Hmmm…Implant Selection Doesn’t Affect THA Outcomes

Choice of implant doesn’t affect patient-reported outcome measures after primary total hip arthroplasty, according to a new study.

In the study, “Does Implant Selection Affect Patient-Reported Outcome Measures After Primary Total Hip Arthroplasty,” the researchers analyzed data on 4,716 patients who had underwent primary total hip arthroplasty between July 2015 and August 2018 at a single health-care system.

The findings were published on December 15, 2021 in The Journal of Bone and Joint Surgery.

They wrote, “Total hip arthroplasty is a reliable operation, but it is critical that orthopedic surgeons characterize which surgical factors influence patient-reported outcomes.”

Researchers focused their analysis on whether implant selection affected the odds of having inadequate improvement in pain, function and activity, and having failure to achieve a substantial clinical benefit with respect to pain as well as failure to achieve a Patient-Acceptable Symptomatic State according to pain and function.

All the patients were categorized by the type of femoral and acetabular components and bearing surface used.

Overall, one-year postoperative patient-reported outcome measures were available for 3,519 patients.

There were no differences in the proportion of patients who attained the Minimal Clinically Important Difference for the Hip disability and Osteoarthritis Outcome Score pain and physical function short form or the University of California at Los Angeles activity score at 1 year.

According to multivariate regression, implant selection was not a significant driver of inadequate improvement.

Larger 36-mm femoral heads compared with 28-mm femoral heads were associated with lower odds of inadequate improvement, according to the University of California at Los Angeles activity scores (OR: 0.64; 95% CI, 0.47 to 0.86; p = 0.003).

In addition, implant-related criteria were not significant drivers of attaining a Patient-Acceptable Symptomatic State or achieving a substantial clinical benefit with respect to Hip disability and Osteoarthritis Outcome Score pain.

“For the most part, total hip arthroplasty implant characteristics are not drivers of inadequate improvement with respect to pain and function. Surgeons should utilize implants with an acceptable track record that allow stable fixation and restoration of hip biomechanics,” the researchers wrote.

Study authors include Andrew Campbell, M.D., Ahmed K. Emara, M.D., Alison Klika, M.S., Nicolas S. Piuzzi, M.D., all of The Cleveland Clinic, and The Cleveland Clinic OME Arthroplasty Group.