For Immediate Release
Oct. 25, 2025
AAHKS Clinical Research Award Study Seeks to Understand if Maximizing Bearing Diameter Markedly Lowers Dislocations in Primary Total Hip Arthroplasty
Oct. 25, 2025 (Dallas, TX) – At the 2025 American Association of Hip and Knee Surgeons (AAHKS) Annual Meeting, a paper seeking to understand if maximizing bearing diameter markedly lowers dislocations in primary total hip arthroplasty was awarded the AAHKS Clinical Research Award. This award is given annually in recognition of outstanding clinical research in the field of hip and knee arthroplasty.
In this study, led by Matthew S. Hepinstall, MD, and co-authors Eric Wang, BA, Theodor Di Pauli von Treuheim, MD, Catherine Di Gangi, BS, Ran Schwarzkopf, MD, MSc, Morteza Meftah, MD, all patients who underwent fixed-bearing THA at a large, urban, academic institution between 2016-2022 were reviewed. Cases were noted that received the largest bearing available from any manufacturer for the acetabular diameter. Larger cups were excluded, but multivariate analyses using least-absolute-shrinkage-and-selection-operator (LASSO) logistic regression were performed to explore the association between maximized bearing diameter and 90-day dislocation risk while controlling for confounders.
Results indicated that bearing diameter was maximized in 835 of 8,607 patients, whereas 7,309 received the second largest bearing available. There were 79 dislocations, however, none occurred with maximized bearing diameters. Dislocation risk also varied with intraoperative technology use, surgical approach and liner geometry. Sub-analysis of 4,185 patients with smaller bearings and posterior approach revealed that liner geometry did not impact dislocation odds within this sub-group, nor did receiving the second-largest available bearing demonstrably reduce dislocation odds compared to smaller bearings.
“For a surgeon looking to reduce their total hip arthroplasty dislocation rate, we found one to do tomorrow — without buying a new tool or learning a new approach. Utilizing the largest available bearing, within 14 millimeters of the cup diameter, associated with markedly reduced odds of dislocation. Advanced technology and stable surgical approaches mattered also, but bearing diameter had the largest effect size,” said Matthew S. Hepinstall, MD, senior author on the paper.
Abstract: AAHKS Clinical Research Award Abstract
About the American Association of Hip and Knee Surgeons
Established in 1991, the mission of AAHKS is to be the definitive global authority on excellence in hip and knee care. AAHKS has a membership of over 5,500 surgeons and other hip and knee health care professionals.
Contact:
Kenneth Robinson, Communications Manager
KRobinson@AAHKS.org
