Ankle Ligament Injuries

144 Ankle Ligament Injuries

Gwendolyn Vuurberg PhD123, J. Nienke Altink BSc123, Rover Krips MD PhD1234, and Gino M. M. J. Kerkhoffs MD PhD1234

1 Department of Orthopaedic Surgery, Academic Medical Centre, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, The Netherlands

2 Academic Center for Evidence Based Sports Medicine (ACES), Amsterdam, The Netherlands

3 Amsterdam Collaboration for Health and Safety in Sports (ACHSS), Amsterdam, The Netherlands

4 Department of Orthopaedic Surgery, Flevoziekenhuis, Almere, The Netherlands

Clinical scenario

  • During a soccer match, a 23‐year‐old male athlete suffers an inversion injury during a cutting movement while trying to pass an opponent. The ankle immediately feels swollen and painful. He has limited ability to bear weight, and is transferred to the Emergency Department.
  • According to standard protocol, the Ottawa Ankle Rules (OAR) are applied and are found positive due to pain over the lateral malleolus, and an x‐ray is taken, which is negative for a fracture.
  • Apart from visible swelling of the lateral ankle and pain on palpation, no further physical tests can be tolerated by the patient.

Relevant anatomy

Of all ankle sprains, 85% involve the lateral ankle ligaments.1 This ligament complex consists of three ligaments: the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL).2 The most common mechanism leading to lateral ligament damage is an inversion–plantarflexion–internal rotation injury of the foot. Ligament damage occurs when tension on any of the three ligaments in the ankle exceeds the extensile strength in the tissue. The maximal load to failure is lowest for the ATFL followed by the CFL. The PTFL has the highest load to failure.3 The deltoid is the primary ligament on the medial side of the ankle. Damage on the medial side of the ankle occurs less frequently and is often associated with ankle fractures. The focus of this chapter is on the lateral ankle sprains (LAS), and deltoid damage will therefore not be further discussed in this chapter.

Overall, the term ankle sprain is used to describe a variety of pathologies of the ligaments of the ankle. To classify the severity of damage to the ankle ligaments, a grading system has been developed (Table 144.1).4 As the microscopic ligament severity often does not completely capture a patient’s overall pathology, a system based on clinical symptoms only has also been introduced.5

Table 144.1 Classification system for ankle sprains and injury to lateral ligaments. Source: Adapted from Konradsen et al.4

Injury severity4 Clinical symptoms5
Grade I Microscopic injury without stretching of the ligament on macroscopic level Little swelling and tenderness, minimal or no functional loss, and no mechanical joint instability
Grade II Macroscopic stretching, but the ligament remains intact Moderate pain, swelling, and tenderness, some joint motion loss, and mild to moderate joint instability
Grade III Complete rupture of the ligament Complete ligament rupture with marked swelling, hemorrhage, and tenderness, function loss, and joint motion and instability are markedly abnormal

Top three questions

  1. In patients with acute lateral ankle injuries, does advanced imaging result in better diagnosis compared to radiographs only?
  2. In patients with lateral ankle ligament injuries, does functional support result in better outcomes compared to cast immobilization?
  3. In patients with acute injury of the lateral ligament complex, does surgical treatment lead to better outcomes compared to conservative treatment?

Question 1: In patients with acute lateral ankle injuries, does advanced imaging result in better diagnosis compared to radiographs only?


Many patients who present to the Emergency Department after sustaining an LAS mainly suffer from pain and are unable to bear weight on the affected ankle. This in combination with pain of the lateral ankle usually leads to positive OAR, and thus x‐rays are typically performed. For most patients, a fracture is then excluded. Are these rules reliable enough and are there other types of imaging that may provide more accurate diagnosis, especially in those who suffer from so much pain that it prevents full physical examination?

Clinical comment

In many patients, the pain is so severe that a thorough initial physical assessment is impossible. Reliable initial imaging techniques may help diagnose the injured tissue and decide whether early treatment is required to enable quick return to play.

Available literature and quality of the evidence

The best available evidence for this research question was mainly extracted from cohort studies and systematic reviews based on cohort studies (level II). Only two included studies had a randomized controlled trial (RCT) design (level I).


The OAR are widely used to diagnose fractures in patients who have suffered from acute ankle trauma. However, a large proportion of the radiographs are negative in patients who sustained an LAS. This raises the question whether the OAR are sufficient in patients with LAS. To compensate for the low reported specificity, the use of OAR only by an experienced nurse or physician has been proposed.6 Other clinical decision rules, such as the Bernese decision rules, have also been suggested.7 The sensitivity of these clinical decision rules, however, was too low to promote clinical use.6 Ultrasound (sensitivity 92%; specificity 64%)8,9 in the acute setting may actually do a better job of determining which patients require a radiograph,6 as it may both diagnose small foot and ankle fractures and ligament and other soft tissue injury (level III).10,11

Additional diagnostics that may provide further insights include magnetic resonance imaging (MRI) and computed tomography (CT). Despite the role of MRI in patients who require further treatment, it is costlier than other imaging modalities, its availability is limited in the acute setting,12 and it does not have an additional role in those who can be discharged without further follow‐up.13 Therefore, just as with CT scans, MRIs do not have any additional value in the acute setting (level II).7

Resolution of clinical scenario

  • If a fracture is suspected, other clinical decision rules may be used in addition to the OAR to increase specificity.
  • If available, ultrasonography can be used to provide a more reliable assessment of the extent of the injury and may be used to determine who requires a radiograph.
  • MRI and CT imaging, especially in the acute setting, are generally not indicated.

Question 2: In patients with lateral ankle ligament injuries, does functional support result in better outcomes compared to cast immobilization?


Patients that present to the Emergency Department are often unable to bear weight on their affected ankle. To provide some stability, immobilization by means of a cast may be chosen as an acute treatment method. However, this prevents early exercise, whereas taping and braces may be applied and removed by patients as needed.

Clinical comment

Lateral ankle ligament injury can be treated with plaster cast immobilization or functional supports, such as tape, elastic bandage, or brace. All options are widely used in clinical practice, which suggests either a lack of available evidence or a lack of familiarity with the evidence.

Available literature and quality of the evidence

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Nov 28, 2021 | Posted by in ORTHOPEDIC | Comments Off on Ankle Ligament Injuries

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