1. Snapping of the Medial Head of the Triceps and Recurrent Dislocation of the Ulnar Nerve. Anatomical and Dynamic Factors*† by ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am Volume 80(2):239-47 February 1, 1998 ©1998 by The Journal of Bone and Joint Surgery, Inc.

2. Fig. 1 Illustrations showing how the position of the ulnar nerve and the medial head of the triceps can be determined relative to the medial epicondyle as the elbow is flexed and extended actively or passively. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

3. Figs. 2-A and 2-B: Case 5L. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

4. Fig. 2-B: With full flexion of the elbow, the ulnar nerve and the medial head of the triceps are anterior to the medial epicondyle. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

5. Figs. 3-A through 3-F: Case 1L. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

6. Fig. 3-B With the elbow flexed about 45 degrees, the ulnar nerve has dislocated anterior to the medial epicondyle (indicated by the surgeon's thumb). ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

7. Fig. 3-C The medial head of the triceps does not end in a tendinous insertion; rather, muscle fibers extend more medially and insert onto the olecranon. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

8. Fig. 3-D A longitudinal incision was made in the raphe (indicated by the two forceps) between the normal triceps tendon and the prominent medial head of the triceps. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

9. Fig. 3-E A distinct accessory tendon was identified (indicated by the two forceps), which arose from a muscle belly deep to the medial head of the triceps tendon and inserted onto the proximal-medial portion of the olecranon. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.

10. Fig. 3-F The accessory triceps tendon and the medial head of the triceps have been redirected, and the decompressed ulnar nerve has been transposed anteriorly and stabilized within a fascial sling. ROBERT J. SPINNER, and RICHARD D. GOLDNER J Bone Joint Surg Am 1998;80:239-47 ©1998 by The Journal of Bone and Joint Surgery, Inc.