JBJS Editor’s Choice: Volume-Outcome Relationships in Arthroplasty

Whenever the impact of surgeon volume on patient outcomes for technically complex interventions has been assessed, the following correlation has held: the higher the surgeon volume, the better the patient outcomes. Working with us at the University of Washington in 1997, Dr. Hans Kreder was one of the first to observe this relationship in joint replacement surgery.¹ Patients whose hip replacement was performed by a “high-volume” surgeon (>10 hip replacements per year) were significantly less likely to die or have an infection or revision than those whose procedure was performed by a “low-volume” surgeon (<2 hip replacements per year). This makes perfect intuitive sense—the more you do something, the better your skill, and the better the result.

In the study by Liddle et al. in the January 6, 2016 JBJS, the same volume-outcome relationship for knee arthroplasty is confirmed. The relationship is stronger for unicompartmental arthroplasty than it is for total knee arthroplasty (TKA). Again this makes intuitive sense because the “uni” procedure is more dependent on nuanced bone cuts and component placement than TKA, which relies more heavily on the use of guides and jigs.

Does this mean that the end of general orthopaedic surgeons performing joint replacement is at hand? I don’t think so. Many patients will prefer to stay in their community rather than travel to the high-volume surgeon/hospital even after being informed of the volume-outcome relationship. Additionally, joint registries and routine measurement tools now exist that can help lower-volume surgeons monitor their patient outcomes and demonstrate that their results are similar to those of higher-volume surgeons.

Ultimately, all surgeons are responsible for assessing their individual patient outcomes and making that data available for patients who are considering joint arthroplasty.

Marc Swiontkowski, MD

JBJS Editor-in-Chief

Reference

1. Kreder HJ, Deyo RA, Koepsell T, Swiontkowski MF, Kreuter W. Relationship between the volume of total hip replacements performed by providers and the rates of postoperative complications in the state of Washington. J Bone Joint Surg [Am] 1997;79(4):485-94.