The Accuracy of Acetabular Component Position Using a Novel Method to Determine Anteversion

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Comparing surgical approaches for total hip arthroplasty (THA) is crucial for optimizing patient outcomes.
• Acetabular component positioning directly impacts THA success and longevity.
• Understanding differences between anterior and posterior approaches is key for surgical technique refinement.

Purpose of the Study:

• To compare acetabular component positioning, leg length discrepancy, and hip offset between anterior and posterior approaches in THA.
• To evaluate a novel method for determining acetabular anteversion using C-arm tilt angle in the anterior approach.

Main Methods:

• A matched-cohort study of 100 anterior THA and 100 posterior THA patients.
• Postoperative radiographs were analyzed for cup inclination, cup anteversion, leg length discrepancy, and hip offset.
• A novel C-arm tilt angle technique was used to assess acetabular anteversion in the anterior approach group.

Main Results:

• The anterior approach achieved a higher percentage of acetabular cups within the safe zone (100% vs. 81%).
• Mean acetabular anteversion was 18.4° for the anterior approach and 23.6° for the posterior approach.
• No significant differences were observed in hip offset restoration or leg length discrepancy between the two approaches.

Conclusions:

• Intraoperative fluoroscopy-assisted direct anterior approach is associated with improved acetabular component positioning.
• The direct anterior approach did not show a benefit in restoring hip offset or leg length compared to the posterior approach.
• The novel C-arm tilt plane technique provides a reliable method for assessing acetabular anteversion in anterior THA.