Review Question - QID 216807

This patient has bushing wear which is the most common mode of failure in semi-constrained total elbow arthroplasty (TEA) design at midterm follow-up, particularly when TEA is initially performed for post-traumatic arthritis.

There are various indications for TEA including rheumatoid arthritis, primary osteoarthritis, post-traumatic arthritis, fracture, and chronic instability. The three basic designs include unconstrained, semi-constrained, and constrained. Semi-constrained designs have the best longevity and functional outcomes. Despite their reliable outcomes, complications can occur in up to 25% of cases. Bushing wear is the most common mode of failure in semi-constrained designs at intermediate follow-up, particularly in the post-traumatic setting. Several potential factors have been proposed for the increased risk of bushing wear in the post-traumatic setting including younger patients and lack of adherence to postoperative restrictions, an unstable traumatic injury, excessive preoperative deformity, and soft-tissue contractures, all of which could place abnormal forces on the bushing component.

Throckmorton et al. reviewed 84 consecutive patients who underwent 85 semi-constrained TEA for the treatment of posttraumatic arthritis with an average follow-up of 9 years. Of 69 TEA included for analysis, 19% (n=16) failed. Early failure (<5 years) was most commonly due to infection. Intermediate-term failure (5-10 years) was most commonly due to bushing wear. Finally, late failure (> 10 years) was most likely to occur due to loosening or fracture.

Morrey et al. provide a review of TEA for posttraumatic arthritis. Although it can be an effective treatment option, about 25% will experience complications. The rate of aseptic loosening is less than 10% after 10 years. Prosthetic fracture is the most common cause of late failure. Infection is the most common mode of early failure. Bushing wear is the most common cause of mechanical TEA failure at intermediate-term follow-up.

Schneeberger et al. reviewed 41 consecutive patients who underwent semi-constrained TEA for posttraumatic arthrosis. The average follow-up was 5 years (2-12 years). A good to excellent outcome was seen in 83%. Meanwhile, 27% had a major complication and 22% underwent re-operation.

Figure A is an AP radiograph of an elbow status post TEA demonstrating valgus angulation of >10 deg which is concerning for bushing wear. Illustration A is an AP radiograph of a normal semi-contrained TEA to serve as a comparison with Figure A.

Incorrect Answers:
Answer 1: Gender is not directly associated with bushing wear
Answer 2: History of smoking has not been linked to bushing wear
Answer 4: The use of cement is not associated with bushing wear
Answer 5: Age has not been linked to bushing wear