Abstract:
A cloth covered, thermally insulated therapeutic boot. Hook and loop fasteners and straps are arrayed about the boot to control the support angle between the foot and calf. Numerous other hook and loop fasteners are fitted to the boot surfaces to secure panels that wrap to define the boot. A contour shaped and vented foam calf support is secured to the boot to support the calf and elevate the heel within the boot, when the boot is supported. Hinge pieces mount between the calf support and a rigid heel cradle. Hook and loop fasteners secure the hinge straps to the calf support. Compressible, flanged hinge pins mount to the hinge straps to permit rotations relative to stops.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to therapeutic footwear and, in particular, to an insulated, fleece-lined, cloth boot having a hinged heelpiece, polyurethane calf support and several hook and loop fastened straps and wrappings that retain the calf support to the boot and the boot to the foot. 
   A variety of leg wear and footwear have been developed for pre and post-operative patient therapy situations. These items are worn to prevent vasoconstriction and promote vasodilation to maintain blood circulation and thereby prevent clotting. They also physically protect and warm the legs and feet from skin trauma such as ulcerations, cracking and abrasions. By keeping the legs and feet warm, the blood vessels don&#39;t constrict and the blood flow is maintained. 
   Applicant sells fleece-lined footwear of the foregoing type. A fleece-lined, hook and loop fastened boot is shown in U.S. Pat. Des. 326,556. 
   Other manufacturers sell footwear to accommodate the foregoing and other conditions. Such footwear can include features to prevent foot drop. Extraneous braces are also available for use with the footwear to permit walking. 
   The present improved footwear was developed to provide therapeutic footwear that intrinsically prevents foot drop, permits ambulation and significantly off-loads weight from the heel. Weight is particularly shifted from the heel to the posterior surface of the calf via a raised conformal contour. The boot is constructed with a fleece lining to insulate the foot and calf. A semi-rigid, ventilated foam insert having a contoured interior surface supports the calf when lying in a reclined position. The heel is simultaneously elevated and displaced away from contact with the footwear and particularly an adjacent heel cradle. The rigid heel cradle includes a hinged hook and loop strap piece that mates with a fastener attached to the foam support. Numerous other hook and loop fasteners are fitted to the cloth surfaces and attach to straps and cover pieces that wrap to secure the calf support and heel cradle to the boot and configure the boot about the foot. An anti-rotation bar is fastens beneath a heel cover piece to prevent abduction/obduction. 
   SUMMARY OF THE INVENTION 
   It is accordingly a primary object of the invention to provide thermally insulated footwear for pre and post-operative recuperation to stimulate blood circulation. 
   It is a further object of the invention to provide a fleece lined fabric boot with a number of hook and loop fasteners fitted to the boot surfaces, depending straps and cover pieces that collectively wrap and attach together to configure the boot. 
   It is a further object of the invention to provide a fleece lined fabric boot with a ventilated foam insert that supports the calf when lying in a reclined position. 
   It is a further object of the invention to provide a ventilated foam insert having a conformal contoured interior surface that supports the calf and elevates the heel away from a heel cradle (i.e. off-loads weight from the heel), when lying in a reclined position. 
   It is a further object of the invention to provide a fleece lined fabric boot with a rigid heel cradle that includes a hinged hook and loop strap piece that mates with a fastener attached to the foam support. 
   It is a further object of the invention to provide a flexible hinge pin means to detachably secure a hinged hook and loop strap piece to a rigid heel cradle and rotation limiting means to control foot movement during ambulation. 
   The foregoing objects, advantages and distinctions of the invention are obtained in a presently preferred fleece lined, fabric boot of the invention. The boot has several tabs of hook and loop fastener materials arrayed about the boot that mate with associated straps and cover pieces. The straps and cover pieces align to define and control the fitting of the boot. Detachable straps also extend from the upper surfaces of the boot to the toe region to prevent foot drop. 
   A concave polyurethane foam calf support mounts within the boot. Ventilation apertures are formed in the calf support. The longitudinal interior surface of the support presents a raised, contoured surface that conforms to the calf and elevates the heel when weight is shifted onto the back of the calf support. The calf support is contained between the fabric cover and insulated liner. Hook and loop fasteners secured to overlapping flaps of the boot cover are aligned along the posterior longitudinal surface of the cover to secure the support to the boot. 
   A rigid heel cup or cradle includes hinged hook and loop strap pieces that mate with fasteners attached to the foam support. Split, compressible, flanged hinge pins project from the heel cup and cooperate with rotation-limiting slots and captured pins to control movement of the heel cup relative to the calf support. Transverse hook and loop fasteners attached to the heel cup and a fabric cover piece that covers the heel and sole regions contain the heel/sole cover to the heel cup to the boot. The foam support and heel cup can thereby rotate relative to one another to permit ambulation. 
   Still other objects, advantages, distinctions and constructions of the invention will become more apparent from the following description with respect to the appended drawings. Similar components and assemblies are referred to in the various drawings with similar alphanumeric reference characters. The description should not be literally construed in limitation of the invention. Rather, the invention should be interpreted within the broad scope of the further appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective drawing of the boot with the boot strapped closed and an abduction bar shown at  FIG. 5  secured thereto. 
       FIG. 2  is a perspective drawing shown in partial cutaway and showing the boot folded open and exposing a foam calf support and hinged heel cradle. 
       FIG. 3  is a perspective drawing shown in exploded assembly and showing the heel cup or cradle and ambulatory hinge. 
       FIG. 4  is a perspective drawing showing the calf support mounted to the heel cradle. 
       FIG. 5  is a perspective drawing showing an abduction bar that mounts to the boot in the region of the juncture between the calf support and heel cup to prevent rotation of the boot. 
   

   Similar structure throughout the drawings is referred to with the same alphanumeric reference numerals and/or characters. 
   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIGS. 1 and 2 , perspective views are shown to the improved therapeutic boot  2  of the invention. The boot  2  is covered with an air permeable outer fabric cover  4 . The cover  4  is sewn from a durable velour cloth. Other materials such as a heavyweight cotton or cordura, among other fabrics, can also be used. A thermal insulation liner  6  (shown in cutaway), such as THINSULATE, can be sewn or attached to the cover  4  or beneath a separate lining. The interior surface of the boot  2  and/or lining  6  is faced with a fleece lining  8 . The lining  8  provides a soft comfortable surface that contacts the skin. The fleece  8  traps air, yet permits air circulation around the foot and leg to enhance the thermal insulation properties of the boot  2 . 
   The boot  2  opens full-length along its front or anterior surface at right and left front or tongue panels  10  and  12  and right and left foot panels  14  and  16 . The panels  10 - 16  wrap and overlap each other. Strips of hook and loop fasteners  18  and  20  are aligned along the longitudinal edge of the front panel  10  and in spaced, transverse relation along the interior of the front panel  12 . Separate straps  22  and  24  are fitted with strips of hook and loop fastener material  23  and  25  and mount over the foot panels  14  and  16 . When the panels  14  and  16  are overlapped, the straps  22  and  24  bind the foot and toes in the boot  2 . 
   Straps  26  and  28  extend from a portion of a fleece collar  30  of the boot  2  and contain hook and loop tabs  31 . Another set of straps  27  and  29  that contain mating hook and loop tabs  32  extend from the lateral sides of the toe panels  14  and  16 . Upon securing the straps  26 ,  29  and  27 , 28  together, the angle between the foot and calf is fixed. In normal circumstances, the angle is set to prevent over-extension of the foot in either a reclined or walking posture. 
   With additional attention to  FIG. 2 , a heel and sole panel  34  is sewn to the toe panels  14  and  16  in the region of the sole of the boot  2 . The panel  34  is covered with beads of nylon tufting  36  to provide traction, although exterior of the panel  34  could be plain. The tufting  36  or any other traction enhancing material can be applied to the panel  34  in any desired manner or pattern to facilitate traction. The posterior or heel end of the panel  34  includes a transverse strip  38  of hook and loop material that mates with a strip  40  secured to a rigid heel cup or cradle  48 . The boot  2  is thereby able to freely rotate at the heel cup  48  and the panel  34  is free to flex during ambulation. More details to this attachment and the effected possible ambulation are discussed below. 
   The panel  34  also covers an elastic strap or panel  42  that extends between leg panels  44  and  46  that align with the calf. The panel  42  extends across the bottom of the heel cup  48  and over a foam pad  43  that covers the interior and a portion of the bottom surface of the rigid heel cup  48 . The panels  34  and  42  retain the heel cup  48  and a rigid foam, channel piece or calf support  50  to the boot  2 . Overlapping edges of the leg panels  44  and  46  are separately secured together along the posterior surface of the calf support  50  with mating longitudinal strips  47  and  49  of hook and loop fastener material. 
   The calf support  50  is contained in a pocket formed between the cover  4  and lining  8  along the lengths of the leg panels  44  and  46 . The detachable strips  47  and  49  facilitate the mounting of the support  50  to the boot  2 . 
   With additional attention to  FIGS. 3 and 4 , details are shown to the heel cup  48  and calf support  50 . The calf support  50  is molded from polyurethane foam, although a variety of foams and semi-rigid plastics can be used. The foam is selected to exhibit a sufficient durometer to compress and conform to the calf yet support the calf such that the heel only minimally contacts the heel cup  48 . 
   The calf support  50  is formed with an open-ended, longitudinal channel or trough  52  that contains the calf. The wall thickness of the calf support  50  is profiled to be thicker at the posterior surface and taper inward as the walls extend around the calf to the edges adjacent the front panels  10  and  12 . A raised, contoured surface or bump  51  is aligned in the region of the Achilles tendon to assure the heel doesn&#39;t contact the heel cup  48  and/or is supported in non-load bearing relation thereto. A number of vent holes  54  extend through the support  50  along the posterior surface of the support  50  to facilitate airflow when the leg is supported for protracted periods. Strips of hook and loop fastener material  56  are also affixed to the exterior sides of the calf support  50  and mate with tabs  57  at the hinge straps  58  that extend from the heel cup  48 . 
   The heel cup  48  is constructed from a rigid nylon or plastic material and includes a number of vent holes  60 . The cup  48  extends vertically to a region beneath the ankle. The cup  48  provides a rigid interface that shrouds and protects the posterior and bottom surfaces of the heel. The cup  48  is particularly shaped and sized to assure minimal contact with the heel when the leg is supported and limit contact with the heel and ankle during walking to prevent abrasion. 
   The calf support  50  extends into and cushions the sides and rear of the cup  48 , except in the region of a “U-shaped” cutout  59 . The pad  43  cushions the bottom interior of the cup  48 . Collectively, the lower edges of the support  50  and pad  43  comfortably support and protect the heel when the user elects to walk on the boot  2 . 
   Walking is facilitated via the novel manner of attaching the calf support  50  to the heel cup  48 . In particular, the hinge straps  58  that extend from the tabs  57  at the calf support  50  mount to the sides of the heel cup  48  and interlock with flexible hinge pins  62  that align with a keyed, hinge slot  64  in each strap  58 . Flanges or bent locking tabs  65  at the ends of the pins  62  detachably secure the straps  58  to the heel cup  48 . One or both of two adjacent slots  66  and  68  align with a limit or stop member  70  that projects from the cradle  48 . The rotation of each hinge strap  58  is limited by the cooperation of the stop  70  and slots  66  and/or  68 . 
   The hinge straps  58  are molded from a flexible nylon and although relatively rigid, provide a degree of flexion. An outwardly extending, curved or bowed section  72  is formed in the region of the ankle. Upon properly fitting the hinge strap  58  to the calf support  50  and the boot  2  to a user, the heel cup  48  can rotate without contacting the ankle and the fleece lining  8 , support  50  and cushion pad  43  protect the ankle. 
     FIG. 5  depicts an abduction bar  80  that can be mounted to the boot  2  in the region of the juncture between the calf support  50  and heel cup  48 , such as shown in FIG.  1 . The bar  80  includes a horizontal section  82  and vertical risers  84  and  86 . The foot is secured to the bar  80  in the region between the risers  84  and  86 . The bar  80  is secured beneath the panel  34  in the region of the fasteners  38  and  40 . The length of the bar  80  and risers  84  and  86  are sized to prevent rotation and generally restrict movement of the boot  2  and foot. 
   The boot  2  advantageously protects and thermally insulates the foot and lower leg of pre and post-operative users. The cooperation of the calf support  50  and hinged heel cup  48  permits ambulation without the extraneous supports. The heel cup  48  and calf support  50  can also be removed and detached from one another to facilitate cleaning or repair. 
   While the invention has been described with respect to a number of preferred constructions and considered improvements or alternatives thereto, still other constructions may be suggested to those skilled in the art. It is to be appreciated that selected ones of the foregoing features can be used singularly or be arranged in different combinations to provide a variety of improved footwear. The foregoing description should therefore be construed to include all those embodiments within the spirit and scope of the following claims.