Nonoperative Treatment of the Medial Malleolus in Bimalleolar and Trimalleolar Ankle Fractures: A Randomized Controlled Trial    

SLR - April 2015 - Joshua P. Edlinger

Reference: Hoelsbrekken SE, Kaul-Jensen K, Mørch T, Vika H, Clementsen T, Paulsrud Ø, Petursson G, Stiris M, Strømsøe K. Nonoperative Treatment of the Medial Malleolus in Bimalleolar and Trimalleolar Ankle Fractures: A Randomized Controlled Trial.  J Orthop Trauma. 2013 Nov; 27(11): 633-7.

Scientific Literature Review
 
Reviewed By: Joshua P. Edlinger, DPM
Residency Program: Kaiser SF Bay Area Foot and Ankle Residency Program

Podiatric Relevance: When faced with various fracture patterns associated with ankle trauma, it is of interest to the foot and ankle surgeon to be aware of recent literature refuting the need for implementation of internal fixation in non-displaced isolated fractures of the medial malleolus. While there have been recent studies conducted to this effect, there has been no research delineating whether fixation of the non-displaced medial malleolar component in bimalleolar and trimalleolar ankle fractures would definitively affect functional outcomes. The aim of this study was to compare internal fixation with no fixation of the medial malleolus in bimalleolar and trimalleolar fractures after ORIF of the lateral component (including the syndesmosis and/or posterior malleolus if indicated).

The authors of this study hypothesize whether it is truly necessary to treat a non-displaced (less than 2-mm on radiographic AP view) medial malleolar fracture with internal fixation after adequate ORIF of the lateral component.

Methods:  One hundred patients ages 18-65 with bimalleolar or trimalleolar Orthopaedic Trauma Association (OTA/AO) type 44 ankle fractures (B2, B3, C2 and C3) with displacement of the medial malleolus less than 2 mm after ORIF of the lateral component, were randomized into two groups. One group was treated with internal fixation of the medial malleolus, while the second group was not.  American Orthopaedic Foot and Ankle Society ankle hind foot score (AOFAS), The Olerud Molander Ankle (OMA) score, and visual analogue pain scale (VAS) scores were used for functional comparison of outcomes between groups.  

Results:  There were no significant differences between the 2 groups with respect to OMA (P = 0.91), AOFAS (P = 0.85), VAS (P = 0.85), or the development of osteoarthritis (P = 0.22). None of the patients in the internal fixation group developed a nonunion of the medial malleolus, while 4 patients treated with no fixation developed non-unions.  However, these patients reported no functional disabilities and reported OMA, AOFAS, and VAS scores better than average. Eighteen patients were lost to follow up. Reoperation and complication rates were comparable between both operative and non-operative groups. The median follow-up time for the study was 39 months (range: 24–72).

Conclusions:  The authors conclude that sole fixation of the lateral malleolus or lateral component is a possible treatment option, but given the uncertainty related to progression of post-traumatic arthritis, non-operative treatment of the medial malleolus should be restricted to situations where medial soft tissue injuries do not permit surgery.

Given the small sample size, lack of standardized endpoints, and short follow up time, there is doubt as to the effects of untreated medial malleolar fractures on the development of post-traumatic ankle arthritis.  If further randomized controlled trials with larger sample size and long-term follow up supported the findings from this study, it would likely cause me to further consider which non-displaced medial ankle fractures would require fixation once the lateral component is stabilized.