Purpose: Trauma to the radial collateral ligaments requires the same attention as trauma to the ulnar ligaments. Damage is uncommon due to the particular anatomic position, but nevertheless a distinct clinical entity.

Material and methods: We report a retrospective analysis of 14 patients, eight who underwent emergency surgery and six with trauma sequelae. Mean follow-up was 22 months and mean age 37 years. Among the recent lesions, the pain score (scale from 1 to 5) was 4.5) and the instability score (scale from 1 to 3) was 3. Palmar subdislocation was 4.8 mm and laxity was 16.7°. Among the old lesions (> 1 month) the corresponding data were pain 3.3, instability 2.5, palmar sub-dislocation 4.2 mm, laxity 19.1°. Two patients had signs of osteoarthritis. At surgery, the phalanx and metacarpus were equally injured. Associated lesions (capsule, short abductor) were present in 78% of the patient. The radial collateral ligaments and the soft tissue were reinserted or retightened in all cases. One patients required arthrodesis due to cartilage damage.

Results: Among the recent injuries, 71% reached a good subjective result: amplitude loss (flexion/extension) was 17°, force was 75% and laxity was 5°. Two patients had palmar subdisloction. Among the older lesions, a good subjective result was achieved in 66%: loss of amplitude case 32°, force was 69% and laxity was 8°. Palmar subdislocation was 2 mm on the average. We had two cases of persistent dysaesthesia.

Discussion: Radial injury appears to be falsely benign because the Stener lesion is not found on this side of the metacarpophalange. The importance of the injury in these traumas is related to the vulnerability of the dorsal region of the medial collateral ligament and is probably the cause of poor outcome after surgery for older lesions with palmar dislocation which is difficult to correct. We advocate emergency surgery for a wide range of indications. We always operate major radial laxity (> 35°) or laxity associated with palmar subdislocation. For other cases, we use the anterior forced drawer view to disclose potential associated dorsal injury.