Authors: Vasarhelyi EM, Howard JL, Naudie DD, McCalden R, MacDonald SJ.
University of Western Ontario, London, ON, Canada
Title: Two-Stage Revision Total Knee Arthroplasty with an Articulating Spacer: Minimum Five-Year Review
Background: Total knee arthroplasty is a successful procedure, but has a risk of periprosthetic joint infection of 1-2%. The current gold standard of treatment for chronic infection is a two-stage revision arthroplasty.
Hypothesis/Purpose: To review the minimum 5-year results of two-stage revision total knee arthroplasty with articulating spacers for chronically infected total knee arthroplasty, and to compare these outcomes with non-articulating spacers.
Methods: A total of 106 patients with an infected total knee arthroplasty deemed most appropriately treated with a two-stage revision arthroplasty were prospectively enrolled. Patients were retrospectively reviewed based on the type of spacer used during their first-stage revision; 60 patients were treated with articulating spacers, while 46 were treated with non-articulating spacers.
Prospective data was collected including demographic information, KSS, WOMAC and SF-12 scores. The scores were obtained prior to revision surgery and annually during their standard follow up clinical review. In addition, need for subsequent surgery was collected.
Results: There were statistically significant improvements in all components of the KSS (p <0.001), WOMAC pain (p=0.02), stiffness (p=0.05) and function (p=0.001) when comparing post-operative to pre-operative scores. Survivorship of revision total knee arthroplasty that were initially treated with articulating spacers at 5 years for all causes and aseptic loosening was 88.1% and 91.3% respectively.
When comparing articulating and static spacers, knees treated with articulating spacers obtained an average range of motion of 100 degrees in comparison to 84 degrees for the static spacers (p=0.009).
Discussion: Infected TKA is a challenging problem to treat. The use of articulating spacers has become the standard of care for a two-stage revision. The use of articulating spacers resulted in similar rates of eradication to static spacers while yielding a clinical and statistical improvement in post-operative range of motion.
Conclusion: Two-stage revision for an infected total knee arthroplasty with an articulating spacer resulted in successful eradication of infection in 91.3% of patients at five years. There was a clinically significant improvement in post-operative range of motion when compared to revisions performed with a static antibiotic spacer.