Ultrasound-based computer navigation of the acetabular component: a feasibility study

Area of Science:

• Orthopedic Surgery
• Medical Imaging Technology
• Surgical Navigation

Background:

• Assessing the accuracy of anterior pelvic reference plane (APP) registration and acetabular cup orientation is crucial for hip replacement surgery.
• Investigating the feasibility of ultrasound-based navigation in cadavers with varying body mass index (BMI) is essential for clinical application.

Purpose of the Study:

• To evaluate the accuracy and reproducibility of ultrasound-based navigation for APP registration.
• To determine the precision of acetabular cup orientation using this navigation system in cadavers with different BMIs.

Main Methods:

• Five observers registered the APP five times in two cadavers (BMIs: 32 kg/m² and 25 kg/m²) using an ultrasound navigation system.
• Errors in landmark determination, APP orientation, and acetabular cup orientation were calculated by comparing with CT-derived reference landmarks.
• Reproducibility of cup adduction and anteversion angles was assessed.

Main Results:

• Mean errors for APP rotation and version were 0.5° ± 1.0° and -0.4° ± 2.0°, respectively.
• Mean errors for cup abduction and anteversion were -0.1° ± 1.0° and -0.4° ± 2.7°, respectively.
• High reproducibility was observed for the resulting cup adduction and anteversion angles.

Conclusions:

• Ultrasound navigation is a highly accurate tool for reproducible APP registration.
• This technology enables accurate and precise intraoperative determination of acetabular cup orientation.
• The findings suggest efficacy even in patients with increased BMI.