This study was a retrospective review of 24 patients with 27 fractured total elbow arthroplasty components treated over a 24-year period at the Mayo Clinic. There were 17 ulnar component fractures and 10 humeral component fractures. There were 16 women and 8 men with an average age of 64 years (range, 32 to 86 years) at the time of revision surgery. The mean age of the patients at the time of primary elbow arthroplasty was 55 years (range, 23 to 78 years). An average of 4 prior procedures and 1.6 prior arthroplasties had been performed on the affected elbows prior to the revision because of the component fracture. The average time between the insertion of the implant and the revision surgery due to the implant fracture was 8.2 years (range, 2.4 to 13.8 years) for the humeral component and 4.6 years (range, 1.1 to 11 years) for the ulnar component.
All component fractures occurred in a portion of the stem adjacent to the linkage or articular apparatus where the implant was unprotected by host bone. In 25 of the 26 revisions, the remaining implant that was unfractured was found to be stable. In 14 cases, the fractured component was removed and a new component was cemented into an intact, expanded cement mantle, a technique referred to as "cement-within-cement" or "tap-out-tap-in." This technique was utilized when preoperative radiographs demonstrated an intact cement mantle with preservation of the cement-bone interface. A more traditional approach was utilized in the remaining 12 revisions by cementing into a reamed, cement free, prepared medullary cavity with or without strut allograft augmentation. Overall, there was a 1.2% prevalence of ulnar component fracture following primary total elbow arthroplasty and a 0.65% rate of humeral component fracture following primary total elbow arthroplasty. The rates of ulnar and humeral component fracture were 1.8% and 1% respectively following primary total elbow arthroplasty performed for the sequelae of trauma and 0.9% and 0% following those performed for rheumatoid arthritis. There was a 2.6% component fracture rate following revision arthroplasty. At a mean of 5.1 years following revision for these fractures, the Mayo Elbow Performance Score averaged 79 points (range, 50 to 100 points) and was excellent for 8 patients, good for 5, fair for 6 and poor for 2. Eight patients had no pain in the elbow, 7 had mild pain and 6 had moderate pain. The average final arc of motion was 108° (range, 70 to 145°), with flexion averaging 131° and extension averaging 23°. Complications included 7 intraoperative cortical perforations, 5 nerve injuries including 2 that were permanent, 3 triceps avulsions and 1 deep infection.
This study identified a low prevalence of total elbow prosthetic fractures. However, the incidence was increased in revisions, total elbows placed for traumatic reconstruction and noncompliant patients regarding weight limitations on the extremity. In addition, most of the component fractures occurred in patients with deficient bone at the time of index arthroplasty. In addition, this paper introduced the concept of a cement-within-cement technique for revision arthroplasties with a stable cement mantle. Operative times were diminished on average by 45 minutes over conventional techniques with similar outcomes. There was a high complication rate but was similar for both techniques.
Elbow, Arthroplasty, Revision, Fracture
J Bone and Joint Surg