A Quantitative Evaluation of Thumb Function after Ulnar Collateral Repair and Reconstruction

Injuries to the ulnar collateral ligament of the thumb metacarpophalangeal joint are common and have received considerable recent attention in the literature. Against this increased diagnostic awareness stand surgical repair results, which lack objective criteria. Most authors confine their results to good, bad, or indifferent. We are presenting a followup series of acute primary repairs (under 2 weeks) and late reconstructive repairs. All followup intervals were longer than 6 months (mean, 23 months). Fifteen patients had primary repair: 23 patients had late reconstruction. The age range of the patients was 14 to 62 years (mean, 28 years). Forty per cent of the primary repairs involved a fragment of bone. The two most common types of reconstruction, that using a free tendon graft and that of adductor advancement, are similarly compared. Results were evaluated using range of motion, pinch strength, and radiographs as well as standard subjective criteria, and compared to the normal contralateral thumb. Primary repair achieved 92% of normal pinch strength and 84% of normal thumb motion. Both reconstructive techniques yielded adequate pinch strengths although the adductor advancement (85%) was somewhat greater than the free tendon graft (81%). Range of motion was significantly more restricted in the adductor group (65%) than in the free graft group (78%). Subjectively 15% of patients complained of aching with use of the thumb and 8% complained of weakness and 2% of residual instability. Eleven per cent of the patients with the free graft complained of the increased bulk over the reconstructed area of their thumb. Complications included one rerupture of a primary repair at 10 weeks requiring reconstruction, one failure of an adductor advancement secondary to pullout at 4 weeks during a cast change, one patient with dyesthesias in the dorsal sensory nerve of the thumb that resolved, and one patient with hypertrophic scarring at a palmaris longus graft site. It is clear that primary repair done in the first 2 weeks stabilizes the ulnar side of the metacarpophalangeal joint of the thumb and more closely approaches the function of its contralateral thumb metacarpophalangeal joint. Both reconstructive techniques have their own specific advantages, and both gave adequate functional results. Pinch strength from both tendon graft and adductor advancement were similar but motion was better with the graft. Patients with vocations requiring maximum thumb function, such as in a professional baseball pitcher, may benefit from a combination of the above reconstructive procedures, and these are presented.