[Injuries and posttraumatic osteoarthritis of the first carpometacarpal joint].

BACKGROUND: Precise function of the hand is crucially characterized by opposition movement of the thumb, only possible because of the functional anatomy of the first carpometacarpal joint. High functional demands to this joint consequently lead to the highest rate of osteoarthritis of the hand joints and loss of function. Carpometacarpal (CMC) osteoarthritis of the thumb is rarely seen in posttraumatic cases. It can be caused by fractures involving the joint surfaces of both, the trapezium or the first metacarpal, whereas dislocations of the carpometacarpal joint itself only occasionally lead to osteoarthritis.

OBJECTIVES: Identification and compilation of current concepts in diagnosis and therapy of posttraumatic carpometacarpal osteoarthritis of the thumb.

METHODS: Selective PubMed and Cochrane review, data obtained from own patient investigations and author's experiences were used.

RESULTS: Adequate treatment of the injury will minimize the risk for future malfunction. In early stages, arthroscopy is a valuable method for the diagnosis and treatment of posttraumatic rhizarthrosis. For all stages, a multitude of operative procedures are described and being used but yet not finally assessed for effectiveness. Advanced osteoarthritis of the first CMC joint is widely treated by trapeziectomy, which is suitable for most patients, and considered as gold standard. Additional procedures like suspension, interposition or k-wire transfixation do not provide any significant advantage and lead to comparable results. It is advisable to treat hyperextension of the metacarpophalangeal joint of the thumb at any stage of CMC osteoarthritis.