Skip to Main Content

Given the mobility of the ankle joint and our bipedal existence, ankle injuries are a common complaint to the ED. These injuries have typically been seen in patients <40 years of age with an equal male and female distribution. Fractures of the lateral malleolus have been seen in 15% of all ankle injuries, but are more prevalent in men <50 years="" old="" and="" in="" women="">50 years old.1,2 In the elderly population, a review of Medicare claims from 1998 to 2000 found white women to have the highest prevalence of ankle fractures (5.8 per 1000) compared with the lowest in nonwhite men (1.5 per 1000). There has also been noted to be geographic variability, with certain regions having a higher prevalence of fractures with variation in those that underwent operative fixation.3 In terms of ankle sprains, previous ankle sprain has been cited as a risk factor.4 Sports like soccer, basketball, rugby, and football have been found to be activities with higher incidences of ankle injuries.4,5 In sports-related injuries, ankle sprains have been seen with an incidence anywhere from 0.68 to 3.85 sprains per 100 person-days of exposure.6

The proximal part of the ankle mortise is comprised of the distal fibula and tibia that fits on top of the talus. These bones are wider anteriorly than posteriorly. Joint stability is provided by medial and lateral malleoli extending on either side of the talus. The medial deltoid ligament, lateral ligament complex, and syndesmosis are the three distinct groups of ligaments that stabilize the ankle.7 The medial collateral (or deltoid ligament) is the strongest of these ligaments and is a thick, triangular band of tissue originating from the medial malleolus. The lateral ligament complex consists of the lateral malleolus that attaches to the anterior and posterior aspects of the talus and calcaneus by the anterior talofibular, posterior talofibular, and calcaneofibular ligaments, respectively. This group, the anterior ligament in particular, is the weakest and most commonly injured in lateral sprains. The syndesmosis is a group of four distinct ligaments attaching the distal tibia to the fibula just above the talus (Figure 273-1). Due to these ligaments, the fibula is allowed to rotate and carries approximately 16% of the axial load.7

The ankle is considered a hinged joint, but ligamentous attachments allow for some rotation and translation within the mortise of the talar dome.7 Branches of the sciatic nerve, the superficial peroneal, deep peroneal, peroneal, and tibial, innervate the four muscle groups of the ankle joint with branches of the popliteal artery serving as the blood supply. The tibialis anterior, extensor digitorum longus, and extensor hallucis longus muscles run over the anterior aspect of the joint and are responsible for dorsiflexion. Inversion is accomplished by the tibialis posterior, flexor digitorum longus, and flexor hallucis longus. The peroneus longus and brevis muscles, sharing a common synovial ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.