Anterior anchor placement in deltoid ligament augmentation for the treatment of ankle fracture with both syndesmosis and deltoid ligament injury: A biomechanical study

Abstract

Background: In deltoid ligament (DL) augmentation for the treatment of ankle fracture with both syndesmosis and DL injuries, the exact suture anchor insertion point of the ligament on the talus is likely to influence the repair strength. However, the ideal anchor position remains unclear. This biomechanical study aimed to compare the external rotation stability between cadaveric ankle fracture models with different insertion sites of the suture anchor. Methods: This biomechanical study evaluated seven formalin-fixed cadaveric ankle specimens. An ankle injury model with both syndesmotic disruption and DL injury was created and two suture anchor placements were tested: anterior and central placement on the talus side of the DL insertion footprint. External rotation stability was assessed by measuring the medial clear space and tibiofibular clear space. Results: There was no significant difference between the two groups in the tibiofibular clear space widening (p > .05). However, the anterior placement of the suture anchor significantly reduced the medial clear space widening compared with central placement (p < .05), suggesting better resistance to external rotation and talar anterior dislocation. Conclusions: Anterior placement of the suture anchor in DL augmentation may offer improved stability against external rotation forces in ankle fractures with syndesmotic and DL injuries. This study provides biomechanical evidence supporting the potential advantages of this technique.

Keywords: biomechanics; deltoid ligament; syndesmosis; trauma.