Hematoma and distraction arthroplasty for thumb basal joint osteoarthritis: a prospective, single-surgeon study including outcomes measures.

PURPOSE

Many surgeons have abandoned the simple trapeziectomy as a surgical treatment option for thumb basal joint arthritis secondary to reports of postoperative weakness. The thumb metacarpal subsiding into the trapezial void has been proposed as the causative factor. The goal of the present study was to evaluate the results of trapeziectomy and postoperative K-wire immobilization of the thumb metacarpal in a distracted position without the use of ligament reconstruction or tendon interposition.

METHODS

Twenty-six thumbs in 26 patients from a single surgeon's practice were entered into a prospective single-arm study for surgical treatment of peritrapezial arthritis. Treatment consisted of piecemeal excision of the entire trapezium and 5 weeks of K-wire immobilization of the first metacarpal in slight distraction and opposition. No ligament reconstruction or tendon interposition was used. Motion, strength, stress radiographs, standardized dexterity tests, and outcomes questionnaires including the Arthritis Impact Measurement Scales 2 (AIMS2) were evaluated before surgery and 6 and 24 months after surgery.

RESULTS

At 6 months 19 of 26 patients (73%) reported complete relief of pain and at 24 months 92% were entirely pain free. Range of motion evaluation showed 24 of 26 thumbs adducted fully into the plane of the palm and 25 of 26 opposed to the fifth metacarpal head. Comparisons between preoperative and 24-month postoperative strength measurements showed an average 47% increase in grip strength, 33% increase in key pinch strength, and a 23% increase in tip pinch strength over preoperative values. AIMS2 data showed postoperative improvement in "hand and finger function" and "arthritis pain" scales.

CONCLUSIONS

After trapezial excision K-wire immobilization in a slightly overcorrected position without tissue interposition or ligament reconstruction restores a stable, pain-free thumb that has superior strength and motion compared with published reports of the more complicated interventions.