Trends in Trapeziometacarpal Implant Design: A Systematic Survey Based on Patents and Administrative Databases.

Hand function is inseparably linked to the condition of the thumb. The trapeziometacarpal (TMC) joint that provides the different movements of opposition is one of the joints most affected by osteoarthritis, which causes an irreversible deformation of the bone. The ideal thumb carpometacarpal implant must restore range of movement, prevent complications, be biocompatible, and have good mechanical properties (ie, low wear, high corrosion resistance, and osteointegration properties where it is anchored in a bone). The integrity of the implant and the surrounding biological structures must be long-lasting and withstand constant stresses induced by the prosthesis. Three main types of implant systems for the thumb are currently clinically available; others are under investigation in human subjects. This systematic review is based on administrative databases, patents, the literature, and information from orthopedic companies. It provides a summary of strategies and design changes and an overview of the biomechanical characteristics of currently available carpometacarpal implants for treating osteoarthritis of the thumb.