SLR - September 2019 - Amanda G. Borrelli
Reference: Mason LW, Kaye A, Widnall J, Redfern J, Molloy A. Posterior Malleolar Ankle Fracture an Effort at Improving Outcomes. Journal of Bone and Joint Surgery Open Access. 4(2):e0039, April-June 2019Scientific Literature Review
Reviewed By: Amanda G. Borrelli, DPM
Residency Program: Hoboken University Medical Center – Hoboken, NJ
Podiatric Relevance: A common discussion when treating trimalleolar ankle fractures is whether or not the surgically fixate the posterior malleolar fragment. Traditionally, a posterior malleolar fracture fragment involving approximately 25 percent of the articular surface of the distal tibia require open reduction internal fixation. Recent literature has illustrated that posterior malleolar fracture outcomes have been poor regardless of posterior malleolar fracture size. Mason et al. created a classification system to describe posterior malleolar fracture fragments, in regards to the mechanism of injury, with a suggested treatment and surgical approach to the posterior malleolus. This study reviewed treatments of posterior malleolar fractures, utilizing the treatment algorithm as dictated by the Mason and Molloy classification, and assessed their functional outcomes.
Methods: This study is a level IV retrospective study, which reviewed 50 patients with posterior malleolar fractures, treated by two authors, at a level-I trauma center between May 2015 and August 2016. A CT scan was performed on all patients which was then used to classify the injury based on the Mason and Malloy classification system. The classification then dictated the type of treatment based on the fracture pattern. Type-1 fractures were treated with syndesmotic fixation, Type-2A were treated with open reduction internal fixation with a posterolateral incision, Type 2-B were treated with open reduction internal fixation through a posteromedial incision or a posterolateral incision combined with a medial posteromedial incision. Prospective outcomes were then evaluated by using the Olerud-Molander Ankle Score and the EuroQol-5 Dimensions (EQ-D5) for patient symptoms and health-related quality of life.
Results: Of the 50 patients recorded, the overall Olerud-Molander Ankle Score was 74.1 out of 100. There were 17 Type-1 fractures, with a score of 75.9; 12 Type-2A fractures, with a score of 75.0; 10 Type-2B fractures, with a score of 74.0; and 11 Type-3 fractures with a score of 70.5. The functional results of this study (74.1 out of 100) were greater when compared to a previous multicenter trial (54.3 out of 100), which used the traditional principle of fixating the posterior malleolar fragment if >25 percent of articular surface was involved.
Conclusions: The authors concluded that there was an increase in the Olerud-Molander Ankle Score, for all types of posterior malleolar fractures, when treated utilizing the Mason and Molloy classification’s suggested surgical approach. There were several limitations in this study, including potential selection bias being that it was a retrospective study, short duration of follow up assessment given that outcomes may improve with time, and the fact that the surgeries were performed by two different surgeons. When considering surgical intervention for posterior malleolar fractures, this study has shown that utilizing the Mason and Malloy classification and treatment algorithm, can lead to potential increases in functional outcomes.