Is fixation of the medial malleolus necessary in unstable ankle fractures?

Introduction: It is unclear whether the medial malleolus in unstable bi- and tri- malleolar ankle fractures without medial talar displacement should be addressed surgically. This study reviews a fixation protocol for the medial malleolar component of unstable bi- or tri- malleolar ankle fractures.

Materials And Methods: Two hundred fifty-seven patients who sustained bi- (AO/OTA 44-B2) or tri- (AO/OTA 44-B3) malleolar ankle fractures between January 2005 and August 2019 at two Level 1 trauma centers were retrospectively identified. Medial malleolar fractures were defined as anterior, supra or intercollicular fractures based on the exit of the posterior fracture line. Fixation of the medial malleolar component was performed based on surgical algorithm. Only large or significantly displaced medial malleolar fractures were fixed if the soft tissues were amenable. Primary outcome measure was the presence of medial-sided ankle pain after operative or non-operative treatment of the medial malleolar fracture after a minimum follow up of 6 months. Presence of pain was defined by a pain score of 3 or higher on a 10-point VAS pain score at the site of the medial malleolar fracture.

Results: Significantly more patients in the supracollicular group reported the presence of pain when this type was not fixed versus fixed (28 vs 14%, p = 0.0094). Significantly more patients in the anterior collicular subgroup reported the presence of pain when this type was fixed versus not fixed (40 vs 10%, p = 0.0438). There was no difference in the number of patients reporting pain in the intercollicular group when comparing those who were fixed versus not fixed, (21 vs 22%, p = 1.000).

Conclusions: When examining post-operative pain, not all medial malleolar fractures require fixation when appropriately selected based on fracture pattern. Only 10% of patients with anterior collicular fractures reported pain after non operative management. Unsurprisingly, more patients in the supracollicular fractures reported pain without surgery compared to with surgery. Fracture pattern should be considered in the treatment algorithm for the medial malleolar component in bi- and tri- malleolar fractures.