Toe joint replacement models

Abstract

In various embodiments, provided are implantable devices for replacing all or a portion of a metatarsophalangeal joint, comprising (i) a metatarsal component comprising a substantially convex bearing surface; or (ii) a phalanx component comprising a substantially concave bearing surface; or (iii) both. In various embodiments, also provided are methods of treating hallux valgus by replacing all or a portion of a metatarsophalangeal joint with one or more of the provided implantable devices.

1 . An implantable device for replacing all or a portion of a metatarsophalangeal joint, comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface; 
 a base member adapted to be fixed within the metatarsal bone; and 
 a locking member adapted to mechanically join the metatarsal articulation member to the base member; 
   (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface; 
 a base member adapted to be fixed within the phalanx bone; and 
 a locking member adapted to mechanically join the phalanx articulation member to the base member; 
   wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.   
     
     
         2 . A device according to  claim 1 , comprising a material of composition selected from ultra-high molecular weight polyethylene, stainless steel, titanium, titanium alloy, chromium-cobalt-molybdenum alloy, pyrocarbon, and combinations thereof. 
     
     
         3 . An implantable device for replacing all or a portion of a metatarsophalangeal joint, comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface and a stem adapted to receive a portion of a locking member; 
 a base member adapted to be fixed within the metatarsal bone, the base member comprising a cavity adapted to receive at least a portion of the stem and a portion of the locking member; and 
 a locking member adapted to be received by the stem and cavity; 
 wherein when the stem is received in the cavity and the locking member is received by the stem and cavity, the metatarsal articulation member is mechanically joined to the base member; 
   (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface and a stem adapted to receive a portion of a locking member; 
 a base member adapted to be fixed within the phalanx bone, the base member comprising a cavity adapted to receive at least a portion of the stem and a portion of the locking member; and 
 a locking member adapted to be received by the stem and cavity; 
 wherein when the stem is received in the cavity and the locking member is received by the stem and cavity, the phalanx articulation member is mechanically joined to the base member; 
   wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.   
     
     
         4 . A device according to  claim 3 , wherein at least one of the stem of the metatarsal component and the stem of the phalanx component comprises a slot adapted to receive at least a portion of a locking member. 
     
     
         5 . A device according to  claim 4 , wherein at least one of the cavity of the metatarsal component and the cavity of the phalanx component comprises a slot adapted to receive at least a portion of a locking member. 
     
     
         6 . A device according to  claim 4 , wherein the locking member is a flexible spring member adapted to be received within the slot of an articulation member and the slot of a base member of a metatarsal component or a phalanx component. 
     
     
         7 . A device according to  claim 3 , wherein the base member of the metatarsal component, the base member of the phalanx component, or both have a shape selected from cylindrical, conical, or tapered. 
     
     
         8 . A device according to  claim 7 , wherein at least one of the base members comprises one or more peripherally positioned flanges adapted to be received within a cavity of a resected bone. 
     
     
         9 . A device according to  claim 8 , wherein the flanges are flexible spring members that, when inserted into the cavity, exert sufficient tension to fix the base member within the bone. 
     
     
         10 . A device according to  claim 9 , comprising four equidistant longitudinally positioned flanges. 
     
     
         11 . A device according to  claim 3 , comprising a material of composition selected from ultra-high molecular weight polyethylene, stainless steel, titanium, titanium alloy, chromium-cobalt-molybdenum alloy, pyrocarbon, and combinations thereof. 
     
     
         12 . An implantable device for replacing all or a portion of a metatarsophalangeal joint, comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface and a locking member; 
 a base member adapted to be fixed within the metatarsal bone, the base member comprising a cavity adapted to receive the locking member; 
 wherein when the locking member is received by the cavity, the metatarsal articulation member is mechanically joined to the base member; 
   (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface and a locking member; 
 a base member adapted to be fixed within the phalanx bone, the base member comprising a cavity adapted to receive the locking member; 
 wherein when the locking member is received by the cavity, the phalanx articulation member is mechanically joined to the base member; 
   wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.   
     
     
         13 . A device according to  claim 12 , wherein the base member of the metatarsal component, the base member of the phalanx component, or both have a shape selected from cylindrical, conical, or tapered. 
     
     
         14 . A device according to  claim 13 , wherein at least one of the base members comprises one or more peripherally positioned flanges adapted to be received within a cavity of a resected bone. 
     
     
         15 . A device according to  claim 14 , wherein the flanges are flexible spring members that, when inserted into the cavity, exert sufficient tension to fix the base member within the bone. 
     
     
         16 . A device according to  claim 15 , comprising four equidistant longitudinally positioned flanges. 
     
     
         17 . A device according to  claim 12 , comprising a material of composition selected from ultra-high molecular weight polyethylene, stainless steel, titanium, titanium alloy, chromium-cobalt-molybdenum alloy, pyrocarbon, and combinations thereof. 
     
     
         18 . An implantable device for replacing all or a portion of a metatarsophalangeal joint, comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface and a cavity adapted to receive at least a portion of a locking member; 
 a base member adapted to be fixed within the metatarsal bone, comprising a head portion, a body portion, and a continuous cavity; and 
 a locking member adapted to be at least partially received by the metatarsal articulation member cavity; 
 wherein when the locking member is received within the metatarsal articulation member cavity, the metatarsal articulation member is mechanically joined to the base member; 
   (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially convex bearing surface and a cavity adapted to receive at least a portion of a locking member; 
 a base member adapted to be fixed within the phalanx bone, comprising a head portion, a body portion, and a continuous cavity; and 
 a locking member adapted to be at least partially received by the phalanx articulation member cavity; 
   wherein when the locking member is received within the phalanx articulation member cavity, the phalanx articulation member is mechanically joined to the base member;   wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.   
     
     
         19 . A device according to  claim 18 , wherein the body portion of the metatarsal component, the body portion of the phalanx component, or both have a shape selected from cylindrical, conical, or tapered. 
     
     
         20 . A device according to  claim 18 , wherein the continuous cavity of the metatarsal component, the continuous cavity of the phalanx component, or both is adapted to receive a screw member that, when received within the continuous cavity, causes the body portion to expand and exert sufficient tension to fix the base member within the bone. 
     
     
         21 . A device according to  claim 20 , wherein the locking member is at least a portion of the screw member. 
     
     
         22 . A device according to  claim 20 , wherein the locking member is at least one pair of flanges opposably positioned on the head portion. 
     
     
         23 . A device according to  claim 20 , comprising a material of composition selected from ultra-high molecular weight polyethylene, stainless steel, titanium, titanium alloy, chromium-cobalt-molybdenum alloy, pyrocarbon, and combinations thereof. 
     
     
         24 . An implantable device for replacing all or a portion of a metatarsophalangeal joint, comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface; and 
 a locking member comprising a screw thread adapted to fix the metatarsal component in the metatarsal bone; 
   (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface; and 
 a locking member comprising a screw thread adapted to fix the phalanx component in the phalanx bone; 
   wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.   
     
     
         25 . A device according to  claim 24 , comprising a material of composition selected from ultra-high molecular weight polyethylene, stainless steel, titanium, titanium alloy, chromium-cobalt-molybdenum alloy, pyrocarbon, and combinations thereof. 
     
     
         26 . An implantable device for replacing all or a portion of a metatarsophalangeal joint, comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex parabolic bearing surface terminating at equidistantly positioned ends; 
   (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface; 
   wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.   
     
     
         27 . A device according to  claim 26 , comprising a material of composition selected from ultra-high molecular weight polyethylene, stainless steel, titanium, titanium alloy, chromium-cobalt-molybdenum alloy, pyrocarbon, and combinations thereof. 
     
     
         28 . A method of treating hallux valgus, comprising surgically replacing a metatarsophalangeal joint with an implantable device selected from:
 (I) an implantable two-component device comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface; 
 a base member adapted to be fixed within the metatarsal bone; and 
 a locking member adapted to mechanically join the metatarsal articulation member to the base member; and 
 
 (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface; 
 a base member adapted to be fixed within the phalanx bone; and 
 a locking member adapted to mechanically join the phalanx articulation member to the base member; 
 
 wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint; 
   (II) an implantable two-component device comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex bearing surface; and 
 a locking member comprising a screw thread adapted to fix the metatarsal component in the metatarsal bone; 
 
 (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface; and 
 a locking member comprising a screw thread adapted to fix the phalanx component in the phalanx bone; 
 
 wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint; and 
   (III) an implantable two-component device comprising:
 (i) a metatarsal component for surgical implantation into the distal end of a metatarsal bone, comprising:
 a metatarsal articulation member comprising a substantially convex parabolic bearing surface terminating at equidistantly positioned ends; 
 
 (ii) a phalanx component for surgical implantation into the proximal end of a proximal phalanx bone, comprising:
 a phalanx articulation member comprising a substantially concave bearing surface; 
 
 wherein the metatarsal component and the phalanx component are adapted to cooperatively engage when implanted such that the metatarsal articulation member and the phalanx articulation member may move with respect to each other and collectively serve as a prosthetic metatarsophalangeal joint.