A 58-year-old female presented at our outpatient clinic with pain and limited range of motion of her left elbow. She had been diagnosed with medial epicondylitis with possible coincidental ulnar neuritis and had undergone medial epicondylectomy and debridement of the common flexor tendon origin of the symptomatic elbow, at another institution seven months prior to visiting to our clinic. Upon initial presentation, the patient's range of motion was limited to 135° flexion and 45° extension on the left elbow, compared to 150° flexion and 0° extension on the right side. Supination and pronation were not limited on either side. The patient complained of persistent pain at the medial aspect of the elbow and a tingling sense of her small finger. A review of her outside initial preoperative radiographs revealed only mild calcification at the medial epicondyle (Fig. 1). Immediate postoperative radiographs did not show any abnormal findings (Fig. 2). At the time of her visit to our clinic, seven months after the operation, radiographs revealed prominent heterotopic ossification of the elbow (Fig. 3). Computed tomography scans further revealed heterotopic ossification at the medial epicondyle, trochlea, posterior portion of the capitellum and olecranon (Fig. 4).

We performed surgery to remove heterotopic bone and relieve ankylosis. A posteromedial incision was made along the left elbow. The ulnar nerve was found to be entrapped within the heterotopic bone. Beginning from the medial supracondylar ridge, the posterior and anterior muscles were elevated, exposing the heterotopic bone. The heterotopic bone attached to the medial side of the olecranon was found to be blocking the elbow from full extension. We identified the ulnohumeral joint and carefully osteotomized and removed the heterotopic bone from the olecranon, and also removed the heterotopic bone on the posteromedial side of the medial epicondyle. After gentle manual arthrolysis, we achieved full range-of-motion at the elbow from 145° flexion to 10° hyperextension. Rotation of the forearm was full. Then we performed subcutaneous anterior transposition of the ulnar nerve.

After surgery, the patient was encouraged to perform gentle elbow range-of-motion exercises a few days postoperatively. Postoperative radiation therapy was not performed. Non-steroidal anti-inflammatory drugs were prescribed for heterotopic ossification prophylaxis. One year postoperatively, elbow range of motion was full with no evidence of heterotopic ossification on follow-up radiographs (Fig. 5).

A 48-year-old male visited with limited range of motion of his right elbow. He had been diagnosed with cubital tunnel syndrome and had undergone cubital tunnel release and medial epicondylectomy at another institution one year prior to visiting to our clinic. The patient's range of motion was limited to 90° flexion and 0° extension, compared to 135° flexion and 0° extension on the left side. Supination and pronation were not limited on either side. His symptoms of ulnar nerve compression had improved, but the range of motion began to decrease postoperatively. His outside initial preoperative radiographs showed mild calcification at the medial epicondyle (Fig. 6). At the time we saw the patient, radiographs revealed heterotopic ossification at the medial and posterior sides of the elbow (Fig. 7). We considered that the heterotopic bone formed at the posterior oblique bundle of the medial collateral ligament was causing limitation of the elbow flexion. Although we recommended heterotopic bone removal and contracture release, the patient declined further operative treatment.