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Updated: Jun 8, 2026
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Three-Dimensional Preoperative Virtual Planning in Derotational Proximal Femoral Osteotomy
Published on: February 17, 2023
Stem torsion in total hip replacement
Ernst Sendtner1, Schuster Tibor, Roman Winkler
1Department of Orthopedic Surgery, Regensburg University Medical Center, Regensburg, Germany. ernst.sendtner@web.de
Acta Orthopaedica
|October 6, 2010
Summary
Accurate femoral torsion in total hip replacement (THR) is crucial for optimal outcomes. This study found significant variability and gender differences in postoperative stem antetorsion, highlighting the need for intraoperative assessment.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Radiology
Background:
- Correct femoral torsion is essential for improving clinical outcomes in total hip replacement (THR).
- Postoperative evaluation of femoral stem position is critical for assessing surgical accuracy.
- Variations in femoral torsion can impact joint biomechanics and implant longevity.
Purpose of the Study:
- To evaluate the position and torsion of the femoral stem after minimally invasive total hip arthroplasty (THR).
- To assess the prevalence of abnormal stem antetorsion in a cohort of patients undergoing THR.
- To investigate potential gender-related differences in femoral stem antetorsion.
Main Methods:
- Prospective enrollment of 60 patients undergoing total hip arthroplasty.
- Minimally invasive THR performed via an anterior approach in the lateral decubitus position.
- Postoperative computed tomography (CT) examination to evaluate stem position by an independent institution.
Main Results:
- Femoral stem torsion exhibited a wide range, from -19° retrotorsion to 33° antetorsion.
- Abnormal stem antetorsion (outside 10–15° Tönnis range) was observed in 92% of patients.
- A significant gender difference was noted, with women exhibiting higher mean stem antetorsion (8.0°) than men (1.5°).
Conclusions:
- Postoperative stem antetorsion demonstrates high variability and is influenced by gender.
- Intraoperative assessment of stem antetorsion, potentially using computer navigation, is recommended.
- Strategies for managing abnormal stem antetorsion include adjusting cup position, using modular components, or employing stems with specific neck designs.
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