Effect of femoral offset on pain and function after total hip arthroplasty.

The effects of altering patients' femoral offset (FO) during total hip arthroplasty on postoperative pain and function have not been well described. This study compared clinical outcomes as assessed by the Short Form 12 Health Survey and Western Ontario and McMaster University Osteoarthritis Index between patients who had their FOs restored to varying degrees (compared to the contralateral normal hip [CL]). We retrospectively measured postoperative FOs on standard anteroposterior pelvis radiographs and compared to the CL. Patients were categorized into one of 3 groups: decreased offset (< -5 mm compared to CL), normal offset (between -5 and +5 mm), and increased offset (> +5 mm). The decreased offset group exhibited Western Ontario and McMaster University Osteoarthritis Index Physical Function scores that were less than those of the normal offset and increased offset groups (72.03, 82.23, and 79.51, respectively [P = .019]). In conclusion, reducing a patients' native FO led to inferior functional outcome scores.