Background: Total hip replacement (THR) is an established procedure to relieve pain and restore function in advanced hip disease. Quantifying functional outcomes and identifying predictors of better or worse recovery helps refine patient selection, peri-operative care and rehabilitation.
Objective: To evaluate functional outcomes following primary total hip replacement and analyze factors associated with clinical improvement and complications.
Design: Prospective observational study.
Methods: 100 consecutive patients undergoing primary THR for osteoarthritis, avascular necrosis, or inflammatory arthritis were followed for 12 months. Outcomes were measured preoperatively and at 3, 6 and 12 months using the Harris Hip Score (HHS) and Oxford Hip Score (OHS). Secondary endpoints: complication rate, length of stay, time to independent ambulation, and patient satisfaction. Subgroup analyses examined age, BMI, diagnosis, surgical approach and comorbidity effects. Paired t-tests and multivariable linear regression were used; p < 0.05 considered significant.
Results: Mean age 64.1 ± 9.8 years; 58% female. Indications: primary OA 72%, AVN 18%, inflammatory arthritis 10%. Mean preoperative HHS = 41.6 ± 12.8; OHS = 19.8 ± 6.2. At 12 months mean HHS = 89.4 ± 8.6 (mean gain 47.8 points, p < 0.001); OHS = 42.1 ± 4.9 (gain 22.3 points, p < 0.001). 86% achieved “excellent/good” HHS (≥80). Median time to independent ambulation with aid = 3 days (IQR 2–4). Overall complication rate 8% (3 dislocations, 2 superficial wound infections, 2 DVTs, 1 periprosthetic fracture). On multivariable analysis, higher BMI (>30 kg/m²) and Charlson comorbidity index ≥3 were independently associated with smaller HHS improvement at 12 months (β −5.8, p = 0.02 and β −6.4, p = 0.01 respectively). Age, sex, diagnosis, and surgical approach were not significant predictors after adjustment. Patient satisfaction (Likert 1–5) at 12 months: 90% rated 4 or 5.
Conclusion: Primary THR produces large, clinically meaningful improvements in pain and function by 3 months that are sustained at 12 months. Obesity and multiple comorbidities predict reduced functional gains and should prompt optimized perioperative care and rehabilitation.