Functional outcomes after total hip arthroplasty in young patients: comparison of patients younger than 35 years versus patients aged 35–40 years

Background: Young patients undergoing total hip arthroplasty (THA) have high functional demands and expectations. This study compared postoperative functional outcomes between 2 age groups. Methods: In a prospective cohort study, the participants were divided into 2 groups: Group A consists of 35 patients aged under 35 years, while Group B contains 33 patients aged between 35 and 40 years. Dysplasia coxarthrosis was identified as the primary cause, with a prevalence of 55.9%. The primary outcome of this study was the functional outcome after THA, measured by the Hip disability and Osteoarthritis Outcome Score (HOOS). The Harris Hip Score (HHS), visual analogue scale (VAS) and Oxford Hip Score (OHS) were used as patient-related outcome measurements as a secondary aim. As well as the patient-related variables included underlying disease, sex, follow-up, and BMI. Results: The entire cohort consists of 68 hips in 54 participants with a mean follow-up duration of 58.74 ± 35.22 months, including 9 patients who underwent bilateral simultaneous THA. Significant improvements were observed in all HOOS subscales ( p < 0.05), with the total HOOS showing a mean increase of 41.66 ± 17.08 points from pre- to postoperative. Group B showed a significant greater improvement in the HOOS pain subscale and demonstrated superior outcomes in simultaneous bilateral THA. The HHS (Δ44.17 ± 14.03) and VAS pain score (mean decrease of 4,49 ± 2,63 points) also improved significantly ( p < 0.05). The postoperative HHS exceeded 90 points in both groups, with no observed baseline differences. No major complications were observed, with exception of 2 required revisions (<3%). Conclusions: THA in young patients resulted in improved functional outcomes and high levels of patient satisfaction. Postoperative outcomes were found to be comparable between patients aged <35 and those aged between 35 and 40 years. These findings indicate that THA can provide functional improvement in young patients, when underlying diseases, complex deformities and prior surgeries are considered.