Radiological assessment of ankle syndesmotic reduction

Area of Science:

• Orthopedic surgery
• Radiology
• Biomechanics

Background:

• Intraoperative assessment of syndesmotic reduction adequacy is clinically challenging.
• Accurate reduction is crucial for ankle stability and function.
• Existing methods may lack precision in evaluating syndesmotic alignment.

Purpose of the Study:

• To develop and validate novel radiographic measures on the lateral ankle view.
• To assess the relationship between the tibia and fibula after simulated syndesmotic malreduction.
• To evaluate the impact of malreduction on standard mortise measurements.

Main Methods:

• Lateral ankle radiographs were obtained from cadaveric specimens.
• Syndesmosis was divided and fibular displacement simulated in 2mm increments.
• Anterior fibular line ratio (AFL ratio) and posterior fibular line distance (PFL distance) were measured.
• Inter- and intraobserver reliability was assessed.

Main Results:

• The AFL ratio and PFL distance demonstrated near-perfect inter- and intraobserver reliability.
• In uninjured specimens, specific AFL and PFL measurements were established as normal.
• Significant differences in AFL ratio and PFL distance were observed with 2mm, 4mm, and 6mm of posterior fibular displacement.

Conclusions:

• The developed AFL ratio and PFL distance are reproducible radiographic measures.
• These measures can reliably detect as little as 2mm of sagittal fibular displacement.
• The AFL ratio and PFL distance serve as valuable adjuncts for assessing syndesmotic reduction accuracy.