Background:
A 43-year-old otherwise healthy man presented to the ED with ankle pain and swelling. Patient was playing basketball 5 days ago and twisted his left ankle. He initially presented to an outside hospital where he was told he had an “ankle” fracture and was splinted with a short leg posterior splint. He presented to our ED for worsening pain and swelling of his lower leg. On exam, the patient has ecchymosis and edema of the ankle extending proximally just inferior to the knee. There was pain with tibio-fibular compression and point tenderness was present over the medial malleolus and proximal fibula with overlying ecchymosis. The compartments were soft and the leg was neurovascularly intact. The patient was sent for radiographs.
Fig 1. Mildly displaced oblique fracture involving the proximal fibular metaphysis.
Fig 2. Asymmetric widening of the medial ankle mortise which measures approximately 5.5mm.
Why it matters:
The Maisonneuve fracture involves a deltoid ligament rupture (or medial malleolus fracture) and a spiral fracture of the proximal third of the fibula. This injury occurs with forceful external rotation of the ankle; causing a tear in the distal tibiofibular syndesmosis. Patients initially present with significant ankle pain and often very little pain over the fibular fracture; making it easy to ignore. This can be particularly problematic if the deltoid ligament rupture is not accompanied by a widened ankle mortise and the significant underlying injury goes unnoticed. To avoid missing this injury, the axiom exists that the knee (proximal fibula) should always be examined in patients presenting with ankle injury. When diagnosed, a long leg posterior splint is applied and the patient is given crutches. If not addressed appropriately, a Maisonneuve fracture creates an unstable ankle joint that can lead to long term ankle instability and early onset arthritis.
Proper definitive treatment includes reduction of the proximal fibula and medial malleolus to achieve stabilization. Additionally, repair of the deltoid ligament and distal tibiofibular syndesmosis aims to restore ankle mortise stability. Treatment can be achieved non-operatively if only the posterior ligaments of the tibiofibular syndesmosis are partially damaged. Otherwise, most cases require operative repair.
Created By:
Maria Gomez, M.D.
Emergency Medicine Resident | PGY2
Cook County Emergency Medicine
Reviewed By:
Scott Sherman, M.D.
Associate Program Director | Cook County Emergency Medicine
References:
Taweel NR, Raikin SM, Karanjia HN, Ahmad J. The proximal fibula should be examined in all patients with ankle injury: a case series of missed maisonneuve fractures. J Emerg Med. 2013 Feb;44(2):e251-5. doi: 10.1016/j.jemermed.2012.09.016. Epub 2012 Oct 15. PMID: 23079149.
He JQ, Ma XL, Xin JY, Cao HB, Li N, Sun ZH, Wang GX, Fu X, Zhao B, Hu FK. Pathoanatomy and Injury Mechanism of Typical Maisonneuve Fracture. Orthop Surg. 2020 Dec;12(6):1644-1651. doi: 10.1111/os.12733. Epub 2020 Sep 7. PMID: 32896104; PMCID: PMC7767678.