Ankle Fracture in Adults – Diagnosis and Treatment
- The ankle mortise is the articulation between the talus and the distal tibia/fibula.
- The distal tibia has 3 important parts: The medial malleolus prevents excessive inversion, the plafond (inferior roof), and the posterior malleolus contributes to joint congruency.
- The distal fibula forms the lateral malleolus, which prevents excessive eversion.
- Three ligamentous groups hold the mortise together: deltoid ligament (medial), syndesmosis (tibiofibular) and three lateral ligaments (anterior talofibular, calcaneofibular, posterior talofibular).
- Stability of the mortise is the primary determinant in fracture management.
Common Mechanisms of Injury
- Inversion injuries can disrupt the lateral ligaments, cause avulsion to the lateral malleolus or with increasing force impact the talus into the medial malleolus, causing medial malleolar fracture.
- Eversion injuries can transmit force up the fibula, causing a syndesmotic injury and/or higher fibular fracture.
- High energy significant axial loading can lead to pilon fracture (complicated fracture of the distal tibia).
History and Physical
- Palpate all ligaments thoroughly as any disruption threatens the joint stability.
- High (proximal) fibular tenderness may indicate a Maisonneuve fracture.
- Tenderness when squeezing the distal tibia/fibula together may indicate syndesmotic injury.
- Ensure the ankle is not dislocated, as fracture-dislocations need to be emergently reduced1.
- Confirm distal neurovascular status, including both posterior tibialis and dorsalis pedis pulses.
- Ensure no open fracture or skin tenting.
- Ottawa Ankle Rule indications to image.
- Inspect the mortise view for uniformity or shift = an unstable ankle.
- Medial ankle injury or proximal fibular tenderness requires imaging of the full fibula to rule out a Maisonneuve fracture1.
- Displaced or oblique malleolar fracture are usually associated with impact from the talus and should raise concern for ligamentous damage on the opposite side of the ankle.
- Pilon fractures are associated with high energy mechanisms and warrant further examination for other injuries including foot.
- In general, isolated malleolar fractures are stable if non-displaced and not associated with ligamentous injury.
- Disruption of >1 structure supporting the ankle mortise (boney or ligamentous) generally confers instability1.
- The Weber classification is useful:
- Type A fractures occur below the level of the tibiotalar joint line and spare the syndesmosis. They are generally stable.
- Type B fractures occur at the level of the tibiotalar joint and may involve the syndesmosis, thus have variable stability. The presence of concomitant medial ankle damage makes syndesmotic involvement more likely.
- Type C fractures occur above the tibiotalar joint and very often involve syndesmotic injury, making them unstable.
- Ankle injury involving syndesmotic damage may lead to a proximal fibular fracture, (Maisonneuve fracture) = unstable.
- Medial ankle injury should raise concern for concomitant deltoid ligament injury via an eversion mechanism = unstable.
- Posterior malleolar fractures are often not isolated2 and should raise suspicion for concomitant ankle damage.
- Acute: open fractures/skin tenting, neurovascular compromise, fracture dislocations (following immediate reduction), any gross instability or deformity.
- Urgent outpatient referral:
- unstable injuries, displacement, loss of joint congruency.
- Consider for all medial malleolar fractures to ensure joint and syndesmotic stability1.
- Consider for any posterior malleolar fractures involving >25% of the articular surface2. Timing is often within 24-48 hours, although practice variation may exist.
- Consider consult for all other ankle fractures within 1 week.
- Ice and elevation above the knee over the first 48 hours. Address pain.
- Reduce any acute dislocation or displacement. Pre-reduction x-rays are helpful but should not impede reduction when neurovascular status is compromised.
- If acute orthopedic consultation is required, keep immobilized and non-weight bearing.
- All immobilizations should be done at 90o to avoid Achilles shortening.
- Fractures requiring acute or urgent orthopedic consult should be immobilized while awaiting assessment. Posterior or sugar tong splints are commonly used.
- Short leg cast or walking boots are commonly used for definitive management of stable fractures.
- Always confirm neurovascular status after immobilization.
- Strict non-weightbearing is required if unstable. Stable injuries may weight bear as tolerated. If in doubt consult orthopedics.
Definitive Non-Operative Management for Stable Uncomplicated Injuries
- Most ankle fractures should receive orthopedic follow-up as there is a lack of evidence delineating the benefit of surgical -vs- conservative management of many fracture patterns3.
- Some stable and uncomplicated fractures may be managed by primary care physicians, depending on regional practice and referral patterns.
- Small, isolated avulsion tip fractures of the lateral or medial malleoli may be considered on the spectrum of ankle sprain and treated as such1.
- Truly isolated, non-displaced malleolar fractures not associated with ligamentous damage may be immobilized until clinically healed (4-6 weeks on average).
- Discuss red flags indicative of neurovascular compromise that should prompt return to the ED.
- Consider ortho follow up for all ankle fractures.
- Follow up with primary care physician at 1-2 weeks to ensure integrity of immobilization and patient compliance. Repeat imaging should be completed to confirm adequate alignment.
- Uncommon in isolated, stable injuries.
- Precise alignment of the ankle is required to retain normal biomechanics and avoid subsequent degenerative changes. Instability, displacement, comminution, and articular involvement are risk factors for poor function and require orthopedic referral.
Quality Of Evidence?
We are highly confident that the true effect lies close to that of the estimate of the effect. There is a wide range of studies included in the analyses with no major limitations, there is little variation between studies, and the summary estimate has a narrow confidence interval.
We consider that the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. There are only a few studies and some have limitations but not major flaws, there are some variations between studies, or the confidence interval of the summary estimate is wide.
When the true effect may be substantially different from the estimate of the effect. The studies have major flaws, there is important variations between studies, of the confidence interval of the summary estimate is very wide.
Significant practice variation exists, and many aspects of definitive management remain controversial.
Walls RM, Hockberger RS, Gausche-Hill M, Erickson TB, Wilcox SR. Ankle and Foot Injuries. In: Rosen’s emergency medicine: Concepts and clinical practice. 10th ed. Philadelphia, PA: Elsevier; 2023.
Odak S, Ahluwalia R, Unnikrishnan P, et al. Management of Posterior Malleolar Fractures: A Systematic Review. J Foot Ankle Surg 2016; 55:140.
Donken CC, Al-Khateeb H, Verhofstad MH, van Laarhoven CJ. Surgical versus conservative interventions for treating ankle fractures in adults. Cochrane Database Syst Rev 2012; :CD008470.
Eiff, M., Hatch, R., & Higgins, M. Ankle Fractures. In: Fracture Management for Primary Care and Emergency Medicine. 4th ed. Philadelphia, PA: Elsevier; 2020
The purpose of this document is to provide health care professionals with key facts and recommendations for the diagnosis and treatment of patients in the emergency department. This summary was produced by Emergency Care BC (formerly the BC Emergency Medicine Network) and uses the best available knowledge at the time of publication. However, healthcare professionals should continue to use their own judgment and take into consideration context, resources and other relevant factors. Emergency Care BC is not liable for any damages, claims, liabilities, costs or obligations arising from the use of this document including loss or damages arising from any claims made by a third party. Emergency Care BC also assumes no responsibility or liability for changes made to this document without its consent.
Last Updated Feb 08, 2023
Visit our website at https://emergencycarebc.ca
Add public comment…