Ulnar collateral ligaments are found in the thumb, wrist, and elbow regions. In the thumb, the ulnar collateral ligament runs beside the metacarpophalangeal joint. If injured, the thumb may be immobilized for treatment. This ligament is not the same as the ulnar collateral ligament of the wrist. The ulnar collateral ligament of the wrist joint is a rounded cord. It attaches to the end of the ulna's styloid process. This ligament is not to be confused with the ulnar collateral ligament of the elbow, which is a thick, triangular band. This band has two sections: anterior and posterior. The anterior is attached to the front part of the medial epicondyle of the humerus. The posterior section is attached to the lower and back section of the medial epicondyle. An injury of the ulnar collateral ligament of the elbow can be either due to a slow deterioration or an acute rupture. Stress on the ulna will cause slow deterioration, while collisions may cause an acute rupture.