The outcome of a single percutaneous cannulated screw fixation in posterior malleolus fracture accompanied by medial or lateral malleolus fracture

Abstract

Category: Trauma Introduction/Purpose: Posterior malleolus fractures occur most commonly in the setting of a rotational ankle fracture. In the treatment of posterior malleolus fractures, the indications for the surgical procedure are determined by the size of the fragment and the articular congruity of the tibiotalar joint. In general, the size of the bone fragment is known to be an indication of surgery if it involves more than 25% of the joint surface, and if it is less than that, anatomical reduction and fixation of only lateral or medial malleolus was suggested. We evaluate the clinical and radiological results of fixation and early range of motion exercise using a single cannulated screw when the fragment of the posterior malleolus fracture is less than 25%. Methods: Among 60 patients with SER stage 3 or 4 who had undergone surgery from March 2010 to March 2014, percutaneous cannulated screw fixation was performed for posterior malleolus in 30 cases (Group 1). In the other 30 cases (Group 2), we did not perform the fixation for posterior malleolus fracture and only cast immobilization was done after fixation for lateral or medial malleolus. Mean follow-up period was 14.8 weeks(12~18) for the Group 1, 12.9 weeks(12~18) for Group 2. Mean age of patients was 46.6(19~78) for Group 1, 50.2(19~74) for Group 2. The range of motion was checked at week 2, 4, 12, and at last follow-up. Results: There was no significant difference of time to union and union rate between two groups, and AOFAS score between two groups also showed no significant difference(91.94(83~100) vs 90.8(85~100), p = 0.45). The range of motion of ankle joint at the final follow-up showed significant difference (Ankle ROM 52.7’ (45’~65’) vs 45.3’(35’~65’), (p<0.01) and complications between two groups also showed no significant difference. Conclusion: A single percutaneous cannulated screw fixation in posterior malleolus fracture accompanied by medial or lateral malleolus fracture can be performed in fractures with small fragment size and minimal displacement. We found that it can be a effective method to achieve early and wide range of motion of ankle joint after posterior mallolus fracture.