# Association of osteotomy, age, and component fixation with the outcomes of total hip arthroplasty in patients with hip dysplasia: a Dutch population-based registry study

## TL;DR

This study found that younger age and prior pelvic osteotomies are linked to lower implant survival and worse outcomes in hip replacement surgery for hip dysplasia.

## Contribution

The study identifies age and prior osteotomies as key factors affecting hip replacement outcomes in hip dysplasia patients.

## Key findings

- 10-year revision-free implant survival was 94.9% for all patients.
- Patients younger than 50 had 93.3% 10-year survival, and those with prior osteotomy had 92.0%.
- Fixation method and sex did not affect implant survival, but prior osteotomy reduced PROM scores.

## Abstract

Hip dysplasia can present challenges for total hip arthroplasty (THA) due to anatomic abnormalities. We aimed to assess the association of age, sex, osteotomies prior to THA, and fixation method on 5- and 10-year revision-free implant survival and patient-reported outcome measures (PROMs) of THAs in patients with hip dysplasia.

Using Dutch Arthroplasty Register data, we studied hip dysplasia patients receiving primary THAs in 2007–2021 (n = 7,465). THAs were categorized by age, pelvic osteotomy prior to THA (yes/no), and fixation (cemented, uncemented, hybrid, reverse hybrid). Kaplan–Meier and multivariable Cox models were used to determine 5- and 10-year revision-free implant survival and adjusted hazard ratios including 95% confidence intervals (CIs). Reasons for revision and PROMs were compared within the categories.

We found a 10-year revision-free implant survival of 94.9% (CI 94.3–95.5). Patients younger than 50 years had a 10-year implant survival of 93.3% (CI 91.9–94.7), Patients with prior pelvic osteotomy had a 10-year implant survival of 92.0% (CI 89.8–94.2). Fixation method and sex were not associated with implant survival. Patients with a prior pelvic osteotomy had more revisions due to cup loosening and reported lower PROM scores than patients without earlier osteotomy.

5- and 10-year revision-free implant survival rates of THA for hip dysplasia are 96.4% and 94.9%. Age and prior osteotomies were associated with decreased implant survival rates in patients with hip dysplasia, while fixation method was not. Prior osteotomies were also associated with reduced PROM scores.