Patient-Reported Outcomes in Young Adults with Osteonecrosis Secondary to Developmental Dysplasia of the Hip
Abstract Background Osteonecrosis of the femoral epiphysis is a common complication in the treatment of developmental dysplasia of the hip (DDH). While functional outcomes of affected patients are good in childhood, it is not clear how they change during the transition to young adulthood. This study looks at determining the relationship between osteonecrosis of the femoral head and hip function, physical function and health status in adolescents and young adults treated for DDH.Methods We included 149 patients with a mean (and standard deviation) age of 19.7 (3.8) years with osteonecrosis following an open or closed reduction (1995–2005) and 32 age-matched patients without osteonecrosis. All patients completed valid and reliable patient-reported outcome measures in 2015/16 to quantify their hip function (maximum score 100); physical function (maximum score 100); and general health status (maximum score 1). We graded all radiographs for severity of osteonecrosis (Bucholz-Ogden); acetabular dysplasia (centre-edge angle); subluxation (Shenton’s line); and osteoarthritis (Kellgren-Lawrence). We determined the association between the patient-reported outcomes and radiographic severity of osteonecrosis using mixed-effects regression analysis adjusted for age and acetabular dysplasia at study assessment, and number of prior operations.Results In 149 patients (186 hips) with and without osteonecrosis, the mean differences (95% confidence interval) in hip function, physical function and quality of life were − 4.7 (-10.26, 0.81), -1.03 (-9.29, 7.23) and 0.10 (-1.15, 1.18), respectively. Adjusted analysis stratified across radiographic severity of osteonecrosis showed only patients with Bucholz grade III had significantly worse hip function (p < 0.01) and physical function (p < 0.05) but no difference in health-related quality of life when compared to no osteonecrosis.Conclusion Osteonecrosis secondary to DDH is a relatively benign disorder in young adulthood. Affected patients demonstrated minimal physical disability, a normal quality of life but reduced hip function.