Failure patterns after linked semiconstrained total elbow arthroplasty for posttraumatic arthritis.

BACKGROUND

Total elbow arthroplasty for the treatment of posttraumatic arthritis is associated with a relatively high failure rate. An understanding of these failures can lead to improved implant design and surgical technique.

METHODS

Eighty-four consecutive patients underwent eighty-five semiconstrained total elbow arthroplasties for the treatment of posttraumatic arthritis. Sixty-nine elbows with a retained primary prosthesis were followed for an average of nine years. Clinical results were graded with use of the Mayo Elbow Performance Score. Radiographs were assessed for mechanical failure, and all complications were recorded.

RESULTS

Sixteen primary arthroplasties (19%) failed. Causes of failure included isolated bushing wear (seven), infection (four), component fracture (three), and component loosening (two). The most common cause of early failure (failure after less than five years) was infection, whereas intermediate-term failure (failure after five to ten years) typically was due to bushing wear. Late failure (failure after more than ten years) was uncommon and involved component loosening or fracture. Seventy-five percent of the failures were in patients who were less than sixty years old at the time of surgery (p = 0.03). Progressive radiolucent lines were noted around four implants, three of which had clinically important loosening. Total elbow arthroplasty was associated with significant improvements in terms of pain, motion, and the Mayo Elbow Performance Scores (p < or = 0.002). Sixty-eight percent of the patients achieved a good or excellent clinical result, and 74% were subjectively satisfied. Kaplan-Meier analysis demonstrated a fifteen-year survival rate of 70% with revision or resection for any reason as the end point.

CONCLUSIONS

Semiconstrained total elbow arthroplasty in patients with posttraumatic arthritis places high demands on the implant and is associated with a relatively high failure rate. Seventy-five percent of failures occur in patients less than sixty years of age, and infection continues to represent a frequent mode of early failure. Bushing wear and component loosening or fracture are seen more commonly in the intermediate and late term, whereas aseptic loosening remains relatively uncommon.