Hip shape may predict total hip replacement
TORONTO — Hip shape parameters such as decreasing acetabular coverage were among factors that predicted total hip replacement in a cohort of individuals from Australia, according to findings presented here.
Laura L. Laslet, PhD, of the University of Tasmania in Hobart, Australia, and colleagues, looked at 1,100 participants aged 50 to 80 years from the Tasmanian Older Adult Cohort (TASOAC) Study. “Hip pain and radiographic hip osteoarthritis are very specific predictors of total hip replacement,” she said. “But they are not the only predictors. We know that aspects of hip shape predict aspects of hip replacement.”
Conventional factors that underwent analysis included pelvis X-rays, radiographic hip OA, WOMAC hip pain, and bone density. MRI data provided information on bone marrow lesions and hip effusion or synovitis. Other hip shape parameters included CAM impingement and femoral head shape. The researchers used statistical shape modeling to identify the hip shape parameters. “This is a technology that has been developed by our collaborators at the University of Aberdeen,” Laslet said.
Decreasing acetabular coverage was described as shape mode 2, and aspherical femoral head was described as shape mode 4.
Laslet highlighted that no study has looked at all of these potential predictors in the same data set. “The aim of this study was to identify risk factors that predict total hip replacement independent of hip and hip osteoarthritis in community-dwelling older adults,” she said.
The study duration was from 2002 through 2016.
Laslet reported results for 40 patients who underwent hip replacements and 762 who did not. “Comparisons between those who did and those who did not showed no differences in terms of age, sex, or BMI,” Laslet said.
Other risk factors for total hip replacement included WOMAC hip pain (P < .001), bone marrow lesions (P < .03), radiographic OA (P = .001), CAM impingements (P < .001), shape mode 2 (P = .01), and shape mode 4 (P = .016).
Hip radiographic OA and pain scores more than WOMAC 4 were associated with an almost 30% cumulative risk over 15 years, according to Laslet.
“Combination of measures may allow us to improve models predicting risk of total hip replacement,” Laslet concluded. “All of these things can only help us in finding ways to prevent and treat osteoarthritis. We have shown in our data that age, sex, and BMI did not predict total hip replacement independent of pain and hip osteoarthritis.” – by Rob Volansky
Mezhov V, et al. Abstract 78. Presented at: OARSI 2019 World Congress on Osteoarthritis; May 2-5; Toronto.
Disclosure: Laslet reports no relevant financial disclosures.