid material suitable for bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     System  702  may include strut  708  positioned substantially behind a subject&#39;s leg when the leg is secured in system  702 . At least a portion of strut  708  may be fixedly connected to and/or contiguous with a posterior portion of platform  706 . Strut  708  may have an S-shaped profile as shown in  FIG. 7C  or it may form and “L” with platform  706  (not expressly illustrated). At least a portion of strut  708  extends from a posterior portion of platform  706  in the same plane as platform  706  or a plane generally parallel to the plane of platform  706  (“horizontal” portion). At least a portion of strut  708  rises above the plane of platform  706  and generally perpendicular to the plane of platform  706  (“vertical” portion). This vertical portion may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg (e.g., lower leg). Strut  708  may include bend  707  interposed between the horizontal and vertical portions of strut  708 . Bend  707  may be configured to bend or curve upward from platform  706  in a manner that permits a subject a normal or generally normal stride (e.g., heel to toe contact with the ground). Strut  708  may comprise one or more rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. While strut  708  may be rigid to support a subject&#39;s weight, some resilience/flexibility may be tolerated and/or desirable in some embodiments. 
     As depicted, cuff  710  may comprise anterior bladder  712 , anterior shell  714 , posterior bladder  716 , posterior shell  718 , and tension adjustment fastener  726 . Bladder  712  may include one or more protrusions  713 . Shell  714  may include one or more apertures  715 . Bladder  716  may include one or more protrusions  717 . Shell  718  may include one or more apertures  719 . Bladder protrusions  713  and  717  may be aligned with shell apertures  715  and  719 , respectively to reduce or prevent, for example, movement of bladders relative to shells. Bladders  712  and/or  716  may independently comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. Each bladder may have an inlet ( 712   a  and/or  716   a ) and an outlet ( 712   b  and/or  716   b ). System  702  may be custom fit to a subject by mounting system  702  on the subject and subsequently injecting a fill material into a bladder inlet ( 712   a  and/or  716   a ). Fill material may be injected in some embodiment until it begins to be released from bladder outlet ( 712   b  and/or  716   b ). In some embodiments, a fill material may be flowable (e.g., a liquid) when it enters a bladder. A fill material may later convert and/or be converted to a resilient, semi-resilient, or non-resilient gel or non-liquid (e.g., solid) material. Examples of fill materials include, for example, foam, spray foam, gel foam, and/or combinations thereof. 
     Shells  714  and/or  718  may independently comprise a moldable plastic. In some embodiments, shells  714  and/or  718  may independently comprise steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. Shells  714  and/or  718  comprising a moldable material may be custom fit to a subject. A moldable plastic may include, for example, a thermoplastic (e.g., capable of more than one cycle of melting, molding, and setting) and/or a thermosetting plastic (e.g., capable of one cycle of melting, molding, and setting). Bladders  712  and/or  716  may be adhered, welded, bonded, stitched, or otherwise fixed to shells  714  and/or  718 , respectively. 
     As shown in  FIG. 7B , shell  718  may be fixedly attached to support  791 . Support  791  may be attached to strut  708 —one or more screws  724  may be secured to support  791  through one or more holes  725  in strut  708 . As shown in  FIG. 7B , a plurality of holes  725  along a vertical axis of strut  708  affords a health care worker and/or a subject the opportunity to adjust the height of cuff  710 . 
     Tension adjustment fastener  726  may include strap  728 , cinch  730 , and anchor  732 . Strap  728  maybe fixed to posterior shell  718  via anchor  732 . Cinch  730  may be fixed to posterior shell  718  at a point along the circumference of shell  718  and spaced away from anchor  732 . Cinch  730  may be configured to receive and releasably grip strap  728 . In use, strap  728  may be threaded through cinch  730  and pulled tight to apply a desired amount of pressure on the subject&#39;s lower leg. Cinch  730  may then be closed to fix strap  728  in its position. System  702  may include one, two (pictured), three or more tension adjustment fasteners  726 . 
       FIGS. 7D and 7E  illustrate an example load redistribution system  702  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 7D , system  702  may include pad  705  positioned to apply just enough pressure to the bottom of a subject&#39;s foot (e.g., the toes and/or the ball of the foot) to hold it generally perpendicular to the long axis of the lower leg (e.g., tibia and/or fibula). As shown in  FIG. 7E , one or more segments of pad  705  may be removed to accommodate the particular desires or needs of a subject with ulcer  773  or other foot injury. Pad  705  may span up to the entire gap  775 . Pad  705  may comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. 
       FIGS. 7F and 7G  illustrate exploded views of an example load redistribution system  702  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 7G , pad shell  718  may include protrusions  733   a  that complement slots  733   b  in pad shell  714 . When pad shells  714  and  718  come together (e.g., around a subject&#39;s leg), protrusions  733   a  fit into corresponding slots  733   b  and may stabilize the pad shell sections relative to each other. 
       FIG. 7H  illustrates an example load redistribution system  702  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 7H , system  702  may include shell  795  configured to shield and/or protect a subject&#39;s foot from incidental contact with other objects. Shell  795  may be secured to strut  708  with straps  796  and snaps  797  as illustrated. Additional straps, snaps, and/or other fasteners may be added to secure shell  795  (e.g., between shell  795  and outsole  704  and/or platform  708 . 
       FIG. 8A  illustrates an example load redistribution system  800  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIG. 8A , system  800  may include a sling  801  configured to secure a subject&#39;s foot in a particular position (e.g., a non-weight bearing position) for any desirable reason (e.g., patient comfort, protection of an injured or diseased portion of the foot). The sling  801  may attach to at least one cuff  802  and/or at least one strut  803  and its height may be adjusted using a buckle  804 . Alignment or guide pins  805  may be included to guide cuff components into proper alignment with each other and to provide further support for the device when it is surrounding the circumference of at least a portion of the subject&#39;s leg. For example, a system comprising two cuffs configured to contact each other along at least one edge  806 , may include one or more guide pins  805  (e.g., positioned generally perpendicular to the at least one edge) on one cuff and corresponding guide apertures  807  (e.g., sleeves) on the other cuff. In some embodiments, a guide pin  805  may slide releasably in a corresponding guide aperture  807 . A system may include any desired or required number of guide pins and corresponding guide apertures (e.g., from about 1 pair to about 20 pairs). According to some embodiments, all guide pins may be arranged on one cuff and all guide apertures may be located on a facing cuff. In some embodiments, a mixture of guide pins and apertures may be arranged on one cuff with the corresponding guide pins and apertures arranged on the other cuff. 
       FIG. 8B  illustrates the example load redistribution system  800  of  FIG. 8A  from a different perspective and also illustrates an example of the foot in the sling  801 . As discussed previously, the sling  801  may be used to support and/or immobilize a subject&#39;s foot in a desired position without permitting the foot to bear weight. For example, the sling may be used to immobilize the foot in a position that prevents and/or minimizes an Achilles tendon contracture. The sling  801  may attach (e.g., by a slide, spring or adjustable canvas component (e.g., a strap) to avoid permitting the foot to bear weight) to at least one cuff  802  and/or at least one strut  803 . In the instance where canvas strap  808  or other similar material is used for attachment, the length of strap  808  may be adjusted using a buckle  804  or any other means known in the art including snaps, clasps and the like. This permits one to adjust the height of the sling and position the foot in the desired configuration with the desired tension. The portion of the sling  801  in contact with the foot may be of any useful material including, but not limited to, synthetic fabrics, plastics, foams, and natural products like cotton or wool. For example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, silicone, rubber, and combinations thereof may be used. Alignment or guide pins  805  may be included to guide cuff components into proper alignment with each other and to provide further support for the device when it is surrounding the circumference of at least a portion of the subject&#39;s leg. For example, a system comprising two cuffs configured to contact each other along at least one edge  806 , may include one or more guide pins  805  (e.g., positioned generally perpendicular to the at least one edge) on one cuff and corresponding guide apertures  807  (e.g., sleeves) on the other cuff. In some embodiments, a guide pin  805  may slide releasably in a corresponding guide aperture  807 . A system, in some embodiments, may include a guide pin/guide aperture system, a sling system, or both a guide pin/guide aperture system and a sling system. 
       FIGS. 9A-9C  illustrate an example of a load redistribution system  902  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 9A-9C , load redistribution system  902  may include outsole  904 , foot boss  905 , platform  906 , strut  908 , support  990 , and cuff  910 . 
     Outsole  904  may comprise a foot pad, the bottom of which may be rounded (e.g., rocker outsole) to facilitate walking. The bottom may be smooth, may have a fine hatch pattern, or may have another tread pattern to aid ambulation. Outsole  904  may comprise a hard rubber or other suitable material. Outsole  904  may have any regular or irregular shape. For example, outsole  904  may be configured to resemble the tread of a running shoe, a dress shoe, and/or a boot. As depicted, outsole  904  may include a flange that extends from the plane of the walking surface in a generally vertical direction along the back of strut  908 . This flange may facilitate traction and/or a normal or improved stride. Other regular and/or irregular shapes may be suitable and/or desirable in some embodiments. Outsole  904  may comprise one or more layers. For example, outsole  904  may comprise a resilient material fixed to the lower side of platform  906  and a thin, puncture-resistant bottom (e.g., floor-contacting) layer. 
     Platform  906  may be contiguous with strut  908  as shown or may be a separate piece fixedly attached to strut  908 . In some embodiments, outsole  904  and platform  906  may be adjustable (e.g., fore and aft) relative to each other. The lower surface of platform  906  may be affixed to outsole  904  with any type of fastener and/or adhesive. Platform  906  may sit atop outsole  904  as shown. In some embodiments, platform  906  may be recessed within outsole  904 , for example, so that the upper surface of outsole  904  is flush with the upper surface of platform  906 . Platform  906  may have any regular or irregular shape. Platform  906  may be somewhat smaller than outsole  904  as depicted or may be sized to match the size of outsole  904 . In some embodiments, it may be desirable for platform  906  to be larger than outsole  904 . Platform  906  may comprise a rigid material suitable for bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     The upper surface of platform  906  may be covered with a hook and loop fastener material, for example, to removeably attach foot boss  905 . Foot boss  905  may comprise foam pad  905   a , outer shell  905   b , strap  905   c , and tongue  905   d . Foot boss  905  may be positioned (repositioned) as desired to control lateral movement of a subject&#39;s foot (e.g., by lining the bottom of outer shell  905   b  with hook and loop fasteners. This may assist with a subject&#39;s balance, gait, and/or rehabilitation. Foot boss  905  may be used without requiring or encouraging a subject to bear weight on the foot (e.g., distal end of the foot). In some embodiments, system  902  may include foot boss  905  positioned to apply just enough pressure to the bottom of a subject&#39;s foot (e.g., the toes and/or the ball of the foot) to hold it generally perpendicular to the long axis of the lower leg (e.g., tibia and/or fibula). Foot boss  905  may comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. 
     System  902  may include strut  908  positioned substantially behind a subject&#39;s leg when the leg is secured in system  902 . At least a portion of strut  908  may be fixedly connected to and/or contiguous with a posterior portion of platform  906 . Strut  908  may have an S-shaped profile as shown in  FIGS. 9A-9C , where the transition from platform  906  into curve  907  and strut  908  is one smooth curve having at least one inflection point, but no angles or elbows. At least a portion of strut  908  extends from a posterior portion of platform  906  in the same plane as platform  906  or a plane generally parallel to the plane of platform  906  (“horizontal” portion). At least a portion of strut  908  rises above the plane of platform  906  and generally perpendicular to the plane of platform  906  (“vertical” portion). This vertical portion may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg (e.g., lower leg). Strut  908  may include bend  907  interposed between the horizontal and vertical portions of strut  908 . Bend  907  may be configured to bend or curve upward from platform  906  in a manner that permits a subject a normal or generally normal stride (e.g., heel to toe contact with the ground). In this context, “toe” refers to the anterior-most portion of outsole  904  and/or platform  906 . Strut  908  may comprise one or more rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, wood, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. While strut  908  may be rigid to support a subject&#39;s weight, some resilience/flexibility may be tolerated and/or desirable in some embodiments. 
     As depicted, cuff  910  may comprise anterior pad  912 , anterior shell  914 , posterior pad  916 , posterior shell  918 , and tension adjustment fastener  926 . Anterior pad  912  and posterior pad  916  may have a generally smooth outer periphery that is bonded to the inner periphery of anterior shell  914  and posterior shell  918 , respectively. Pads  912  and/or  916  may independently comprise flexible, elastomeric, and/or resilient materials including, for example, polyurethane, polyethylene, neoprene, ethylene vinyl acetate, foam (e.g., P-Cell foam), silicone, rubber, and the like. Pads  912  and/or  916  may be dimensioned to leave little or no gaps when system  902  is worn to minimize and/or eliminate potential pinch sites that could compromise comfort. 
     Shells  914  and/or  918  may independently comprise a moldable plastic. In some embodiments, shells  914  and/or  918  may independently comprise steel, a steel alloy, aluminum, an aluminum alloy, titanium, a titanium alloy, carbon fiber, an aramid fiber, a para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. Shells  914  and/or  918  comprising a moldable material may be custom fit to a subject. A moldable plastic may include, for example, a thermoplastic (e.g., capable of more than one cycle of melting, molding, and setting) and/or a thermosetting plastic (e.g., capable of one cycle of melting, molding, and setting). Pads  912  and/or  916  may be adhered, welded, bonded, stitched, or otherwise fixed to shells  914  and/or  918 , respectively. Shells  914  and/or  918  may have an upper edge and a lower edge feature. As shown, the upper edges of shells  914  and/or  918  have a bias generally away from a subject&#39;s leg. Similarly, the lower edges of shells  914  and/or  918  have a bias generally away from a subject&#39;s leg. This feature may reduce chafing and/or bruising. 
     As shown in  FIG. 9B , shell  918  may be fixedly attached to support  990 . Support  990  may be attached to strut  908 —one or more screws  924  may be secured to support  990  through one or more holes  925  in strut  908 . Support  990  may be configured as a an extension of posterior shell  918  as shown or it may form a separate piece. 
     Tension adjustment fastener  926  may include strap  928 , cinch  930 , and anchor  932 . Strap  928  maybe fixed to anterior shell  914  via anchor  932 . Cinch  930  may be fixed to anterior shell  914  at a point along the circumference of shell  918  and spaced away from anchor  932 . Cinch  930  and anchor  932  may be positioned so strap  928  has a posterior bias. As shown in  FIG. 9B , straps  928  extend from anchor  932  around the posterior portion of posterior shell  918  and continue around to cinch  930 . Cinch  930  may be configured to receive and releasably grip strap  928 . In use, strap  928  may be threaded through cinch  930  and pulled tight to apply a desired amount of pressure on the subject&#39;s lower leg. Cinch  930  may then be closed to fix strap  928  in its position. System  902  may include one, two (pictured), three or more tension adjustment fasteners  926 . 
     Anterior shell piece may comprise anterior pad  912 , anterior shell  914 , and tension adjustment fastener  926 . Posterior piece may comprise outsole  904 , platform  906 , curve  907 , strut  908 , pad  916 , shell  918 , and support  990 . A subject may put system  902  on a lower extremity by separating anterior shell piece from posterior piece, contacting posterior piece with a posterior portion of a lower extremity, engaging anterior shell piece with posterior piece including passing straps  928  around a posterior portion of the lower extremity and threading them in cinches  930 . Upon engagement, anterior shell  914  at least partially encircles posterior shell  918  and/or a lateral periphery of anterior pad  912  abuts a lateral periphery of posterior pad  914 . 
     A lower extremity brace may comprise, according to some embodiments, a prosthetic appliance. For example, a lower extremity brace configured to be worn by an amputee, may comprise a portion of the missing appendage. In some embodiments, a lower extremity brace may comprise a strut (e.g., an S-curve strut) having a proximal and a distal end, a cuff attached to the proximal portion of the strut, and a prosthetic appliance (e.g., an artificial foot) attached to the distal end of the strut. In some embodiments, a cuff may be slidably attached to a strut to permit adjustment (e.g., adjustment based on the height of the wearer and/or the length of the residual extremity). An amputee may wear a lower extremity brace in such a way that weight is distributed away from the missing portion of the extremity to a portion of the extremity that remains intact or substantially intact. 
       FIGS. 10A-10D  illustrate an example load redistribution system  1002  for ambulation of a subject having a lower extremity impairment, in accordance with embodiments of the present disclosure. As shown in  FIGS. 10A-10D , the load redistribution system  1002  may include boot  1095 , anterior cuff  1015 , posterior cuff  1014 , material cover  1041 , and lift mechanism  1005 . Load redistribution system  1002 , in some embodiments, may permit custom adjustment of fit to particular subject respective to the subject&#39;s size, anatomy, and/or physical condition (e.g., location and nature of any adverse medical condition). 
     In some embodiments, the boot  1095  may have a lengthwise axis that is approximately parallel to the lengthwise axis of a subject&#39;s leg. The boot  1095  may comprise ultra lite vented polymer, designed for the lower extremity. But the boot  1095  is not limited to comprising the ultra lite vented polymer, and may instead comprise one or more other rigid materials capable of bearing a subject&#39;s weight. Examples of such materials include, without limitation, steel, steel alloy, aluminum, an aluminum alloy, titanium, titanium alloy, carbon fiber, wood, aramid fiber, para-aramid fiber (e.g., KEVLAR), fiberglass, and combinations thereof. 
     In some embodiments, the boot  1095  may comprise one or more boot liners  1040  and a material cover  1041 . The boot liner  1040  may comprise breathable and latex-free foam. In other embodiments, the boot liner  1040  may be a cushioned liner (e.g., a Spenco® liner), a silicon liner, and/or combinations thereof. The material cover  1041  may comprise the same material as the boot liner  1040 . In other embodiments, the material cover  1041  may comprise materials different from the material used for the boot liner  1040 . In some embodiments, the boot liner  1040  and the material cover  1041  may form a single body, while in other embodiments, the boot liner  1040  and the material cover  1041  may not form a single body. 
     In some embodiments, the boot  1095  may comprise one or more density low friction inserts (not shown) between a base  1044  of the boot  1095  and a subject&#39;s foot (not shown). The density low friction inserts may provide sufficient friction between the base  1044  and the subject&#39;s foot to provide sufficient traction and prevent slippage. In some embodiments, the boot  1095  may comprise a reversed Spenco® type interface to improve adherence to the skin for a higher unloading capacity. In other embodiments, the boot  1095  may comprise other interfaces for improving adherence to the skin. In some embodiments, the boot  1095  may comprise an ultra lite sole (not shown) and a rocker non-slip base (not shown) to enable smooth gait transition and stability. 
     In some embodiments, the boot may comprise a suspension mechanism (not shown) and enclosure designed for all lower extremity injuries, including, but not limited to, fractures, sprains, strains, contusions, and lacerations. In some embodiments, the boot  1095  may be provided in various sizes, for example, in Small, Medium, Large, and X-large in order to cater to diverse patients. 
     Boot  1095  may have, in some embodiments, a generally horizontal extent and a generally vertical extent. A horizontal extent may have flanges or wings to at least partially surround a subject&#39;s foot, if present. A horizontal extent may have one or more holes or perforations in each flange or wing independently. A vertical extent may have flanges or wings to at least partially surround a subject&#39;s lower leg, if present. A vertical extent may have one or more holes or perforations in each flange or wing independently. 
     In some embodiments, the boot  1095  may be linked or connected to cuffs  1014  and  1015 . Cuffs  1014  and  1015  may slide vertically in relation to the boot  1095  through the use of the lift mechanism  1005  (explained further below). A nested configuration between cuffs  1014  and  1015  and boot  1095  may stabilize a subject&#39;s leg against lateral sway relative to boot  1095 . For example, posterior cuff  1014  may have a generally convex surface configured and shaped to conform to and longitudinally slide within a concave surface of boot body  1096 , but generally prevent or dampen lateral or rotational movement. Posterior cuff  1014  may have a generally convex surface and a generally vertical extent of a boot body may have a generally concave surface, the convex surface and the concave surfaces sized and contoured to conform to each other and permit posterior cuff  1014  and the vertical extent of boot body  1096  to slide longitudinally relative to each other. Cuffs  1014  and  1015  may be stabilized against sway (e.g., lateral or rotational sway relative to boot  1095 ), in some embodiments, by including in boot  1095  including wings or flanges  1097  that partially surround at least posterior cuff  1014 . Cuffs  1014  and  1015  may comprise the same materials as the boot  1095 . In other embodiments, the cuffs  1014  and  1015  may comprise different materials as the boot  1095 . The cuff  1014  may comprise a plurality of fingers  1045  to improve flexibility and allow the cuff  1014  to better conform to the shape of an extremity. The cuffs  1014  and  1015  may have a plurality of slits or openings  1017 . The cuffs  1014  and  1015  may include a pad  1016 . The pad  1016  may comprise the same material as the boot liner  1040 , but may also comprise any desirable gel, foam (e.g., P-Cell foam), and/or other cushioning material(s). 
     In some embodiments, the anterior cuff  1015  and the posterior cuff  1014  may form a single body, adjoined only on one side so that the anterior cuff  1015  may be adjusted according to a subject&#39;s leg size. But in other embodiments, the anterior cuff  1015  and the posterior cuff  1014  are separate components that are connected by use of multiple fasteners  1026 . The multiple fasteners  1026  may enter the openings  1017  to fasten the cuffs  1014  and  1015  together. Further, the multiple fasteners  1026  ensure maximum shaping and contact with a shape of the lower extremity. 
     In some embodiments, the fasteners  1026  may be tension adjustment fasteners. In some embodiments, the fasteners  1026  comprise straps and a buckle (not shown). The length of a strap may be adjusted using a buckle or any other means known in the art including snaps, clasps and the like. In other embodiments, the fasteners  1026  may include strap (not shown), cinch (not shown), and anchor (not shown). The fasteners  1026  may also come in other form, such as belts, buckles (e.g., ski boot buckles, ratcheting buckles), buttons, cams, carabineers, chains, cinches, clasps, D-rings, draw-strings, hooks, levers, locks, loops, slides, snaps, and/or tensioners. 
     In some embodiments, the load redistribution system  1002  may include a lift mechanism  1005  that allows the cuffs  1014  and  1015  to be able to vertically slide in relation to the boot  1095 . This allows the calf section of a subject&#39;s leg to be raised or lowered, thereby unloading the lower extremity from the base  1044  of the boot  1095 . In some embodiments, the left mechanism  1005  may be an adjustable suspension lift mechanism, which enables loading and unloading of the lower extremity in incremental steps or percentages. In some embodiments, a load redistribution system may have a flexible, bivalve PTB shell design aimed specifically for load redistribution around tibial fractures. As shown, cuffs  1014  and  1015  may be configured to extend beyond (e.g., rise above) boot body  1096 . 
       FIGS. 11A-11D  illustrate an example lift mechanism  1105 , in accordance with embodiments of the present disclosure.  FIG. 11A  illustrates a side view of an example lift mechanism  1105  and  FIG. 11B  illustrate a front view of the example lift mechanism  1105 . In some embodiments, the lift mechanism  1105  comprises handle  1177  and screws  1188 . The screws  1188  enable the lift mechanism  1105  to be attached to the boot  1095 . In an embodiment, there may be four screws  1188  that connect the lift mechanism  1105  to the boot  1095 , but in other embodiments, there may be any number of screws  1188  to connect the lift mechanism  1105  to the boot  1095 . Also, in other embodiments, bolts, adhesives, fasteners, or any other appropriate means may be used to connect the lift mechanism  1105  to the boot  1095 . In some embodiments, the lift mechanism  1105  may comprise the same material as the boot  1095 , but in other embodiments, the lift mechanism  1105  may comprise any material that is durable enough to lift the cuffs  1014  and  1015  in relation to the boot  1095 . 
     Handle  1177  can be rotated or cranked such that cuffs  1014  and  1015  slide vertically in relation to boot  1095  through the use of lift mechanism  1005 . As illustrated in  FIGS. 11C-11D , cranking handle will rotate wheel  1178 , which in turn rotates wheel  1179 . In some embodiments, wheels  1178  and  1179  comprise a worm screw and a worm gear, respectively, such that rotating worm screw  1178  with handle  1177  drives worm gear  1179  to turn. In some embodiments, worm gear  1179  is connected to cuffs  1014  and  1015  such that rotating or turning worm gear  1179  causes cuffs  1014  and  1015  to slide vertically in relation to boot  1095 . In an embodiment, turning the handle in a clockwise direction raises cuffs  1014  and  1015  relatively to boot  1095  and turning handle  1177  in a counter-clockwise direction lowers cuffs  1014  and  1015  relatively to boot  1095 . In another embodiment, turning handle  1177  in a clockwise direction lowers cuffs  1014  and  1015  relatively to boot  1095  and turning handle  1177  in a counter-clockwise direction raises cuffs  1014  and  1015  relatively to boot  1095 . In some embodiments, by vertically sliding cuffs  1014  and  1015  in relation to boot  1095 , cuffs  1014  and  1015  are mounted at a position sufficient to suspend the at least a portion of the impaired lower extremity in a non-weight-bearing position, wherein boot  1095  and at least one of cuffs are configured to (a) bear at least the subject&#39;s full weight and (b) distribute the weight born to at least a portion of the subject&#39;s leg other than the subject&#39;s foot. 
     In some embodiments, a lift mechanism may comprise a first wheel, a second wheel engaged with the larger wheel, and a handle rotatably linked to the second wheel, wherein the second wheel is larger than the first wheel. For example, in  FIG. 11D , wheel  1178  (i.e., worm screw  1178 ) is smaller than wheel  1179  (i.e., worm gear  1179 ), but in other embodiments wheel  1178  may be larger than wheel  1179 . Thus, in some embodiments, the first wheel and the second wheel may be configured as a worm screw and worm gear respectively. According to some embodiments, a load redistribution system may comprises a shaft fixed to the posterior cuff and engaged to a worm screw such that rotation of the worm screw relative to the shaft vertically translates the posterior cuff. Thus, a method for redistributing a subject&#39;s weight may comprise adjusting the position of at least the posterior cuff relative to the boot body by rotating the handle, which in turn moves the worm gear relative to the worm screw, which laterally translates at least the posterior cuff. 
     In embodiments illustrated in  FIGS. 11A-11D , handle  1177  has a ball point tip that may be used by a user to turn handle  1177 . But in other embodiments, as illustrated in  FIGS. 12A-12B , handle  1277  may have a knob  1276  to facilitate the turning. The handle may come in many shapes and forms as long as they enable wheels  1178  and  1179  to rotate together for lift mechanism  1005  to function. 
     As will be understood by those skilled in the art who have the benefit of the instant disclosure, other equivalent or alternative compositions, devices, methods, and systems for redistributing a load can be envisioned without departing from the description contained herein. Accordingly, the manner of carrying out the disclosure as shown and described is to be construed as illustrative only. 
     Persons skilled in the art may make various changes in the shape, size, number, and/or arrangement of parts without departing from the scope of the instant disclosure. For example, the position and number of struts, pads, collars, and/or cuffs may be varied. In some embodiments, pads, pad shells, collars, and/or cuffs may be interchangeable. Interchangeability may allow the pressure exerted on a lateral surface of a subject&#39;s leg to be custom adjusted (e.g., by substituting larger or smaller pads). In addition, the size of a device and/or system may be scaled up (e.g., to be used for adult subjects) or down (e.g., to be used for juvenile subjects) to suit the needs and/or desires of a practitioner. Also, where ranges have been provided, the disclosed endpoints may be treated as exact and/or approximations as desired or demanded by the particular embodiment. In addition, it may be desirable in some embodiments to mix and match range endpoints. All or a portion of a device and/or system for redistributing a load may be configured and arranged to be disposable, serviceable, interchangeable, and/or replaceable. These equivalents and alternatives along with obvious changes and modifications are intended to be included within the scope of the present disclosure. Accordingly, the foregoing disclosure is intended to be illustrative, but not limiting, of the scope of the disclosure as illustrated by the following claims.