Inveterate lesions of the collateral ligaments of the thumb joints.

Inveterate lesions 2-18 months following injury to the collateral ligaments of the metacarpophalangeal (MP) joint of the thumb and pollicised proximal interphalangeal (PIP) joint were replaced by a tendinous transplant from the palmaris longus muscle. The group comprised three patients, 34-46 years old, with a post-traumatic injury of the ulnar collateral ligament of the MP joint of the thumb and a seven-year-old child with an congenital defect of the radial collateral ligament. Lateral 30-degree instability indicates injury of the collateral ligament. On examination the range of instability in the investigated group was between 45 and 90 degrees. The authors recommend comparison with the contralateral thumb.