Computational prediction of the impact of scapular notching and real contact area on wear in reverse total shoulder arthroplasty compared to in-vitro results

Wear behavior of reverse total shoulder arthroplasty (RTSA) implants is typically assessed through in-vitro wear testing, which is time-consuming and expensive, and few in-vitro wear tests consider the impact of scapular notching on articular wear rates. This work presents a computational model of wear in RTSA and applies it to predict articular wear rates on implants with progressive simulated scapular notches. The computational model found a decrease in wear rates of between 6.3% and 24% after the introduction of scapular notching, which is comparable with decreases found by in-vitro tests in the literature.