SLR - January 2021 - Steven L. Stuto

Does Repair of Deltoid Ligament Contribute to Restoring a Mortise in SER Type IV Ankle Fracture with Syndesmotic Diastasis?

Reference: Choi, Seongju, et al. “Does Repair of Deltoid Ligament Contribute to Restoring a Mortise in SER Type IV Ankle Fracture with Syndesmotic Diastasis?” Archives of Orthopaedic and Trauma Surgery, 2020, doi:10.1007/s00402-020-03645-7. 

Level of Evidence: Level III

Scientific Literature Review

Reviewed By: Steven L. Stuto, DPM
Residency Program: University Hospital – Newark, NJ

Podiatric Relevance: Do all ankle fractures need to have a deltoid ligament (DL) repair? There remains a debate if the DL needs to be repaired after anatomical reduction and rigid internal fixation is performed to the lateral malleolus. Ankle fractures were found in previous studies to have a DL injury in 39.6 percent of patients. In a subsequent study, 58.3 percent of patients with ankle fractures were also found to have a DL injury with MRI evaluation. 

Methods: This article is a retrospective study performed between April 2011 and August 2017 to evaluate the clinical and radiographic outcomes of repaired ankle fractures. Inclusion criteria per the article was acute SER IV closed ankle fractures according to Lauge-Hansen Classification without medial malleolus fractures, adult older than 18, preoperative medial clear space (MCS) >6 millimeters in ankle mortise x-rays, widening of the syndesmosis on preoperative CT and at least one year of follow up. There was a total of 34 patients (19 patients with DL repair and 15 patients with no DL repair). DL repair differed depending on the rupture. A suture Anchor was used if there was an avulsion of the DL from its insertion on the medial malleolus otherwise DL was repaired with absorbable polydioxanone (PDS) in an interrupted suture technique fashion. 

Results: In the 15 patients with no repair to the DL, the mean preoperative MCS was 7.1 ± 1.9 millimeters, the mean immediate postoperative MCS was 3.3 ± 0.6 millimeters and the final follow-up MCS was 3.6 ± 0.7 millimeters. For the 19 patients with a DL repair, the mortise X-rays showed the mean preoperative MCS was 8.3 ± 1.8 millimeters and the mean immediate postoperative MCS was 3.2 ± 0.6 millimeters. Between the two groups, there was no significant difference in the radiographic outcomes, however, in four out of the 19 patients with the DL repaired, there was osteochondral injuries found to the talus. There was no statistical difference in the clinical outcomes between the two groups on the Foot Function Index.

Conclusions: The study concluded that the postoperative radiographs of SER type four ankle fracture had reduced MCSs, reduced clear space (CS), and increased overlap space (OS), which confirmed mortise restoration in both groups. The comparable results between the DL repair group and the DL group with no repair suggests that syndesmotic reduction could be much more important than DL repair with regard to restoring the mortise and maintaining ankle stability in ankle fractures. The sample size was small and larger studies with longer follow up would be helpful in determining if the presence of the osteochondal lesions in the DL group is clinically relevant.

Educational Opportunities