A comparison of survivorship and functional outcomes for total elbow arthroplasty performed for distal humerus fracture, rheumatoid arthritis and osteoarthritis, a New Zealand Joint Registry Study.

Abstract

Common indications for total elbow arthroplasty include fracture, osteoarthritis, and rheumatoid arthritis. Total elbow arthroplasty is increasingly being performed for fracture in the context of an ageing population, improved medical management of rheumatoid arthritis, and improving surgical technologies. This study aimed to investigate survivorship of total elbow arthroplasty implants by indication using data from the New Zealand Joint Registry. Prospectively collected data from the New Zealand Joint Registry, a national database with capture >95%, were used to compare the survivorship rates and Oxford Scores of total elbow arthroplasty by indication for all procedures performed between January 2000 and December 2022. Underlying diagnoses, reason for revision and patient demographics were all recorded. Statistical analysis included survivorship analysis using Kaplan-Meier curves and comparison between groups using independent t tests. Over the 22 year study period, 601 total elbow arthroplasty procedures were performed representing 4875 component years. 185 total elbow arthroplasty procedures were performed for fracture, 318 for rheumatoid arthritis and 98 for osteoarthritis. The number of revisions per 100 component-years for total elbow arthroplasty was 0.40 for fracture, 0.98 for rheumatoid arthritis, and 1.86 for osteoarthritis. The adjusted revision rate for total elbow arthroplasty performed for fracture was lower than when performed for osteoarthritis (p=0.020) and equivalent to when performed for rheumatoid arthritis (p=0.240). Mean Oxford Scores 6 months post-operatively were 33.0 for total elbow arthroplasty procedures performed for fracture, 37.8 for total elbow arthroplasty performed for osteoarthritis and 39.0 for total elbow arthroplasty performed for rheumatoid arthritis. These differences were statistically significant (p<0.001). In the context of a higher proportion of total elbow arthroplasty being performed for complex distal humeral fractures and their post-traumatic sequelae, survivorship and functional outcomes appear to be favourable or comparable to traditional indications such as rheumatoid arthritis and osteoarthritis.