Internal Joint Distraction Device

Abstract

An internal joint distraction device provides articulation to an articulating bone joint between an upper bone structure and a lower bone structure. The device includes a medial plate shaped to at least partially conform to a medial side of a bone structure of a limb and includes a lateral plate shaped to at least partially conform to a lateral side of a bone structure of a limb. Each of the medial and lateral plates may include a longitudinal length sufficient to extend from the upper bone structure to the lower bone structure thereby spanning at least a portion of the joint. Each plates includes at least one proximal connection feature formed therein for connecting to the upper bone structure and at least one distal connection feature formed therein for connecting to the lower bone structure. An axle extends from one of the connection features on the medial plate to one of the connection features on the lateral plate. The axle extends through one of the upper and lower bone structures in a manner that said one of the upper and lower bone structures pivots about the axle relative to the other of the upper and lower bone structures.

1 . A distraction device that provides articulation to an articulating bone joint between an upper bone structure and a lower bone structure, the device comprising:
 a medial plate shaped to at least partially conform to a medial side of a bone structure of a limb;   a lateral plate shaped to at least partially conform to a lateral side of a bone structure of a limb;   each of the medial and lateral plates having a longitudinal length sufficient to extend from the upper bone structure to the lower bone structure thereby spanning at least a portion of the joint, each of the medial and lateral plates having at least one proximal connection feature formed therein for connecting to the upper bone structure and at least one distal connection feature formed therein for connecting to the lower bone structure; and   an axle extending from one of the connection features on the medial plate to one of the connection features on the lateral plate, the axle extending through one of the upper and lower bone structures in a manner that said one of the upper and lower bone structures pivots about the axle relative to the other of the upper and lower bone structures.   
   
   
       2 . The distraction device of  claim 1 , wherein the medial and lateral plates each have a distal end with a bull-nosed shape. 
   
   
       3 . The distraction device of  claim 1 , wherein the width of the plates increases from a distal most end or a proximal most end toward the joint 
   
   
       4 . The distraction device of  claim 1 , the plates having a plurality of connection features. 
   
   
       5 . The distraction device of  claim 1 , further comprising bone screws having a threaded portion and a head, the threaded portion extending substantially to the head. 
   
   
       6 . The distraction device of  claim 1 , wherein the axle comprises a bone interfacing portion and a plate interfacing portion adjacent the bone interfacing portion, the bone interfacing portion having a non-circular cross-section. 
   
   
       7 . The distraction device of  claim 1 , wherein the medial and lateral plates comprise a plurality of bores, wherein the axle includes plate interfacing portions at each end receivable in the most proximal bores or most-distal bores on the plates. 
   
   
       8 . The distraction device of  claim 7 , wherein at least one of a spherical nut and a captured spherical bushing maintains the axle within the connection features on the plates. 
   
   
       9 . The distraction device of  claim 1 , wherein the medial plate comprises a socket portion shaped to interface with and receive a portion of the upper bone structure. 
   
   
       10 . The distraction device of  claim 1 , wherein one of the medial and lateral plates comprises a bone interfacing surface and an offset bearing surface, the offset bearing surface being configured to both bear on the axle and bear on the adjacent one of the upper and lower bone structure. 
   
   
       11 . The distraction device of  claim 10 , wherein the axle includes a bone interfacing surface disposed such that the offset bearing surface abuts against the bone interfacing surface of the axle 
   
   
       12 . The distraction device of  claim 11 , wherein one of the medial and lateral plates further comprises a shoulder extending between the bone interfacing surface and the offset bearing surface, the shoulder being arranged and configured to bear at least a portion of the weight of the patient. 
   
   
       13 . The distraction device of  claim 12 , wherein the offset bearing surface is a cylindrical boss and the shoulder is formed of a cylindrical side of the cylindrical boss. 
   
   
       14 . The distraction device of  claim 1 , further comprising a pin extending from and connecting the medial and lateral plates together, the pin being disposed distal or proximal of the joint and the axle being disposed at the joint. 
   
   
       15 . The distraction device of  claim 1 , further comprising bone screws and a pin connector that connect the medial and lateral plates, wherein the medial and lateral plates each further comprises spherical countersinks. 
   
   
       16 . The distraction device of  claim 1 , wherein the plates, the axle and the entire device is structurally arranged and configured to be internal in the limb. 
   
   
       17 . The distraction device of  claim 1 , comprising a self-contained, internal distraction system. 
   
   
       18 . The distraction device of  claim 17 , wherein the distraction system includes a non-concentric component pivotable to displace the axle relative to the plates. 
   
   
       19 . The distraction device of  claim 17 , wherein the distraction system comprises a spherical bushing and a cylindrical bushing arranged to fit within a connecting feature on the medial and lateral plates. 
   
   
       20 . A distraction device that provides articulation to an articulating bone joint between tibia and fibula bone structures and talus bone structure at an ankle joint, the device comprising:
 a tibia plate shaped to at least partially conform to a medial side of the tibia, the tibia plate having a bone interfacing surface and a socket portion shaped to a receive a portion of the tibia adjacent the ankle joint;   a fibula plate shaped to at least partially conform to a lateral side of the fibula;   each of the tibia and fibula plates having a longitudinal length sufficient to extend from the respective tibia and fibula to lie adjacent the talus when connected in place adjacent to the respective tibia and fibula, each of the plates having at least one proximal connection passage formed therein for receiving a bone screw configured to connect to the tibia or fibula and at least one distal connection passage formed therein for connecting to the talus; and   an axle extending from the distal connection feature on the tibia plate to the distal connection feature on the fibula plate, the axle being arranged to extend through the fibula and the talus, the axle including structural features that prevent relative rotation of the axle relative to the talus while permitting the relative rotation of the axle relative to the tibia and fibula plates.   
   
   
       21 . The distraction device of  claim 20 , wherein the tibia and fibula plates each have a proximal end with a bull-nosed shape. 
   
   
       22 . The distraction device of  claim 20 , wherein the width of the plates increases from a proximal most end toward the joint 
   
   
       23 . The distraction device of  claim 20 , wherein the tibia and fibula plates comprise a plurality of bores, wherein the axle includes plate interfacing portions at each end receivable in the most-distal bores on the plates. 
   
   
       24 . The distraction device of  claim 20 , wherein the tibia plate comprises a bone interfacing surface and an offset bearing surface. 
   
   
       25 . The distraction device of  claim 24 , wherein the axle includes a bone interfacing surface disposed such that the offset bearing surface of the tibia plate abuts against the bone interfacing surface of the axle. 
   
   
       26 . The distraction device of  claim 24 , wherein the tibia plate further comprises a shoulder extending between the bone interfacing surface and the offset bearing surface, the shoulder having a receiving portion shaped to receive a portion of the proximal end of the tibia. 
   
   
       27 . The distraction device of  claim 20 , further comprising a pin extending from and connecting the tibia and fibula plates together, the pin being disposed proximal of the joint and the axle being disposed at the joint. 
   
   
       28 . The distraction device of  claim 20 , comprising a self-contained, internal distraction system. 
   
   
       29 . The distraction device of  claim 28 , wherein the distraction system includes a non-concentric component pivotable to displace the axle relative to the plates. 
   
   
       30 . A treatment method for maintaining a first bone structure in a distracted state, comprising:
 creating a passage through a first bone structure on a first side of an articulating joint, the passage being formed substantially along the axis of the joint;   inserting an axle through the passage;   implanting a first bone plate in contact with and adjacent to one of a medial and lateral side of a second bone structure;   implanting a second bone plate in contact with and adjacent to the other of the medial and lateral sides of the second bone structure; and   connecting the axle to both the first and second bone plates to provide articulating movement of the first bone structure about the axle relative to the second bone structure.   
   
   
       31 - 53 . (canceled)