Ankle
fracture Maisonneuve Fracture – Everything You Need to Know
Maisonneuve fracture involves fracture of the proximal
fibula associated with an occult and unstable injury of the ankle. The problem
in these patients occur when the ankle injury is presented without a fracture
of the lateral malleolus, or the medial malleolus and the injury is mistakenly
diagnosed as an ankle sprain and the proximal fibular fracture is missed. Examine
the leg for tenderness in the proximal fibula to diagnose a proximal fibula
fracture. The patient could be mistakenly treated for having an isolated
proximal fibular fracture alone and the ankle injury is missed.
High index of
suspicion is necessary to diagnose and treat this injury. Maisonneuve fracture
equals syndesmotic injury. Syndesmotic Injury equals Syndesmotic Reduction and
Fixation. If ankle x-rays show medial or posterior malleolus fracture, or a
medial clear space widening with no fracture of the lateral malleolus, then you
must obtain a long-leg films to assess possible proximal fibular fracture. Clinical
examination of their entire leg for pain and tenderness in addition to long leg
films of the entire leg that includes the ankle, and the knee is mandatory in
case of the patient with approximate fibular fracture to exclude the presence of
an additional ankle injury, or if the patient has an unexplained increase in the
medial clear space of the ankle joint. You should be searching for the presence
of a high fibular fracture. Look for signs of syndesmotic injury such as an
unexplained increase in medial clear space or tibiofibular clear space is
widened and it should be less than 5 millimeters.
So how do you explain this injury? It is explained by the
presence of rotation force to the ankle with transmission of the force through
the interosseous membrane, which exits through a proximal fibular fracture. Maisonneuve
fracture occurs from external rotation of the foot, most often with pronation
mechanism. This force has to go somewhere! If you don't see a fracture of the
fibula then do the squeeze test or the external rotation stress test (both will
show syndesmotic). The injury can involve the deltoid ligament injury or medial
malleolar fracture medially and a fibular fracture proximally. Additionally, the
tibiofibular ligaments are also involved, which can be the anterior
tibiofibular ligament, interosseous ligament, the posterior tibiofibular ligament
or posterior malleolar fracture. This looks like a very unstable ankle injury
that may not be very obvious at presentation and you have to look out for it.
So how do you treat an Maisonneuve Fracture? This treated by
fixation of the tibiofibular syndesmotic injury (key of treatment) or
syndesmotic screws. if you have a medial site injury and there is a tear of the
deltoid ligament, leave it alone. if there's a medial malleolus fracture you
should fix that of the lateral side if there's approximate fibular fracture
leave it alone. If there is a medial malleolar fracture, it should be fixed. If
there is a proximal fibular fracture on the lateral side, leave it alone. As
for the Syndesmotic Injury, the fixation has to be stable and adequate. Because
of the magnitude of the injury, the Maisonneuve fracture may require more
syndesmotic screws than with a routine ankle fracture with syndesmotic injury. After
the fixation you will give a short leg non-weight bearing splint for six to
eight weeks. Here is a patient taste example: the proximal fibular fracture and
you can see increase in the medial clear space and you can see that the
syndesmosis is widened. You can see that in the posterior malleolar fracture
the patient is fixed with syndesmotic screws.
