This invention provides methods for optimal implantation of a solid substrate for promoting cell or tissue growth or restored function in an osteochondral, bone or cartilage tissue in a subject in need thereof. The methods include selecting and preparing a solid substrate for promoting cell or tissue growth or restored function for implantation, which solid substrate has a length and width or that promotes a tight fit within the boundaries of the implantation site and is further characterized by a height sufficient such that when a first terminus of said solid substrate is implanted within a bone in a site for implantation, a second terminus of said solid substrate is at a height at least 2 mm less than an articular cartilage layer surface or is proximal to a tide mark region in said implantation site and optionally applying a biocompatible polymer layer to an apical surface of said implant, which layer does not exceed the articular cartilage layer surface in height. Tools for implementation of optimal positioning are described including a unique tool (5-120) for trimming cartilage at the implantation site.
