Leg length inequality after total hip arthroplasty.

Leg length inequality (LLI) in 55 patients with cemented total hip arthroplasty (THA) was measured from weight-bearing anteroposterior (AP) hip radiographs. The mean radiologic LLI was 8.7 mm in unilateral and 11.6 mm in bilateral THA, differing significantly from the clinically measured values (2.8 mm and 4.2 mm, respectively). LLI as a cause of aseptic loosening and unexplained pain warrants investigation in THA patients.