Degenerative change at the pseudarthrosis after trapeziectomy at 6-year followup.

BACKGROUND: Simple trapeziectomy has a well-documented history of success for the management of osteoarthritis at the trapeziometacarpal joint. There is concern, however, that late-onset failure can occur as a result of the development of degenerative disease at the scaphoid-metacarpal pseudarthrosis.

QUESTIONS/PURPOSES: The purpose of this study was to determine whether (1) radiographic changes of degenerative joint disease progressed; (2) the pseudarthrosis height diminished between 1 year and 6 years after either simple trapeziectomy or trapeziectomy with ligament reconstruction and tendon interposition (LRTI); and 3) the presence of degenerative changes were associated with inferior scores on standardized outcomes instruments.

METHODS: Using cases from an earlier randomized trial, the 1-year and 6-year stress radiographs of the pseudarthrosis between the distal pole of the scaphoid and the base of the thumb metacarpal were assessed for degenerative change in 25 thumbs that had undergone simple excision of the trapezium and 29 that had undergone trapeziectomy + LRTI for painful trapeziometacarpal joint osteoarthritis. Degenerative change was graded according to a Kellgren and Lawrence system, and clinical results were assessed using the Patient Evaluation Measure (PEM), Disabilities of the Arm, Shoulder and Hand (DASH) questionnaires, and thumb key pinch strength.

RESULTS: One of the 29 thumbs treated with trapeziectomy + LRTI and seven of the 25 thumbs treated by simple excision of the trapezium exhibited increased degenerative change at their final followup. A pseudarthrosis space was preserved in 22 of the 25 simple trapeziectomies and 28 of the 29 trapeziectomies + LRTI. The presence of degenerative change did not adversely affect the outcome as measured by the PEM, the DASH, or thumb key pinch strength.

CONCLUSIONS: Increased degenerate-like changes were observed after simple excision of the trapezium but these did not influence the clinical outcome.

LEVEL OF EVIDENCE: Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.