Free palmaris longus graft tenodesis effectively treats swan neck adduction collapse secondary to thumb basilar joint arthritis

Background: Compensatory thumb metacarpophalangeal joint hyperextension may occur with basilar joint arthritis and subluxation. Instability at the metacarpophalangeal joint must be corrected when the basilar joint is operated on. The authors use a simple surgical procedure that provides correction of thumb metacarpophalangeal joint hyperextension by a free palmaris longus graft to provide volar tenodesis across the metacarpophalangeal joint. Methods: Twelve patients (14 extremities) were evaluated at a minimum of 11 months postoperatively. Outcome analysis was performed using the Disability of the Arm, Shoulder, and Hand Questionnaire, the McGill Pain Questionnaire, and a patient satisfaction survey. Clinical assessments evaluated thumb appearance, range of flexion and extension at the metacarpophalangeal joint, opposition, span, and cylindrical grip strength and pinch strength. Special attention was devoted to stability of the metacarpophalangeal joint while maintaining range of motion and strength. Results: The average score on the Disability of the Arm, Shoulder, and Hand Questionnaire was 13.0 (good return of function), and the McGill Pain Questionnaire revealed mild to no postoperative pain. Overall postoperative patient satisfaction was high. There was good range of motion at the metacarpophalangeal joint (mean flexion, 44 degrees), and assessment of thumb strength revealed a mean tip pinch strength of 6.8 pounds and a mean key pinch strength of 8.7 pounds. Firm thumb stability was demonstrated during these strength measurements. Conclusions: Thumb metacarpophalangeal joint tenodesis can be an alternative to arthrodesis in patients who have swan neck deformity of the thumb secondary to basilar joint arthritis. It has the advantage of retaining useful motion. The procedure provides high patient satisfaction and good thumb function, strength, and range of motion. It is easily performed simultaneously with trapezial resection arthroplasty without complications.