Unique Case Study Post-traumatic Heterotopic Ossification Results In Ulnar Nerve Compression

Innovations in Orthopaedics | Spring 2025

Orthopaedic surgeons at University Hospitals Cleveland Medical Center published a case study in the Journal of Hand Surgery Global Online detailing their successful diagnosis and treatment of a previously undocumented presentation of ulnar nerve compression caused by heterotopic ossification in the hand.

Kevin Malone, MD

“Following a traumatic blow to the patient’s left hand, heterotopic bone formed and displaced the ulnar nerve,” says Kevin Malone, MD, Chief of the Division of Hand and Upper Extremity Surgery at University Hospitals. “Over time, the resulting nerve compression caused motor paralysis, muscle atrophy and progressive claw deformity.”

A Perplexing Case

In January 2023, an elementary school principal in his early 40s sustained a blunt-force injury to his hand while striving to de-escalate a disruptive student. Although the patient did not recall significant pain at the time, he began experiencing a progressive loss of sensation and movement in his fourth and fifth fingers.

Initial X-rays and physical examination did not reveal a clear diagnosis. As the gentleman’s impairment worsened, the declining function of his dominant hand significantly impacted his quality of life at home and in the workplace.

The patient experienced significant progression of symptoms over time. “About a month after injury, he returned for further evaluation,” Dr. Malone says. “An MRI of the affected fingers ruled out a pulley rupture, which is an injury to one of the restraining structures of the flexor tendons.”

On subsequent visits, the patient demonstrated partial pan paralysis. “Some of the muscles of the hand were not working properly, which explained the flexion deformity of the ring and small fingers,” Dr. Malone says.

An electromyography (EMG) test was obtained, revealing nerve injury. “The ulnar nerve has a sensation component responsible for feeling on the palm and dorsal side of the hand over the fourth and fifth fingers,” Dr. Malone says. “It also has a motor component, controlling the muscles that provide strength and dexterity of the hand.” The EMG showed an isolated injury consistent with weakness and lack of coordination.” The patient began occupational therapy to improve strength and function, but his symptoms did not substantially improve.

Surgical Management

Six months after injury, the patient’s search for answers led him to Dr. Malone’s hand surgery clinic. There, his case was presented to Dr. Malone by Kali Stevens, MD, a resident in the UH Orthopaedic Surgery Residency program. Her review of previous X-rays revealed heterotopic bone at the base of the little finger metacarpal. “The images showed a very subtle abnormality that led Dr. Stevens to conclude that this was the location of the patient’s ulnar nerve issue,” Dr. Malone says.

A CT scan confirmed the presence of abnormal bone formation near the deep motor branch of the ulnar nerve, raising the concern for posttraumatic compressive neuropathy. Two weeks later, Dr. Malone, assisted by Dr. Stevens, performed surgery to explore the ulnar nerve starting at the distal forearm. By tracing the nerve distally through its multiple branching patterns, Dr. Malone was able to mobilize it enough to get underneath and expose the abnormal bone growth. “Once the nerve was protected, we safely removed the bone, which allowed the nerve to fall back into normal position,” he says. “There is an unpredictable nature of nerve recovery; fortunately, we caught the compression in time and managed to avoid further damage to give this patient the best chance at recovery.”

A Remarkable Outcome

Post-surgery, the patient quickly resumed occupational therapy for range of motion exercises, intrinsic muscle strengthening and fabrication of an anti-claw orthosis. Despite his physical trials, he never gave up hope and persisted in completing his doctoral studies. Recently, he returned to reiterate his gratitude to Dr. Malone and the team at University Hospitals.

“His grip strength and dexterity are great—other than a scar on his hand, you would never know that he had this problem,” Dr. Malone says. “It has been a very uplifting, fulfilling experience to have this gentleman go out of his way to express his appreciation that we were able to restore the use of his hand.”

Dr. Malone is quick to point out the rarity of this injury, noting that neither he nor his colleagues nationwide had experienced anything similar. “This novel case highlights not only Dr. Malone’s widely recognized expertise as a fellowship-trained hand and microvascular surgeon but also the collaborative, patient-centered care that is fostered throughout our orthopaedics department,” says James Voos, MD, the Jack and Mary Herrick Distinguished Chair in Orthopaedics and Sports Medicine at University Hospitals, Executive Director of the UH Haslam Sports Innovation Center and a professor at the School of Medicine. “In addition to providing transformational care for this deserving patient, Dr. Malone and Dr. Stevens have contributed to the body of medical literature by documenting a previously unrecognized sequela of blunt hand trauma.”

For more information, contact Dr. Malone at Kevin.Malone@UHhospitals.org.

Contributing Experts:
Kevin Malone, MD
Chief, Division of Hand and Upper Extremity Surgery
Amy and Michael Southard Chair in Orthopedic Surgery
University Hospitals Cleveland Medical Center
Professor of Orthopaedic Surgery
Case Western Reserve University School of Medicine

James Voos, MD
Chair, Department of Orthopaedic Surgery
Executive Director
University Hospitals Haslam Sports Innovation Center
Jack and Mary Herrick Distinguished Chair, Orthopaedics and Sports Medicine
University Hospitals Cleveland Medical Center
Charles H. Herndon Professor
Case Western Reserve University School of Medicine
Head Team Physician, Cleveland Browns
Medical Director, Cleveland Ballet