Ulnar nerve palsy after supracondylar humerus fracture.

Six patients with cubitus varus deformity after a supracondylar fracture of the humerus had ulnar nerve palsy 7 (3-14) years following the fracture. All the patients showed anterior dislocation of the ulnar nerve during elbow flexion. In cubitus varus deformity, medial shifting of the triceps muscle occurs, which pushes the ulnar nerve anteriorly and frequently causes ulnar-nerve dislocation. Five of the 6 patients underwent surgery with subsequent improvement.