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Clinical Procedures > Musculoskeletal Procedures
Joint Reduction, Ankle Dislocation
Article Last Updated: Apr 8, 2008
AUTHOR AND EDITOR INFORMATION
Section 1 of 12  
Author: James Emanuel Rodriguez, MD, Staff Physician, Department of Emergency Medicine, New York University/Bellevue Hospital
James Emanuel Rodriguez is a member of the following medical societies: American College of Emergency Physicians, American College of Sports Medicine, and Emergency Medicine Residents Association
Coauthor(s):
Moira Davenport, MD, Attending Physician, Departments of Emergency Medicine and Orthopedic Surgery, Allegheny General Hospital
Editors: Erik D Schraga, MD, Consulting Staff, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates; Consulting Staff, Permanente Medical Group, Kaiser Permanente, Santa Clara Medical Center; Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine.com, Inc; Luis M Lovato, MD, Assistant Clinical Professor, David Geffen School of Medicine at UCLA; Director of Critical Care, Department of Emergency Medicine, Olive View/UCLA Medical Center; Gil Z Shlamovitz, MD, Assistant Professor of Emergency Medicine, University of Connecticut School of Medicine; Attending Physician, Emergency Department, Windham Memorial Community Hospital, Willimantic, CT; Attending Physician, Emergency Department, Hartford Hospital, Hartford, CT; Rick Kulkarni, MD, Medical Director, Assistant Professor of Surgery, Section of Emergency Medicine, Yale-New Haven Hospital
Author and Editor Disclosure
Synonyms and related keywords:
ankle fracture, ankle dislocation, ankle reduction, joint reduction, neurovascular examination, ankle splint, open injury, closed injury, ankle injury, sprained ankle, broken ankle, subtalar, subtalar joint, malleoli fracture, tibial fracture, talus dislocation, Ehlers-Danlos syndrome, plantar flexion, capsular ligaments, ankle inversion, ankle eversion, neurovascular compromise, posterior talus dislocation, anterior talus dislocation, posterior talus, anterior talus, lateral talus, lateral talus dislocation, medial talus, medial talus dislocation, long leg posterior splint, ankle splint, tibiotalar, tibiotalar dislocation, malleoli tent, talar head tent, open fracture, malleolus hypoplasia
The ankle is a unique modified saddle joint that, together with the subtalar joint, provides range of motion in several physical planes while maintaining stability. The ankle's complex function as a pivoting structure positioned to bear almost the entire weight of the body leaves it vulnerable to tremendous forces of injury; pure dislocation without associated fracture is rare.1 Dislocation of the ankle usually occurs with fractures of the malleoli or of the posterior aspect of the tibia because the ankle’s ligamentous structures are, in most cases, stronger than the osseous architecture. In addition to a strong association with fractures, ankle dislocations are often open because of the thin layer of tissue that lies over the malleoli. Posterior dislocation of the talus is the most common form of ankle dislocation, although medial, anterior, lateral, and superior dislocations have been well described. Individuals at increased risk for ankle dislocation injuries include those with a history of prior ankle fractures, ankle sprains, weakness of the peroneal muscles, malleolar hypoplasia, or ligamentous laxity such as may occur with Ehlers-Danlos syndrome and other connective tissue disorders. For more information on joint disorders, visit Medscape’s Joint Disorders Resource Center. An ankle dislocation represents a high force traumatic injury that often occurs in vehicular collisions or sports that involve jumping. The physician must, therefore, maintain a high index of suspicion for additional occult injuries. The energy of the traumatic insult usually either forces the ankle into a position of plantar flexion or strikes the ankle while it is already in a resting position of plantar flexion. Once in plantar flexion, all capsular ligaments of the ankle (with the exception of the posterior talofibular ligament) are stretched and, therefore, more susceptible to structural failure. In addition, plantar flexion brings the smaller surface area of the posterior edge of the talus into the mortise of the ankle, which makes translational forces on the talus more likely to dislodge it from the joint. Injuries that cause subsequent inversion of the ankle lead to posteromedial displacement and tears in the anterior talofibular and calcaneofibular ligaments. Eversion injuries are more likely to produce lateral dislocations and rupture of the talotibial ligament and medial joint capsule. Inversion injuries are more common as a result of axial loads from falls from significant height. The rupture of the ankle’s capsular structures is often severe, and the risk of infection secondary to open injury is often significant; however, prompt reduction and, when warranted, operative debridement and repair usually lead to excellent functional recovery and long-term prognosis. Immediate recognition and early reduction of the dislocated ankle are essential, as delayed reduction may lead to subsequent loss of range of motion and increased morbidity.
Evaluation of the ankle injury must sufficiently demonstrate that the dislocation is of the ankle joint, since subtalar dislocations may have presentations similar to those of dislocated ankles but are reduced with a different method.2 Applying the ankle reduction technique to a subtalar dislocation may lead to further injury and morbidity, and the 2 injuries may be clearly differentiated from each other radiographically. In addition to aiding in initial diagnosis, radiography helps to identify the anatomy of the fractures associated with ankle dislocations and should be attained both before and after reduction. Further means of identifying subtalar dislocations on the physical examination are described in the Pearls section.
- A traumatic ankle dislocation without associated neurovascular compromise and that has been elucidated by radiographic views of the ankle
- Such dislocations may or may not have an associated fracture and may or may not be open injuries.
- A traumatic ankle dislocation with associated neurovascular compromise
- These injuries may be evident by an open or closed ankle deformity with obvious malpositioning of the distal foot.
- In the context of neurovascular compromise, radiographic studies may be delayed until after the reduction. In such cases, the clinical presentation must assure the physician that this is an ankle, rather then subtalar, dislocation (see Pearls).
- Radiographic evidence of a subtalar, rather than ankle, dislocation2
- Clinical evidence of a subtalar, rather than ankle, dislocation in the absence of radiographic studies (See Pearls for a description of clinical evidence.)2
- Failed attempts at closed reduction despite optimal conditions
Anesthesia for reduction of an ankle fracture or dislocation is usually performed by methods of procedural sedation, if the reduction is not taking place in the operating room under general anesthesia. Regional ankle blocks should not be attempted because of the difficulty in application in the context of distorted ankle anatomy and the subsequent loss of a reliable neurological examination.
If possible, one physician should be responsible only for the procedural sedation and should not take part in the reduction attempt but, rather, ensure that sedation and hemodynamics remain optimal. For more information, see Procedural Sedation.
- Oxygen supply
- Bag-valve mask
- Oxygen saturation monitor
- Wall suction, suction tubing, and Yankauer suction catheter
- Intravenous catheter (>20 ga)
- Medications as needed for procedural sedation
- Normal saline (0.9% NaCl)
- Rolls of 4-in Webril, 3-4
- Stockinette, 5 in
- Rolls of 6-in plaster, 2-3
- Rolls of 4-in elastic bandage (eg, Ace wrap)
Because of the application of procedural sedation, ankle reduction is usually performed with the patient in the supine position to provide immediate access to the patient's airway for bag-mask ventilation, if needed. The reduction is performed with the ipsilateral knee in a position of flexion, thus relieving tension on the Achilles tendon and making reduction easier. Proper positioning can be accomplished through the following steps: - Bring the patient toward the foot of the bed until the knee hangs off in a flexed position. The reduction must then be performed with the physician sitting at the foot of the bed at the patient's feet.
- Have an assistant grasp the ipsilateral leg at the proximal tibia and fibula and bring the knee and hip into a position of flexion. This requires the assistant to hold the leg in this position for the duration of the reduction. The patient may be turned slightly on his or her side so that the ipsilateral leg is not held straight into the air but, rather, is braced against the bed in a position of flexion.
- Obtain and document a thorough preprocedure history, including a history of prior injuries and surgeries, the mechanism of trauma, the amount of time that has elapsed since the traumatic event, a description of the presenting symptoms, prior medical allergies and reactions, any subjective loss of strength or sensation, and the patient’s age in reference to skeletal maturity.
- Perform and document a thorough physical examination, noting ecchymoses, swelling, pallor, abrasions, lacerations, paresthesias, weakness, notable deformities of the ankle or foot, presence and character of the dorsalis pedis and posterior tibial pulses, the exact position in which the ankle and distal foot are held, and a comparison examination of the contralateral ankle. Emphasis should be placed on assessing the neurovascular status of the distal foot. Carefully explore all areas of skin overlying the ankle joint for dermal compromise that may make the injury an open dislocation.
- If the ankle injury is associated with lacerations of the skin in the area of the ankle joint, the injury is likely an open injury; tetanus prophylaxis and antibiotic coverage of skin flora should be given.
- Assess the patient for additional injuries, particularly life-threatening injuries that may have resulted from the high-force trauma that caused the ankle dislocation. Follow Advanced Trauma Life Support (ATLS) protocols, when deemed appropriate. Continue management of the ankle dislocation as soon as proper evaluation and resuscitation of the patient have insured hemodynamic stability.
- Obtain radiographs of the patient's ankle, choosing the type of radiograph that may be performed and evaluated in the shortest duration of time. Prereduction films are often a valuable source of information; however, if significant neurovascular compromise is present and radiography would delay the time until reduction can be attempted, prereduction films do not have to be obtained. Choices of radiographic techniques include the following:
- Anteroposterior (AP) and lateral views of the ankle are the most common and efficient means of radiographic assessment. These 2 views usually provide an excellent depiction of the direction of the dislocated talus and show the presence of most associated fractures. Additional views add little to the initial evaluation of the dislocated ankle and are usually more appropriate in the postreduction setting.
- A CT scan of the ankle, while superior to flat plate radiographs in revealing small fracture fragments, is usually not the test of choice since it cannot be performed portably and may delay the time to reduction. Such a test should only be considered if neurovascular compromise is not present and the scan can be quickly performed and evaluated.
- Explain the procedure, benefits, risks, alternatives, and complications to the patient or the patient’s representative and obtain signed informed consent for both the procedure and sedation. Ask the patient or the patient’s representative if he or she would like others to be present for the procedure.
- Prepare for and perform procedural sedation as described in Anesthesia.
- Position the patient as described in Positioning.
- Posterior talus dislocations are reduced by performing the following steps:
- First, hold the foot in a position of plantar flexion, thus recreating the position of the initial injury.
- Second, apply axial traction to the ankle by having an assistant grasp the distal foot and provide constant force to fatigue the musculature of the extremity.
- Third, grasp the distal tibia with one hand and create posterior traction proximal to the dislocation. At the same time, place the other hand on the posterior heel of the foot, distal to the injury, and create persistent anterior pressure. This maneuver effects reduction after a few moments.
Ankle posterior.
- Anterior talus dislocations are reduced by performing the following steps:
- First, hold the foot in a position of plantar flexion, thus recreating the position of the initial injury.
- Second, apply axial traction to the ankle by having an assistant grasp the distal foot and provide constant force to fatigue the musculature of the extremity.
- Third, while anterior traction is being applied to the distal tibia, grasp the foot at a point distal to the injury and create both axial traction and a posterior force. This posterior pressure effects reduction after a few moments.
Ankle anterior.
- Lateral talus dislocations are reduced by performing the following steps:
- First, hold the foot in a position of plantar flexion, thus recreating the position of the initial injury.
- Second, apply axial traction to the ankle by having an assistant grasp the distal foot and provide constant force to fatigue the musculature of the extremity.
- Third, grasp the distal tibia with one hand and create lateral traction proximal to the dislocation. At the same time, place the other hand on the posterior heel of the foot, distal to the injury, and create persistent medial pressure. This maneuver effects reduction after a few moments.
- Medial talus dislocations are reduced by performing the following steps:
- First, hold the foot in a position of plantar flexion, thus recreating the position of the initial injury.
- Second, apply axial traction to the ankle by having an assistant grasp the distal foot and provide constant force to fatigue the musculature of the extremity.
- Third, grasp the distal tibia with one hand and create medial traction proximal to the dislocation. At the same time, place the other hand on the posterior heel of the foot, distal to the injury, and create persistent lateral pressure. This maneuver effects reduction after a few moments.
- After each reduction attempt, repeat the neurovascular examination to ensure that blood flow has been maintained and no new sensory or motor compromise has occurred.
- If reduction has been achieved but neurovascular compromise is apparent after reduction, emergent operative management is indicated.
- If neurovascular compromise is present but reduction has not been achieved, operative management may be needed to reduce the injury, and limited future attempts should be made. If reduction cannot be accomplished after 2-3 attempts under optimal conditions, operative management should not be delayed further.
- Once reduction is achieved and the neurovascular status of the limb is stable, apply a long leg posterior splint with a sugar-tong component, which immobilizes the joint in a position of 90° of flexion. All efforts should be made to avoid applying any material that may become constricting to the ankle, since remarkable swelling may take place in the postreduction period. The distal foot and toes should be left open to allow serial neurovascular checks.
- Repeat radiography may now be attained to assess the adequacy of the reduction and document any associated fractures. Flat plate radiography may consist of repeat AP and lateral views at the minimum; a mortise or additional view may be added to further describe the condition of the joint. A CT scan of the ankle may provide additional information as to the presence of smaller fractures and the position of fracture fragments.
- Long-term orthopedic follow-up should be arranged in conjunction with the orthopedic specialist who will continue to manage this patient’s case. Many patients require surgical intervention for associated fractures of the ankle, and admission to the hospital may be needed for open fractures. If outpatient management is deemed appropriate, the patient should follow up in the next 2-3 days. Outpatient instructions should include the following:
- The patient should not bear weight on the affected ankle until instructed otherwise upon follow-up with orthopedics. The ankle should remain in the splint at all times, and instructions as to the care of the splint must be given.
- The patient should return for emergent care immediately if pain increases; if the skin color of the distal foot changes; or if any numbness, weakness, or change in temperature is experienced in the injured leg.
- The patient should understand instructions for pain medicine as deemed appropriate. Narcotics, nonsteroidal antiinflammatory drugs (NSAIDS), or both are usually warranted.
- An ankle injury with dislocation must be differentiated from a subtalar dislocation, since an attempt to reduce a subtalar dislocation with ankle reduction techniques are likely to be unsuccessful and may lead to further injury of the involved articular structures. Subtalar dislocations are rare (<2% of large joint dislocations) and are the result of high-force mechanisms of injury directed at the forefoot. The following chart compares presentations of ankle and subtalar dislocations.2
Ankle (Tibiotalar) Dislocation | Subtalar Dislocation | | Malleoli tent or perforate the skin | Talar head tents or perforates the skin | | Deformity is proximal; ankle and foot remain aligned | Deformity is more distal; ankle and foot are malaligned | | Foot is rarely held in a position of inversion or eversion | Foot is often held in a position of inversion or eversion |
- Of note, 10-20% of subtalar dislocations are irreducible by closed methods and require operative intervention. Radiographs of the ankle, including anteroposterior (AP), lateral, and mortise views, may quickly and reliably differentiate between ankle and subtalar dislocations.
- Anterior dislocations of the talus are associated with loss of a palpable dorsalis pedis pulse due to impingement from the displaced talus. This represents a vascular emergency, since the true status of the artery cannot be accurately assessed while the ankle remains dislocated.
- Use of a Doppler ultrasound may aid in establishing that some blood flow is present; however, without the presence of a palpable pulse, emergent reduction is required to restore blood flow.
- If adequate reduction cannot be achieved, or if reduction has not restored the presence of a palpable pedal pulse, emergent operative management is indicated.
- Irreducible dislocation
- Osseous fragments, capsular ligaments, and ruptured tendons, as well as foreign bodies, may all become interposed in the anatomic joint space and make closed reduction impossible.
- Repeat forceful attempts at reduction can cause additional soft tissue injury and iatrogenic fractures and can convert a closed injury into an open injury if the skin around the ankle is ruptured.
- Surgical intervention should be considered in the following scenarios:
- Failure to reduce the injury despite 2-3 attempts under optimal conditions
- Increasing tension or tenting of the skin in a closed injury during reduction attempt
- The presence of multiple other intraarticular fractures or subtalar dislocation demonstrated by radiography, in a neurovascularly intact injury
- Amputation of the foot distal to the injury
- Conversion of a closed injury to an open injury
- During closed reduction, if the skin over the ankle joint is ruptured (particularly over the malleoli), the injury has been converted into an open injury.
- Tetanus prophylaxis and antibiotic coverage of skin flora should be administered.
- If necessary, the wound should be surgically debrided.
- Rivera F, Bertone C, De Martino M, Pietrobono D, Ghisellini F. Pure dislocation of the ankle: three case reports and literature review. Clin Orthop Relat Res. Jan 2001;179-84. [Medline].
- Syed AA, Agarwal M, Dosani A, Giannoudis PV, Matthews SJ. Medial subtalar dislocation: importance of clinical diagnosis in distinguishing from other dislocations. Eur J Emerg Med. Sep 2003;10(3):232-5. [Medline].
- Crawford AH, Al-Sayyad MJ. Fractures and Dislocations of the Foot and Ankle. In: Green NE, Swiontkowski MF, eds. Skeletal Trauma in Children. 3rd ed. Philadelphia: WB Saunders Company; 2003:516-37.
- Ufberg J, McNamara R. Management of common dislocations. In: Roberts JR, Hedges JR, eds. Clinical Procedures in Emergency Medicine. 4th ed. Philadelphia: WB Saunders Company; 2004:984-6.
Joint Reduction, Ankle Dislocation excerpt Article Last Updated: Apr 8, 2008
Topic originally published: Apr 8, 2008
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