5,153 Patient THA Study Finds 2.8x Revision Racial Disparity

Kudos to both the research teams and the American Joint Replacement Registry (AJRR). Due in some measure to the law of large numbers, in this case more than 5,000 total hip arthroplasties in young (18-55 years of age), a research team was able to find clear pattern of racial disparity in terms of hip arthroplasty (THA) outcomes.

This new, important study by a research team from New York University Langone Orthopedic Hospital titled: “Trends in Complications and Outcomes in Patients Aged 65 and Younger Undergoing Total Hip Arthroplasty: Data from the American Joint Replacement Registry,” is published in the Journal of the American Academy of Orthopaedic Surgeons Global Research Review.

“The demand for total hip replacements is expected to increase 174% from 2005 to 2030, and 28% of the 572,000 THA procedures performed annually are in patients under the age of 55,” said lead author David Cieremans, M.S., a medical student at Philadelphia College of Osteopathic Medicine.

“When a young and active patient is exploring THA, it’s important for their surgeon to understand the expected life span of the implant to help make informed decisions. The AJRR [American Joint Replacement Registry] provided an incredible resource for our team to obtain robust data on hip replacements, along with a standardized metric to analyze surgical trends and patient outcomes from around the country.”

Working with all THAs performed from 2012 through 2020 in patients aged 18 to 65, the researchers looked at cumulative revision rate, 90-day readmission rate and reason for revision. In total, data from 5,153 patients was analyzed (51% female and 49% male) with an average age of 56.7 years ± 7.8 years. The mean follow up was 39.57 months.

The summary results of the study were:

• Fifty-three patients (1%) underwent revision during the study period, and 74 patients (1.4%) were readmitted within 90 days.
• The most common causes for revision were infection (20.8%), instability (15.1%), periprosthetic fracture (13.2%) and aseptic loosening (9.4%).
• The most common reasons for 90-day readmission without revision were infection (22.9%), pain (9.5%) and periprosthetic fracture (5.4%).
• The researchers found racial disparities in revision rates, as readmission within 90 days requiring revision were 2.76 times more common in Black patients compared to white patients.

“This is an important finding, and more long-term outcome studies are needed to understand why Black patients are being disproportionately affected,” said senior author Ran Schwarzkopf, M.D., M.Sc., professor of orthopedics at NYU Langone Orthopedic Hospital.

“Other research has concluded that Black patients are 30% less likely to undergo an elective total hip replacement than white patients, and patients from lower socioeconomic backgrounds experience higher baseline scores for pain and function. Given the advances in THA and favorable outcomes for patients under the age of 65, the orthopaedic community needs to work to improve patient outcomes for all patients.”

When OTW asked Dr. Schwarzkopf why Black patients might be more affected and if they are less affected than 10 years ago, he commented, “We do not have data in the American Joint Replacement Registry to compare revision risk after THA as it is limited to its start date as a registry. Furthermore, I do not have a good hypothesis why we are seeing this trend in young Black patients undergoing THA. We do know that low socioeconomic status can lead to higher revision rates, but we did not have the data to evaluate this link in the American Joint Replacement Registry data set.”

As for further work in this area, he added, “Currently at NYU we are working on different projects evaluating both disparities in care and in outcome. Some of the work we are doing is evaluating both disparities in patients’ follow up over time after TJA [total joint arthroplasty].”