A method for treating arthritis of a joint includes identifying a bone lesion in a bone adjacent to the joint; and implanting in the bone a reinforcing member in or adjacent to the bone lesion. A kit for conducting the method includes: (a) at least one reinforcing member having a proximal face adapted to face the joint, a distal face adapted to face away from the joint, and a wedge-shaped edge adapted to pierce bone, wherein the at least one reinforcing member is planar and sterile; and (b) a container adapted to maintain the at least one reinforcing member sterile. Another kit includes: (a) a sterile fluid; (b) a syringe for injecting the fluid into a bone; (c) a curing agent adapted to cure the fluid to polymerize and/or cross-link; and (d) a container adapted to maintain the sterility of contents of the container.