CORR Insights®: High Risk of Neck-liner Impingement and Notching Observed with Thick Femoral Neck Implants in Ceramic-on-ceramic THA

Since Charnley’s first THA in 1962, implant surveillance has been the mainstay of quality-improvement efforts, to the great benefit of patients. Such surveillance can be conducted using large registries and other “big data” sources. But single-center, local-database studies continue to play a very important role as well. Although sample sizes in these studies are smaller, they generally have more complete information on patient factors, the surgery itself, implant sizes, and radiographic findings than do insurance databases or national registries. Such findings become even more meaningful when they are replicated by others.

In a study published in this month’s Clinical Orthopaedics and Related Research®, Kim and colleagues [⁴] detail how good-quality single-center implant surveillance can result in actionable recommendations. In this report, the authors confirmed previously reported findings of radiographically evident stem-liner impingement and notching in a particular implant system. In addition, they reported a concerning frequency of ceramic bearing fracture and squeaking in this cohort. Notably, implant position was not found to be associated with these worrisome findings, suggesting that the design of the implant itself, namely a thick femoral neck, is of primary concern. The authors have subsequently abandoned the use of this implant and urge other surgeons to do the same. Based on the results of their study, I agree with their recommendation.