AANA Lab Course 908-Foot and Ankle Arthroscopy (APEx)-Syndesmosis Injury_ How I Diagnose and Treat-Phinit Phisitkul, M.D.

Syndesmosis Injury_ How I Diagnose and Treat-Phinit Phisitkul, M.D.

Pdf Summary

This article by Dr. Phinit Phisitkul discusses the diagnosis and treatment of syndesmosis injuries, a type of high ankle sprain involving the ligaments connecting the tibia and fibula. Diagnosis relies on a combination of clinical suspicion and imaging studies, including radiographs and MRI. MRI shows the highest sensitivity (near 100%) for identifying syndesmotic disruptions compared to standard AP and mortise X-rays, which have lower sensitivity.<br /><br />Radiographic criteria, such as a 2mm widening between tibia and fibula, are used, but studies show limitations in detecting ligament injury and reduction adequacy. Arthroscopy and intraoperative stress X-rays improve diagnostic accuracy. Direct visualization during surgery reduces malreduction rates compared to fluoroscopy alone.<br /><br />Malreduction is common with traditional screw fixation, often due to improper clamp placement and fibular shortening or malrotation. The B-2 clamping technique—placing the medial clamp tine on the anterior third of the tibia and on the fibular ridge—helps achieve better anatomic reduction aligned with the tibial plafond surface. Flexible fixation using suture-button devices is increasingly favored for certain injury types, allowing early motion and weightbearing, although screws remain necessary in cases like Maisonneuve fractures or extensive bony injuries.<br /><br />Additional treatments include anatomic fixation of the fibula and posterior malleolus, as well as deltoid ligament repair when deep deltoid disruption is present. Intraoperative CT imaging has proven valuable in detecting malreductions, prompting treatment alterations in about one-third of cases studied.<br /><br />Dr. Phisitkul's preferred approach integrates preoperative MRI, targeted arthroscopy if needed, direct visualization of the syndesmosis during surgery, B-2 clamping technique for reduction, and a flexible fixation strategy tailored to injury pattern. Future directions include refinement of fixation methods and individualized treatment strategies to optimize outcomes.

Keywords

syndesmosis injuries

high ankle sprain

tibia fibula ligaments

MRI diagnosis

radiographic criteria

arthroscopy

B-2 clamping technique

suture-button fixation

malreduction

intraoperative CT imaging