Ankle Injury: Can You Find the Twist?
Ankle injuries are extremely common but aren't always straightforward. Look at this patient's history and x-rays. What do you see?
A 40-year-old man injures his ankle when it twists badly after he catches it on some tree roots while walking on a slope. He states that he basically lost his balance, caught his toes on the root, and then fell.  He denies any other injuries, but is unable to bear weight. He has no significant past medical history and takes no medications.
On examination, he has a good pulse, the skin is intact without ecchymosis, and the compartments are soft.  His right ankle is tender both medially and laterally with mild swelling, but the foot is not tender. Pulses are symmetric. The rest of his exam is normal. X-rays of the ankle are ordered and are shown on the next slide.
Note the widened medial mortise on the ankle film. The mortise is the space between the talus and the adjacent bones and normally is equal throughout. In this case it is wider than normal at the inner aspect of the medial malleolus.
There is also a fracture associated with this injury but it is not visible on the initial films of the ankle. It can be easily seen, however, when additional imaging is done.
The fracture is toward the top of the fibula near the knee. These findings are consistent with a sever injury involving not only the two findings on imaging but also disruption of the syndesmosis that connects the tibia and fibula between the knee and ankle.
A Maisonneuve injury is more serious than initial imaging often suggests and can easily be missed if you do not know what to look for. Treatment is usually surgical so splinting, non-weight-bearing (NWB) status and early referral to an orthopedist are important parts of early treatment. Complications include peroneal nerve injury and joint instability.For a quick review of other ankle injuries please, see the table below.
Half of all ankle sprains occur during sports activity but debilitating ankle injuries can be sustained by stepping off a curb or crossing an uneven driveway. The patient in the case study above got tangled up in tree roots on the day he hurt his ankle, along with 24,999 others in the United States.Can you tell from the x-ray image what kind of injury he has? What treatment would you recommend? When you're finished with the case, use the table below to brush up on your ankle injuries. ANKLE INJURIES from Quick Essentials Emergency Medicine 1-minute Consult pocketbook Ankle Fx:Stable: nondisplaced fibula. Treatment: cam walker or short leg cast Unstable: 2 bones or ligaments. Treatment: long leg cast, may need surgeryMisses:Talus, Maisonnueve (see below), calcaneus, effusion may mean an occult fractureAnkle sprain:Inversion most common mechanism.Exam:Check knee & foot, anterior drawer, squeeze test & external rotation for syndesmosis.Ottawa tool:No X-ray needed if malleoli, 5th metatarsal & navicular all non-tender and can walk 4 steps.Grades:1: pain w/o laxity.                 Rx: air splint, early range of motion2: laxity w/ good endpoint,limping.                                 Rx: air splint, early range of motion3: laxity w/o endpoint,can’t walk, ecchymosis.          Rx: NWB, posterior splint, cast                                                     (surgery)Surgery:Indications: deltoid torn and intrarticular w/ wide mortise, syndesmosis tear w/ wide mortise.Maisonneuve:Medial ankle injury with proximal fibula fracture. Ankle film may show only wide mortise.Injury:External rotation mechanism; syndesmosis torn, peroneal nerve injury.Treatment:ORIF (open reduction with internal fixation)[[{"type":"media","view_mode":"media_crop","fid":"39667","attributes":{"alt":"","class":"media-image","id":"media_crop_250863670543","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"3989","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"width: 139px; height: 158px;","title":" ","typeof":"foaf:Image"}}]]Click image for details.
