Managing Prosthetic Fractures of the Elbow

Elbow replacements called elbow arthroplasties are used most often for patients with rheumatoid arthritis, fractures that don't heal, and for elbow problems after trauma or injury. In a small number of cases, the implant, also called a prosthesis, can fracture.

In this study, doctors from the Mayo Clinic report on the results of treatment for 23 elbow implants that fractured. Two-thirds of the patients had a fractured ulnar component. One-third had a broken humeral component. The ulna is the larger of two bones in the forearm. The humerus is the upper arm bone. The stem of the elbow implant fits down into each of these bones to anchor it in place.

Two methods were used to repair the broken prosthetic. In some cases, the implant was cemented back together. This is called a cement-within-cement technique. Other patients were treated by removing the cement and replacing the broken piece.

Results were measured in terms of pain relief and function. X-rays were used to look for bone loss and placement of the implant. Everyone was followed for an average of five years after revision for the fracture. There was a wide range of outcomes from excellent to poor.

Infection, bone loss, and cancer metastases were factors for patients with poor results. Two other patients had ongoing moderate pain with no known cause. Problems after the revision operation were common. These included nerve damage, tendon avulsion, elbow stiffness, bone fracture, and loosening of the prosthetic.

The authors conclude that fatigue fracture from high stress is the most likely cause of elbow prosthetics. Some of these problems have been corrected with a new implant that came out in the year 2000. There have been no reported ulnar fractures since then. Revision techniques and ways to avoid fatigue fractures are included in this study for surgeons treating patients with elbow arthroplasties.

References: George S. Athwal, MD, FRCSC, and Bernard F. Morrey, MD. Revision Total Elbow Arthroplasty for Prosthetic Fractures. In The Journal of Bone and Joint Surgery. September 2006. Vol. 88-A. No. 9. Pp. 2017-2026.