Reliability of Intraoperative 3D-Fluoroscopic Imaging in Assessing Acetabular Fracture Reduction

Area of Science:

• Orthopedic surgery
• Radiology
• Trauma care

Background:

• Acetabular fractures require precise reduction for optimal outcomes.
• Intraoperative imaging is crucial for guiding surgical decisions.
• The reliability of intraoperative 3D fluoroscopy for acetabular fracture assessment is not well-established.

Purpose of the Study:

• To evaluate the image quality and reliability of intraoperative 3D fluoroscopy.
• To compare intraoperative 3D fluoroscopy with postoperative CT for assessing acetabular reduction.
• To determine the accuracy of 3D fluoroscopy in measuring gap and step-off in acetabular fractures.

Main Methods:

• Retrospective chart review of adult patients with acetabular fractures (OTA/AO 62A, 62B, 62C).
• Comparison of measurements (gap, step-off) from intraoperative 3D fluoroscopy and postoperative CT.
• Image quality and inter/intra-observer reliability assessed using standardized scales and interclass correlation coefficients (ICC).

Main Results:

• Over 50% of 3D fluoroscopy scans were rated as poor quality (1/5 or 2/5), while all CT scans were rated 3/5 or higher.
• Surgeons reported high confidence in CT measurements (70%) versus 3D fluoroscopy (2.8%).
• Moderate agreement was found between 3D fluoroscopy and CT for gap and step-off, with CT demonstrating superior intra- and inter-observer reliability.

Conclusions:

• Intraoperative 3D fluoroscopy demonstrates significantly lower image quality and reliability than postoperative CT for acetabular fracture reduction assessment.
• 3D fluoroscopy exhibits poor interrater reliability, limiting its utility for final reduction evaluations.
• Postoperative CT is recommended for definitive assessment of acetabular fracture reduction, especially for weight-bearing dome and posterior wall fractures.