Hand Case 10 ED Management

UCL Thumb Injury

All suspected UCL injuries should be placed in a thumb spica splint and referred to see a hand surgeon. Those with a complete rupture of the UCL (>30 degrees of laxity) or an associated avulsion fx that is >2 mm displaced or involves >20% of the articular surface, should be seen within a few days. With complete UCL rupture, the adductor pollicis longus aponeurosis can also get entrapped between the severed ends of the ligaments, requiring surgery.

If a UCL rupture is untreated, chronic instability of the joint can result. Patients can develop chronic degeneration and decreased pinch strength. If stress testing is limited by pain initially, and the patient is tender over the ulnar base of the proximal phalanx of the thumb, treat as if there is an UCL injury by placing a thumb spica splint and arranging hand surgery follow up.