Abstract:
An ankle brace for restricting dorsiflexion and promoting plantarflexion of the foot relative to the leg. The ankle brace includes a lower leg assembly worn on the wearer lower leg, a foot assembly worn on the wearer&#39;s foot; and one or more hinge assemblies rotatably connecting the lower leg assembly to the foot assembly. The hinge assembly provides a positive or resistive force on the top foot assembly to prevent dorsiflexion and/or to promote plantarflexion to reduce knee injuries.

Description:
[0001]     This application claims the benefit or Unites States Provisional Patent Application 60/739,331 filed on Nov. 23, 2005, the entirety of which is incorporated herein by reference. 
     
    
       [0002]     This application includes material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office files or records, but otherwise reserves all copyright rights whatsoever.  
       FIELD OF THE INVENTION  
       [0003]     The present invention relates generally to orthopedic braces and, in particular, to ankle braces, foot braces, ankle supports, or foot supports.  
       BACKGROUND OF THE INVENTION  
       [0004]     The human ankle and knee joints involve complex mechanisms providing for extension, flexion, and rotary movement. The bones, cartilage, and ligaments provide a myriad of components within the joints making them susceptible to injury. Known ankle braces are focused on supporting the components within the ankle itself with no thought or design provided to prevent or assist with injuries to other joints including the knee.  
         [0005]     One of the most severe injuries to the knee is an anterior cruciate ligament (“ACL”) rupture. The ACL is also one of the most commonly disrupted ligaments in the knee. It is estimated that each year in the United States there are Epidemiologic studies have documented a significantly higher ACL injury rate in women as compared to male athletes, especially in team sports that require cutting and pivoting such as basketball, football, and soccer. Women suffer two to eight times the number of ACL injuries in basketball and soccer as men.  
         [0006]     Research into ACL injuries, including videotape analysis of athletes who sustained an ACL injury, provided that landing on a flat foot with the knee close to full extension and often in valgus (outward turning of the lower leg in relation to the thigh) predisposes one to an ACL injury. Therefore, ACL injury prevention programs emphasize teaching athletes to land on the balls of their feet with the knees flexed avoiding valgus. Test results of these prevention programs demonstrate a reduction in the incidence of ACL injuries.  
         [0007]     Further, since the leg acts as a kinetic chain with the forces starting at the foot and traveling up to the knee, the ankle is a logical location for an ACL prevention device. If deleterious ground reaction forces are not dissipated at the lower leg, it is unlikely that a knee brace can effectively reduce these forces below the threshold to prevent ACL injury.  
         [0008]     Therefore, what is needed is an ankle brace or support which provides an appropriate amount of resistance to the foot or ankle joint to properly position the foot for landing on the forefoot (balls of their feet) thereby preventing ACL injuries.  
       SUMMARY OF INVENTION  
       [0009]     Accordingly, the present invention is directed to an orthopedic device or brace for the ankle or foot.  
         [0010]     An object of the present invention is to promote the proper position of the ankle or foot when landing on the foot to prevent knee injuries including ligament injuries.  
         [0011]     The present invention provides an ankle brace or foot support device that provides resistance to dorsiflexion (flexion). The brace has several advantages over a knee brace in terms of preventing an ACL injury including: (1) If the ankle is properly positioned in plantarflexion (extension) at landing, a reflex automatically places the knee in flexion often avoiding the vulnerable knee position; (2) Patients are usually more compliant in wearing ankle braces since they are less cumbersome than large bulky knee braces; and (3) The ankle brace could be designed to have the dual purpose of providing medial and lateral ankle support to reduce the incidence of ankle sprains. For clarification, dorsiflexion is movement of the foot or toes upward toward the front of the shin and plantarflexion is movement of the foot or toes downward away from the front of the shin.  
         [0012]     The present invention provides an ankle brace comprising: (1) a lower leg assembly adapted to be worn on a user&#39;s lower leg; (2) a foot assembly adapted to be worn on the user&#39;s foot; and (3) at least one hinge rotatably connecting said lower leg assembly to said foot assembly, wherein said at least one hinge provides a force on said foot assembly to prevent dorsiflexion and/or to promote plantarflexion. The lower leg assembly may be comprised of a flexible sleeve and/or a pair of brace panels and at least one strap or any combination thereof. The foot assembly may be comprised of a flexible sleeve, a plastic molded form with or without padding, or panels and straps.  
         [0013]     To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, in one aspect of the present invention there is provided an ankle or foot brace for providing a resistance to the foot to properly position the foot for landing on the forefoot thereby preventing knee injuries.  
         [0014]     Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0015]     The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated herein, and constitute a part of this specification and illustrate embodiments of the invention. The figures with the description serve to explain the principles of the invention.  
         [0016]      FIG. 1  is a front elevation view of an ankle brace embodying the present invention positioned on a user&#39;s ankle.  
         [0017]      FIG. 2  is a side elevation view of the ankle brace shown in  FIG. 1 .  
         [0018]      FIG. 3  is an isometric view of portions of the ankle brace shown in  FIG. 1 .  
         [0019]      FIG. 4  is a partial view of the ankle brace shown in  FIG. 1 .  
         [0020]      FIG. 5  is a side elevation view of an ankle. 
     
    
     DETAILED DESCRIPTION  
       [0021]     The system of the present invention will now be described in conjunction with  FIGS. 1-5 .  
         [0022]     The present invention provides a new ankle brace  10  or support which provides a gradually increasing resistance to ankle dorsiflexion to decrease the likelihood of knee injuries. As previously indicated, research has shown that knee injuries to the ACL are often tracked back to improper landing on a flat foot or on the heel with the knee close to extension and in valgus. The present invention provides an ankle brace  10  which provides an appropriate resistive force to the foot  20  or ankle joint  22  to properly position the foot  20  to land on the forefoot thereby preventing common knee injuries.  
         [0023]     As seen in  FIGS. 1-5 , the brace  10  includes a standard pair of panels  14 ,  16  on the medial  24  and lateral  26  aspects of the ankle  22 . In addition, the brace  10  contains a dorsum panel  18  that covers the dorsum  28  (top) of the foot  20 . In the preferred embodiment, the dorsum panel  18  is made from molded plastic and includes padding to protect the wearer&#39;s foot  20 . The preferred embodiment also includes side panels  14 ,  16  which are connected to the dorsum panel  18  through one or more hinges  30  located on one or both of the side panels  14 ,  16 . The side panels  14 ,  16  may be cast or molded plastic to fit the wearer&#39;s inside ankle or leg portion  24  and outside ankle and leg portion  26 . The hinge  30 , at the bottom portion of side panels  14 ,  16 , is connected to the dorsum panel  18  by arms, support straps, or rods  31 ,  33 . The dorsum panel  18  provides a resistance to the top of the foot  28  which helps the user to resist dorsiflexion and/or promote plantarflexion so the wearer is more likely to land on the forefoot. The brace  10  may also employ a heel pad or support  25  connected to the side panels  14 ,  16  to provide more rigidity to the ankle brace.  
         [0024]     The hinge  30  may be a mechanical hinge such as a spring biased hinge or frictional teeth and gear hinge, an air or gas pressured hinge, or other known hinge designs capable of providing the necessary resistance or force. An example of a mechanical hinge assembly which might be employed is provided in U.S. Pat. No. 6,527,733 which is incorporated herein by reference in its entirety. Further, as seen in  FIG. 4 , the hinge  30  may provide a void  35  and/or mechanical wedge which enables the user to vary the degree or amount of resistance to dorsiflexion.  
         [0025]     The mean ankle dorsiflexion and plantarflexion in males age 20 to 59 is 26.1+/−6.5 and 40.5+−8.1 respectively (Nigg). In females age 20 to 59 the mean dorsiflexion and plantarflexion is 24.9+−6.1 and 44.4+/−7.7 respectively (Nigg). As seen in  FIG. 5 , the foot can dorsiflex in an upward angle  51  above the horizontal plane  52  or plantarflex in a downward angle  53  below the horizontal plane  52 . The ankle or foot brace  10  of the present invention may provide a gradually increasing resistance to ankle dorsiflexion as the foot moves from a plantarflexed to a dorsiflexed position. With usage and test data the resistance levels at various degrees of dorsiflexion and plantarflexion can be determined for a user providing variances in the resistance levels based upon the angle of the foot to optimize the brace  10  to prevent common injuries to the knee. In the preferred embodiment, the ankle brace  10  will not provide resistance until the user has moved the ankle past some pre-set range of motion or angle  55  ( FIG. 5 ) below the horizontal plane  52 , such as a set angle within the range of minus 5 to minus 25 degrees dorsiflexion (or +5 to 25 degrees plantarflexion). This would allow the user some movement and flexibility of the ankle  22  without strong resistance but promote proper foot placement.  
         [0026]     The dorsum panel  18  may be made of plastic, fabric, leather, or any other appropriate material or substance. The dorsum panel  18  may be adjustable or of a material that can be form fitted for the user of the brace  10  such as neoprene, injection molded plastic, or other similar materials. Further, the dorsum panel  18  may be larger, smaller, or of a different shape than that specifically depicted in the figures. Further, the dorsum panel  18  may be adjustable in shape and size or easily removed from the brace  10  to allow the wearer to attach different size and shape dorsum panels  18 . The brace  10  may be formed as a one or multi-pieced sleeve or sock such as a neoprene sleeve. In one embodiment, the side panels  14 ,  16  are fitted and secured to the user&#39;s ankle  22  using adjustable straps  61 ,  62 . These adjustable straps  61 ,  62  may employ known adjustment features such as the use of hook and loop or Velcro type elements to adjust and secure the straps  61 ,  62  to the proper size for the user&#39;s ankle  22 . Still further, the side panels  14 ,  16  may be custom fitted using molded plastic such that the panels  14 ,  16  and straps  61 ,  62  can be properly fitted for each individuals ankle  22 . Further, the side panels  14 ,  16  could be formed with molded strap protrusion sections  45 ,  47  which allow the straps  61 ,  62  to be threaded through the side panels  14 ,  16  while maintaining a form fit.  
         [0027]     In addition, the present invention can employ the use of sensors would be located on the bottom of the brace such as at the sole of the foot. The sensor or sensors would detect the removal or a reduction in pressure. The sensor upon sensing a pressure reduction would notify and therefore activate the hinge  30  to begin increasing resistance or to apply a force to dorsum panel  18 . The sensors would enhance the brace  10  such that no force is applied to the dorsum panel  18  to promote plantarflexion when the user&#39;s foot  20  is on the ground but would activate the hinge  30  when the user&#39;s foot  20  is in motion and off of the ground. Still further, the sensor could include a time delay such that the hinge  30  is only activated after some amount of time has lapsed after the pressure on the foot  20  has been reduced or removed. For example, if the average time between normal walking steps is 1 second but the average time between athletic running and jumping steps is 1.4 seconds the ankle brace  30  could employ a delay (i.e. 1 second) between when the sensor senses a reduction or removal in pressure and the hinge  30  provides a resistance or applies a force to the user&#39;s foot.  
         [0028]     The brace  10  could also employ learning technology which measures and learns the user&#39;s use profile such that it measures the user&#39;s typical walking gate or time between steps and calculates or adds a pre-determined time delay on top of the measured walking time to determine the appropriate delay before the hinge  30  provides a resistance or begins to apply force. Still further, the sensors need not be on the brace  10  and could be employed on or in the user&#39;s shoe, sock, or some neoprene type sleeve where the sensor is in communication with the brace  10  and/or hinge  30 .  
         [0029]     While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.