Ulnar collateral ligament: differentiation of displaced and nondisplaced tears with US.

Abstract

To determine the usefulness of ultrasound (US) in the differentiation of displaced and nondisplaced tears of the ulnar collateral ligament (UCL). A 7.5-10-MHz linear-array transducer was used to examine 69 patients in whom a UCL tear was suspected, 43 of whom also underwent surgery. The US findings were compared with those obtained at surgery. Results of US corresponded to results of surgery in 37 of 43 patients. Findings were false-positive in six patients. Twenty-six patients were treated conservatively with thumb casts. These patients showed stability and free range of motion at the first metacarpophalangeal joint at clinical follow-up (9-13 months). Sonography is useful for evaluating nondisplaced and retracted tears of the UCL and determining the need for surgery.