RESUMO
BACKGROUND: Accurate restoration of leg length and proximal femoral geometry is essential for achieving satisfactory outcomes in both primary and revision total hip arthroplasty. Although common landmarks such as the greater trochanter and the lesser trochanter (LT) may be used to measure limb length intraoperatively in primary cases, these landmarks may be absent or disrupted in fractures and revision procedures. We propose the distance between the gluteus maximus tendon gluteal sling (GS) and the center of the femoral head (FHC) as a novel anatomic landmark beyond the zone of injury, which can be used to restore limb length in the setting of proximal femoral bone loss or fracture. METHODS: One hundred healthy hips were retrospectively reviewed using MRI to determine the distance between the proximal edge of the GS and the FHC. Additional measurements were collected including the distance between the GS and the greater trochanter and LT, as well as the FHC to the LT and greater trochanter.Results: The distance between the GS and the femoral head was consistent and measured 8.0 cm (±1.88 cm, SD = 0.66). A moderate positive correlation (r = 0.37, P < 0.001) was observed between patient height and GS to FHC distance. DISCUSSION: The distance between the GS and the center of the femoral head consistently measures 8 cm and can be used to set implant height to restore proximal femoral geometry and leg length in total hip arthroplasty with proximal femoral bone loss.
