Mortise-view x-ray of a 16-year-old girl’s right ankle after a soccer injury.
Lateral x-ray of the girl’s ankle.
Lateral x-ray of the affected leg.
Anteroposterior x-ray of the affected leg.
A 16-year-old female presents with pain that developed in the right ankle following a soccer injury. The injury occurred 2 days earlier when the patient turned her ankle awkwardly, having stepped on an opponent’s cleat. She has been unable to walk on the ankle since the injury. On examination, swelling and ecchymosis are noted over the lateral and medial ankle. There is tenderness to palpation over the proximal fibula, laterally over the anterior talofibular ligament and medially over the deltoid ligament. X-rays of the proximal tibia and ankle are taken.
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The patient presents with a spiral fracture of the proximal fibula, with a suspected syndesmotic injury on examination. These findings are consistent with a Maisonneuve fracture.
A Maisonneuve fracture results from an external-rotation force in the ankle that causes either a medial malleolus avulsion fracture or disruption of the medial deltoid ligaments. The energy of the injury travels up the interosseous membrane proximally and exits out of the proximal fibula as a spiral fracture.
Obtaining stress views is necessary to determine the degree of syndesmotic injury, as static x-rays may be normal. Widening of the medial clear space during stress views confirms the diagnosis of an unstable syndesmotic injury. Unstable injuries require syndesmotic fixation, typically with 1 or 2 syndesmotic screws. The patient is kept non-weight-bearing in a cast or boot postoperatively for 12 weeks. The screw is then removed at 3 months to prevent screw breakage when weight bearing is initiated.1
If no widening of the medial clear space is observed on stress views, then syndesmotic stability is assumed. Because proximal fibula spiral fractures do not all result in complete syndesmotic disruption, syndesmotic stress views are crucial when determining treatment. If stable, patients can be treated with cast immobilization and non-weight-bearing. Serial radiographs should be obtained over the first 4 weeks following the injury to ensure that syndesmosis remains stable.2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor-in-chief of the Journal of Orthopedics for Physician Assistants (JOPA).
- Zalavras C, Thordarson D. Ankle syndesmotic injury. Am Acad Orthop Surg. 2007;15(6):330-339.
- Maisonneuve fracture. Wheeless’ Textbook on Orthopedics website. Available at http://www.wheelessonline.com/ortho/maisonneuve_fracture. Updated May 22, 2012. Accessed March 28, 2016.