Dynamic orthopedic knee brace assembly

Abstract

A knee brace assembly for various uses, e.g., restricting anterior tibial movement. The knee brace assembly includes a proximal cuff for engaging the wearer's leg above the knee and a distal cuff for engaging the wearer's leg below the knee. The proximal and distal cuffs are linked together by a hinge that permits pivotal movement of the proximal cuff relative to the distal cuff. The proximal cuff has lateral and medial portions each having a slot extending there along. A strap guiding assembly is slidably mounted within each of the slots. Each strap guiding assembly is arranged to slide between a proximal extreme when the wearer's leg is in flexion and a distal extreme as the wearer extends his or her leg. A biasing device biases each strap guiding assembly towards its proximal extreme. A cross-strap, having free ends and a length, is provided for engagement with the wearer's leg. The cross-strap attaches to the wearer's leg below the knee and wraps behind the knee in crisscross fashion. The free ends of the strap attach to the strap guiding assembly. The cross-strap is operative in response to extension of the wearer's leg to pull the strap guiding assembly from the proximal extreme towards the distal extreme thus creating a force counteractive to abnormal anterior movement of the tibia.

I claim:  
     
       1. A knee brace assembly for restricting anterior translation of a wearer's tibia, the wearer also having a leg including a thigh, a knee and a leg portion below the knee, said knee brace assembly comprising: 
       a. first means for engaging the wearer's thigh, said first means comprising a lateral portion positioned over the lateral side of the wearer's thigh and a medial portion positioned over the medial side of the wearer's thigh, said lateral and medial portions each having a slot extending there along;  
       b. second means for engaging the wearer's leg portion below the knee;  
       c. hinging means linked to said first and second means to permit pivotal movement of said first means relative to said second means;  
       d. strap guiding means slidably mounted within each of said slots, said strap guiding means being arranged to slide between a proximal extreme when the wearer's leg is in flexion towards a distal extreme as the wearer extends his or her leg;  
       e. biasing means resiliently biasing said movable strap guides towards said proximal extreme; and,  
       f. a cross-strap provided for engagement with the wearer's leg, said cross-strap comprising free ends and a length therebetween, a portion of said length comprising tibial pressure application means, said cross-strap being attachable over the wearer's leg with said tibial pressure application means located over the wearer's tibia, said cross-strap wrapping behind the wearer's knee in a crisscross manner, the free ends of said cross-strap being attachable to said strap guiding means and in response to extension of the wearer's leg said cross-strap tightening geometrically around the wearer's knee and pulling said strap guiding means from said proximal extreme towards said distal extreme thus enabling said tibial pressure application means to provide resistance to the anterior movement of the tibia.  
     
     
       2. The knee brace assembly of claim  1  wherein said first means comprises a proximal cuff engageable with the wearer's thigh and wherein said second means comprises a distal cuff engageable with the wearer's leg portion below the knee. 
     
     
       3. The knee brace assembly of claim  2  wherein said proximal cuff additionally comprises an arcuate portion for engagement with the anterior portion of the wearer's thigh and said distal cuff additionally comprises an arcuate portion for engagement with the anterior portion of the wearer's leg below the knee. 
     
     
       4. The knee brace assembly of claim  2  wherein said medial and lateral portions of said proximal cuff and said medial and lateral portions of said distal cuff are pivotally connected to said hinging means. 
     
     
       5. The knee brace assembly of claim  2  wherein said biasing means comprises an elastic band anchored at one end to said proximal cuff, said elastic band being connected at its opposite end to said strap guiding means. 
     
     
       6. The knee brace assembly of claim  2  wherein said biasing means comprises a spring anchored at one end to said proximal cuff, said spring being connected at its opposite end to said strap guiding means. 
     
     
       7. The knee brace assembly of claim  6  wherein said spring is a leaf spring. 
     
     
       8. The knee brace assembly of claim  2  wherein said proximal cuff additionally comprises a longitudinal axis, said slots extending parallel to said longitudinal axis. 
     
     
       9. The knee brace assembly of claim  2  wherein said proximal and distal cuffs are formed of lightweight, high-impact thermoplastic material. 
     
     
       10. The knee brace assembly of claim  2  wherein said proximal and distal cuffs are formed of a carbon fiber filament material. 
     
     
       11. The knee brace assembly of claim  2  additionally comprising a sleeve encircling the wearer's leg below the knee, said cross-strap being releasably attachable over said sleeve. 
     
     
       12. The knee brace assembly of claim  11  wherein said distal cuff is engageable with the wearer's leg over said suspension sleeve. 
     
     
       13. The knee brace assembly of claim  2  additionally comprising adjustably tightenable first strap means for engaging said proximal cuff to the wearer's thigh and adjustably tightenable second strap means for engaging said distal cuff to the wearer's leg portion below the knee. 
     
     
       14. The knee brace assembly of claim  13  wherein each of said first and second strap means includes an elastic segment. 
     
     
       15. The knee brace assembly of claim  1  wherein each of said medial and lateral portions comprises a rigid thigh support member engageable with the wearer's thigh and wherein said second means comprises a pair of rigid calf support members engageable with the wearer's leg portion below the knee. 
     
     
       16. The knee brace assembly of claim  1  wherein said cross-strap is non-elastic and adjustably tightenable to selectively vary the magnitude of said force counteractive to abnormal anterior movement of the tibia. 
     
     
       17. The knee brace assembly of claim  1  wherein said hinging means comprises a pair of hinges positioned over the medial and lateral sides of the wearer's knee. 
     
     
       18. The knee brace assembly of claim  17  wherein said proximal and distal cuffs and said hinges are lined with non-allergenic foam padding for direct engagement with the wearer's skin. 
     
     
       19. The knee brace assembly of claim  17  wherein said hinges are polycentric hinges. 
     
     
       20. The knee brace assembly of claim  1  wherein said strap guide means are pivotable. 
     
     
       21. The knee brace assembly of claim  1  wherein said cross-strap is adjustable. 
     
     
       22. A knee brace assembly for restricting anterior translation of a wearer's tibia, said knee brace assembly comprising: 
       
         a. a rigid, inelastic upper cuff adapted to be secured to the thigh;  
       
       
         b. a rigid, inelastic lower cuff adapted to be secured to the leg below the knee;  
       
       
         c. a hinge connecting said upper and lower cuffs to permit rotational movement of said upper cuff relative to said lower cuff;  
       
       
         d. a strap comprising a pair of free ends and an intermediate section therebetween, said intermediate section of said strap being attachable over the wearer's tibia at a location below said hinge and interior of the lower cuff, said strap crossing upon itself, said free ends of said strap attaching to said upper cuff, said strap being arranged to tighten geometrically around the wearer's knee in response to extension of the wearer's leg to apply a force thereto, said force providing resistance to the anterior movement of the tibia. 
       
     
     
       23. The knee brace assembly of claim  22  wherein said strap is formed of a non- elastic flexible web and is adjustably tightenable to selectively vary the magnitude of said force counteractive to abnormal anterior movement of the tibia.   
     
     
       24. The knee brace assembly of claim  22  additionally comprising a sleeve adapted to encircle the wearer's leg below the knee, said strap being releasably securable over said sleeve. 
     
     
       25. The knee brace assembly of claim  22  wherein said cuff additionally comprises a plurality of rings attached thereto, said strap being securable to said cuff by slipping said free ends thereof through said rings and looping said free ends therearound. 
     
     
       26. The knee brace assembly of claim  24  wherein said sleeve comprises a plush exterior surface and wherein said strap includes a hook patch disposed on the length thereof, said hook patch being releasably securable to the plush exterior surface of said sleeve at a position that lies over the wearer's tibia just below the wearer's knee. 
     
     
       27. The knee brace assembly of claim  22  additionally comprising a plurality of straps for securing said cuff to said thigh. 
     
     
       28. A knee brace assembly for restricting anterior translation of a wearer's tibia, said knee brace assembly comprising: 
       
         a. a pair of supports, one of said pair adapted to be secured to the medial side of the leg, the other of said pair adapted to be secured to the lateral side of the leg, each of said pair of supports comprising a rigid, inelastic upper portion adapted to be secured to the thigh and a rigid, inelastic lower portion adapted to be secured to the leg below the knee, each of said pair of supports additionally comprising a hinge connecting said upper and lower portions to permit rotational movement of said upper portion relative to said lower portion;  
       
       
         b. a strap comprising a pair of free ends and an intermediate section therebetween, said intermediate section of said strap being attachable over the wearer's tibia at a location below said hinge and interior of the lower portion of said supports, said strap crossing upon itself, said free ends of said strap attaching to said upper portion, said strap being arranged to tighten geometrically around the wearer's knee in response to extension of the wearer's leg to apply a force thereto, said force providing resistance to the anterior movement of the tibia. 
       
     
     
       29. The knee brace assembly of claim  28  additionally comprising a plurality of straps for securing said pair of supports to the wearer's thigh.