Hematoma and distraction arthroplasty for thumb basal joint osteoarthritis: minimum 6.5-year follow-up evaluation.

PURPOSE: Although hematoma and distraction arthroplasty has been found to be successful in the treatment of thumb basal joint arthritis in the short term, questions about its efficacy in the long term have been raised. The goal of the present study was to evaluate the results of this procedure in patients at least 6.5 years after surgery.

METHODS: Twenty-two thumbs from 22 patients from a single surgeon's practice were entered into a prospective single-arm study for surgical treatment of basal thumb arthritis. Treatment consisted of piecemeal excision of the entire trapezium and 5 weeks of K-wire immobilization of the thumb metacarpal in opposition and slight distraction. No ligament reconstruction or tendon interposition was used. Motion, strength, standardized dexterity tests, stress radiographs, and outcome questionnaires including the Arthritis Impact Measurement Scales 2 were evaluated before surgery and at 6, 24, and at least 79 months after surgery.

RESULTS: At 6 months after surgery, 17 of 22 patients reported complete pain relief, and at the most recent follow-up evaluation (average, 88 months after surgery) 18 patients were entirely pain free. Range-of-motion evaluation at the most recent follow-up evaluation showed 21 of 22 thumbs adducted fully into the plane of the palm, and 21 of 22 opposed to the small finger metacarpal head. Comparisons between preoperative and the recent postoperative strength measurements showed an average of 21% increase in grip strength and tip pinch strength, and an 11% increase in key pinch strength over preoperative values. Although the radiographically determined scaphoid-thumb metacarpal distance decreased with time from surgery, no correlation with strength or functional outcome measurements was found. The Arthritis Impact Measurement Scales 2 data showed postoperative improvement in the hand and finger function and arthritis pain scales.

CONCLUSIONS: After trapezial excision, K-wire immobilization in a slightly overcorrected position without formal interposition or ligament reconstruction allows for restoration and maintenance of a stable, pain-free thumb that has comparable strength and motion with published reports of more complicated interventions over comparable time periods.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV.