A Useful Anatomical Reference Guide for Stem Anteversion during Total Hip Arthroplasty in the Dysplastic Hip

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiology

Background:

• Developmental dysplasia of the hip (DDH) presents challenges in total hip arthroplasty (THA).
• Accurate femoral stem anteversion is crucial for optimal THA outcomes.
• The T line offers a potential reference for stem positioning in dysplastic hips.

Purpose of the Study:

• To evaluate the compatibility of T line-based femoral stem anteversion with native femoral anteversion in DDH.
• To assess the impact of simulated cutting heights on anteversion measurements.

Main Methods:

• Computed tomography (CT) scans of 50 dysplastic hips were analyzed.
• Preoperative planning software was used for THA simulation.
• Femoral stem anteversion was measured using the T line at 5mm and 10mm cutting heights.

Main Results:

• The mean difference between T line-based anteversion and native anteversion was 2.7° (5mm cut) and 3.5° (10mm cut).
• These differences were within acceptable ranges, indicating compatibility.
• The T line provides a reliable reference for stem anteversion in DDH.

Conclusions:

• T line-based femoral stem anteversion is a viable and compatible method in THA for DDH.
• This technique can help achieve appropriate femoral alignment in complex hip anatomy.
• Further research may explore clinical outcomes using this method.