Femoral Anteversion Alterations Linked to Ischiofemoral Impingement Post-THA
Overview
This retrospective CT study evaluated the impact of femoral anteversion (FA) and femoral offset (FO) changes on ischiofemoral impingement (IFI) and greater trochanteric pain syndrome (GTPS) after anterior-approach total hip arthroplasty (THA). Findings suggest increased FA is associated with IFI, while FO changes showed limited correlation with GTPS.
Background
Total hip arthroplasty (THA) is increasingly common due to rising life expectancy, generally providing pain relief and functional restoration. However, some patients experience persistent or new hip pain postoperatively, with causes including aseptic loosening, instability, and soft tissue impingements. Greater trochanteric pain syndrome (GTPS) and ischiofemoral impingement (IFI) are recognized sources of lateral and buttock/groin pain after THA. The role of femoral anteversion and offset changes in these pain syndromes, particularly following anterior surgical approaches, remains underexplored.
Data Highlights
Parameter
Measurement Method
Clinical Correlation
Femoral Anteversion (FA)
Angle between femoral neck base center and prosthesis head center vs. posterior tangent of femoral condyles on CT (Murphy et al method)
Higher FA associated with increased IFI incidence
Femoral Offset (FO)
Measured on CT pre- and post-surgery
Limited and conflicting association with GTPS
Ischiofemoral Space
Measured on postoperative CT images
Reduced space correlates with IFI signs (edema/fatty atrophy of quadratus femoris)
Key Findings
Increased femoral anteversion after anterior-approach THA is linked to a higher occurrence of ischiofemoral impingement.
IFI diagnosis was supported by clinical examination and imaging evidence of quadratus femoris muscle edema or fatty atrophy.
GTPS diagnosis relied on clinical symptoms and imaging signs of abductor tendinopathy or trochanteric bursitis.
CT imaging is a valuable tool for assessing component positioning and soft tissue impingement post-THA.
Clinical Implications
Clinicians should consider evaluating femoral anteversion changes when patients present with buttock or groin pain after anterior-approach THA, as increased FA may predispose to ischiofemoral impingement. Accurate CT measurement of FA and ischiofemoral space can aid diagnosis and guide management. Awareness of limited FO impact on GTPS may help focus diagnostic efforts on other etiologies.
Conclusion
Alterations in femoral anteversion following anterior-approach THA are associated with ischiofemoral impingement, contributing to postoperative hip pain. CT-based assessment of FA and related soft tissue changes is essential for accurate diagnosis and targeted treatment.
References
Author/Source/Year -- Alterations in Femoral Anteversion Linked to Ischiofemoral Impingement Following Total Hip Arthroplasty: A Retrospective CT Analysis
Systematic review found robotic-assisted total hip arthroplasty improved implant positioning precision without demonstrating better patient-reported outcomes or lower complication rates than conventional surgery.
