A quantitative method to assess focal acetabular overcoverage resulting from pincer deformity using CT data.

Area of Science:

• Orthopedic surgery
• Radiology
• Medical imaging analysis

Background:

• Current methods for assessing focal acetabular overcoverage lack consistency and quantitative accuracy.
• Pincer deformity, characterized by acetabular overcoverage, requires precise measurement for effective treatment.

Purpose of the Study:

• To develop and validate a CT-based method for precise quantification of focal acetabular overcoverage.
• To evaluate the consistency of the proposed measurement technique.
• To compare CT-based measurements with conventional radiographic assessments.

Main Methods:

• A novel algorithm was developed to measure focal acetabular overcoverage using CT scans, with pelvic alignment correction.
• The method's consistency was assessed by two independent observers using cadaveric pelvic CT scans.
• Measurements from 3D CT data were compared with those from reconstructed radiographs.

Main Results:

• The developed software demonstrated feasibility in producing consistent and quantitative measurements of acetabular overcoverage.
• Observer agreement in pelvic alignment was high, with an average difference of 0.42°, indicating method consistency.
• Significant differences were observed between 3D CT measurements and simulated radiograph assessments.

Conclusions:

• The proposed CT-based method provides a consistent and quantitative approach to measuring focal acetabular overcoverage, accounting for pelvic tilt and rotation.
• Simulated AP hip radiographs tend to overestimate acetabular rim overcoverage in pincer deformities.
• This technique holds potential for improving preoperative diagnosis and surgical planning for pincer deformities.