Hitting the Limb Length Target in Total Hip Arthroplasty Requires a Patient-specific Approach

Proper limb length restoration after primary total hip arthroplasty (THA) remains challenging. Current imaging and guidance tools do not account for patient-perceived or examination-based limb length differences. This study defined a three-pronged comprehensive approach to setting patient-specific limb length targets: 1) patient preoperative perception of limb length discrepancy (LLD), 2) surgeon objective examination of LLD, and 3) radiographic hip length measurements based on extent of cartilage and bone loss.

A total of 102 patients who had hip osteoarthritis undergoing primary direct anterior approach THA were included. Patient-perceived preoperative limb length was collected. Target hip length was then determined using a radiographic goal for lengthening, preoperative hip pathology, patient perception, and physical examination findings of LLD. The primary outcome was the presence of patient-perceived or surgeon-examined LLD at latest follow-up. Secondary outcomes included patient outcome scores.

A total of 102 patients (54.90% female) were included, with mean age and body mass index of 66.68 ± 11.79 years and 27.51 ± 4.63 kg/m², respectively. Preoperatively, 32.35% of patients reported perceived LLD. Postoperatively, 99.02% reported no LLD symptoms. Mean Hip Disability and Osteoarthritis Outcome Score, Joint Replacement scores improved from 49.41 ± 15.16 preoperatively to 79.34 ± 16.32 at 1 year.

Appropriate restoration of patient limb length remains an important target and a technical challenge. While different technologies can help surgeons achieve an LLD target, a three-pronged clinical approach to setting target LLD leads to over 99% patient satisfaction with their limb length at 1-year follow-up.