This study reviews the incidence of polyethylene wear after total elbow arthroplasty. Nine hundred and nineteen total elbow replacements with a semiconstrained Coonrad-Morrey total elbow implant, which were performed between 1981 and 2000, were reviewed. Twelve patients (1.3%) had undergone an isolated exchange of the articular bushings as a result of polyethylene wear. Six additional patients were diagnosed as having bushing wear on the basis of an asymmetric anterior-posterior orientation of the ulnar component within the humeral yoke but these patients did not have a revision. All twelve patients that did undergo a revision had pain and five had crepitus during movement of the affected elbow. Patients with post-traumatic arthritis had a higher prevalence of busing wear (2.4%) than did those with rheumatoid arthritis (1.4%). The index primary total elbow arthroplasty in the twelve patients who underwent bushing exchange were performed when the patients were an average of 44 years old (range, 30 to 59 years). This compares with a mean age of 62 years in 907 patients who did not have isolated bushing exchange in the overall sample of 919 patients. Nine of the twelve patients had extensive or high-grade deformity or loss of at least one humeral condyle at the time of the primary total elbow arthroplasty. The period between the index arthroplasty and the bushing exchange averaged 7.9 years (range, 48 to 156 months). Radiographs prior to bushing exchange showed obvious asymmetry of greater than 10 degrees at the yoke. Osteolysis in the distal part of the humerus was identified in four patients and some resorption of the proximal part of the ulna was recorded in three. However, the osteolysis was not felt to be severe in any of these patients and there was no evidence of prosthesis loosening due to osteolysis.
The surgical technique included the use of the previous skin incision with ulnar nerve decompression only if there were persistent symptoms. The elbow joint was approached on either side of the triceps. If resorption due to osteolysis was noted, the interface was thoroughly cleaned and filled with methylmethacrylate. A soft-tissue release was performed if there was notable deformity. The mean duration of follow-up after the bushing exchange was 65 months. The mean arc of motion improved from 89 degrees before the surgery to 109 degrees after surgery. Eight patients reported no pain, one had mild pain, one had moderate pain and two had severe pain following revision surgery. The mean Mayo Elbow Performance Score was 86 points (range, 50 to 100 points) with eight elbows graded as excellent, one as good, one as fair and two as poor. Two patients had a poor result due to persistent pain from ulnar neuropathy following bushing exchange. Only one developed the neuropathy due to the revision surgery. Three patients underwent a second bushing exchange procedure because of clinical and radiographic evidence of wear of the previously exchanged bushing at 53, 54 and 136 months after the initial bushing exchange.
This retrospective review reveals a remarkably low rate of bushing exchange and osteolysis in 919 total elbow arthroplasties. However, the true incidence of bushing wear is difficult to determine from this article. In addition, there was no evidence of extensive osteolysis that is often seen in total hip and knee arthroplasties and is being reported elsewhere with this particular implant. The main correlation with bushing wear was younger post-traumatic patients with extensive preoperative deformity. Neither patient weight nor hand dominance appeared to be a predisposing factor to bushing wear. The authors recommend extensive soft-tissue releases of preoperative deformity to minimize the tension on the bushing. The authors recommend that if a patient has asymptomatic wear radiographically, they may simply be followed clinically and radiographically considering there is a low incidence of fixation-compromising osteolysis. The authors’ main indication for bushing replacement was pain or mechanical squeaking. Bushing exchange was found to be a successful procedure in most patients with low complications noted.
Journal of Bone and Joint Surgery