Ankle Dislocation Management in the ED Clinical Presentation

Updated: Jan 26, 2022
  • Author: James E Keany, MD, FACEP; Chief Editor: Trevor John Mills, MD, MPH  more...
  • Print
Presentation

History

When a patient presents with ankle injury, a detailed history regarding the mechanism of injury often helps predict the types of injuries to be expected. Furthermore, an understanding of the injury mechanism aids treatment. Because of the inherent stability of the ankle joint mortise and surrounding tendons and ligaments, dislocation is usually caused by high-energy trauma that causes plantar flexion of the ankle combined with either inversion or eversion stress upon the foot. [2] Four types of dislocations are seen around the ankle joint: posterior, anterior, lateral, and superior.

Posterior

A posterior dislocation is the most common type of ankle dislocation. [14] The talus moves in a posterior direction in relation to the distal tibia as force drives the foot backward. [15] The wider anterior talus wedges back, resulting in forced widening of the joint. This must be accompanied by disruption if the tibiofibular syndesmosis is involved, or fracture if the lateral malleolus is affected, which occurs most commonly when the ankle is plantar flexed.

Anterior

Anterior dislocations result from the foot being forced anteriorly at the ankle joint.

Typically, anterior dislocation occurs when the foot is fixed and a posterior force is applied to the tibia, or it can occur with forced dorsiflexion.

Lateral

Lateral dislocations result from forced inversion, eversion, or external or internal rotation of the ankle. They are associated uniformly with fractures of the malleoli or the distal fibula or both.

Superior

Diastasis occurs when a force drives the talus upward into the mortise. These dislocations usually are the result of a fall from a height. In such cases, the patient should be evaluated carefully for concomitant spine injury and fracture of the calcaneus.

Next:

Complications

The amount of force and the level of capsular disruption required to dislocate the inherently stable joint can lead to significant injury with lasting effects. To a limited extent, prompt intervention can reduce the risk of complications.

Complications of ankle dislocation may include the following:

  • Nonunion or malunion

  • Synostosis

  • Entrapment of the tibialis posterior tendon or of a fracture fragment

  • Cartilaginous injury

  • Osteochondral fractures of the talar dome

  • Joint stiffness and decreased range of motion (eg, osteoarthritis [16] )

  • Arterial injury (anterior and posterior tibial, peroneal)

  • Compartment syndrome (rare)

With open reduction internal fixation (ORIF), hardware is generally routinely removed after 4 months to allow restoration of joint motion and to avoid complications of hardware failure. Little consensus has been reached regarding the optimal time for hardware removal, or whether hardware retention leads to adverse outcomes. [9]

Previous