Bone implants for orthopedic procedures and corresponding methods

Abstract

Implants and procedures far joint fusion make use of implants comprising cortical bone. The implants have lamellae that are generally aligned. In some embodiments, the implants can have indicia that indicate the alignment of the lamellae within the joint. In some embodiments, the implants comprise a plurality of implant elements, with the implant elements oriented so that the lamellae of the elements are aligned with each other. The implants can be inserted into a joint with the lamellae aligned across the joint to resist compression or deforming forces of the joint and to provide for improved implant strength. In some embodiments, the implants can be inserted into a joint over a pin and/or through a cannula to help guide the implant to the implant site within the joint. In some embodiments, the implants can be desirably formed from bone plugs harvested from long bones.

What is claimed is: 
     
         1 . A method for making a bone implant element, the method comprising:
 machining a surface of a generally cylindrical bone plug cut from the wall of a long bone to form a concave surface with cortical bone; and marking the orientation of lamellae in the bone.   
     
     
         2 . The method of  claim 1  wherein the marking comprises forming a visual indication on a side surface of the bone plug and/or a top surface of the bone plug. 
     
     
         3 . The method of  claim 1  wherein the marking comprises forming a distinctive shape that provides a corresponding orientation of lamellae through orientation of the shape. 
     
     
         4 . The method of  claim 1  comprising machining the bone plug to form a channel through the bone plug between a top surface and a bottom surface. 
     
     
         5 . The method of  claim 1  comprising machining a side, top or bottom surface of the bone plug to form a textured side surface, top surface, bottom surface, combinations thereof or portions thereof. 
     
     
         6 . The method of  claim 1  comprising machining a side surface of the bone plug to form a tapered bone element. 
     
     
         7 . A method for immobilizing a joint, the method comprising:
 inserting, a bone implant through a cannula having a generally cylindrical inner surface into a joint, the bone implant oriented with lamellae oriented within 20 degrees of an axis orthogonal to the surface bisecting the joint, wherein the bone implant has a longitudinal side surface that is generally cylindrical with the bone implant being inserted with the generally cylindrical side surface sliding within the cannula.   
     
     
         8 . The method of  claim 7  wherein the bone implant comprises a visual indicator indicating the orientation of the lamellae in the bone implant. 
     
     
         9 . The method of  claim 7  wherein the bone implant comprises a plurality of bone implant elements configured in a stacked configuration. 
     
     
         10 . The method of  claim 9  wherein the implant elements comprise a visual indicator indicating the orientation of the lamellae in the implant element and wherein the visual indicators are aligned. 
     
     
         11 . The method of  claim 7  wherein bone implant comprises a channel configured to receive a pin and extending through the implant between a top surface and a bottom surface and wherein the inserting comprises inserting the implant over a pin into the joint. 
     
     
         12 . The method of  claim 7  comprising orienting the bone implant with the lamellae oriented within 20 degrees of the axis orthogonal to the surface bisecting the joint. 
     
     
         13 . The method of  claim 7  wherein the bone element implants comprise a certain shape, such that, under compression, the resulting cylinder formed has a rough, notched or irregular side surface. 
     
     
         14 . The method of  claim 7  where the implant is chemically treated with acid or coated with hydroxyapatite to form surface texturing.