What are the Grades for Ankle Sprains?

Patient Presentation
A 19-year-old female came to to the emergency room complaining of spraining her right lateral ankle while playing basketball one hour ago. She has a history of multiple ankle sprains in the past. She was going up to catch a ball and inverted her foot after striking the foot of another player.
She states that it immediately swelled differently than previous sprains and she is unable to walk which is also unusual from her other sprains. She also says “it just feels different.”The past medical history reveals that she is otherwise a healthy active athlete.
Her review of systems shows no other injuries.
Her pertinent physical exam shows her entire right ankle is markedly swollen with the lateral > medial aspect. She is markedly tender over the anterior and lateral ligaments of the lateral ankle (i.e. anterior talofibular ligament and fibulocalcaneal ligament). She has a positive anterior drawer sign.
The radiologic evaluation showed no associated fracture.
The patient was diagnosed with a grade 3 ankle sprain of the anteriolateral ligament and grade 2 ankle sprain of the fibulocalcaneal ligament.
Her clinical course was uncomplicated. She placed ice on it and elevated her ankle at every opportunity. She was placed into an air cast immobilization device with crutches for mobility for 6 weeks. After that time, she underwent aggressive, supervised physical therapy to increase range of motion and muscle strengthening to facilitate proprioception sense in the ankle joint.
She was able to run without hesitation or pain after 5 months and was returned to sports.

Ankle injuries are one of the most common sports-related injuries. Ankle fractures are more common in young children and preadolescents because the ligaments are much stronger than the bones or growth plates in this area. Ankle sprains are more common in adolescents and adults as the reverse is true.

Ankle sprains result from force around the ankle that exceeds the tensile strength of the supporting ligaments of the ankle but less than that which breaks the ankle bones.

The ankle capsule-ligament complex has 5 primary ligaments:

  • Medial ankle – the deltoid is the strongest ligament in the ankle and has two parts:
    • Superficial deltoid ligament – runs from the medial malleolus to the calcaneus posteriorly
    • Deep deltoid ligament – runs from medial malleolus to the talus
  • Lateral ankle – these ligaments act like 3 guidewires to the lateral ankle and are generally injuried in the following order:
    • Anterior talofibular ligament – runs anteriorly to the lateral malleolus
    • Fibulocalcaneal ligament- runs laterally to the lateral malleolus
    • Posterior talofibular ligament – runs posterior to the lateral malleolus

Most ankle injuries involve an inversion of the ankle. The ability to walk generally excludes a fracture. People with third-degree ankle sprains often give a history of an audible snap.
The physical examination revels intact skin with swelling. Pain upon motion is common as is point tenderness over the ligaments. An anterior drawer sign indicates anterior talofibular ligament rupture.

Luckily most ankle sprains are self-limited and can be treated conservatively with
ice, rest, immobilization and elevation being early mainstays. Ice and elevation help to decrease the swelling and reduce the danger of long-term postswelling fibrosis.
Once acute swelling and pain are reduced, therapy to increase the range of motion should be instituted to prevent recurrence of an ankle sprain. Desired range of motion is 90 degrees plantar flexion and 10-15 degrees of dorsiflexion.
Muscle strengthening also helps. Regular walking is often all that is needed. Additionally, specific muscle strengthening and proprioreceptive exercises may be done by the patient themselves or under the direction of a physical therapist.

Surgery is indicated for complete rupture of the distal talofibular ligament. Surgery is also indicated if the deltoid ligament is entrapped in the joint itself. Surgery for anterior talofibular ligament ruptures does not improve the outcome for most patients. Surgery indications for patients with with double ruptures (i.e. anterior talofibular and fibulocalcaneal ligament ruptures) is debated.

Patients can return to sports when they have no limp, hesitation or pain. Lack of swelling in the ankle is not a good indicator of readiness to return. Protective strapping and/or supportive footwear may help reduce recurrance rates.

Learning Point
The staging of ankle sprains is:

  • Grade 1 – symptomatic stretching of the ligaments without rupture or failure of the ligament fibers
  • Grade 2 – partial rupture or failure of the ligament fibers
  • Grade 3 – complete rupture or failure of the ligament fibers

Ankle sprains are primarily staged or graded clinically. The amount of swelling and bruising and the clinical stability of the ankle determines whether the ankle ligaments are stretched without significant tear, partially torn, or completely torn.

Questions for Further Discussion
1. How useful is magnetic resonance imaging in ankle sprains?
2. What are the indications for an ankle arthrogram?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Information prescriptions for patients can be found at Pediatric Common Questions, Quick Answers for this topic: Sprains.

Fleisher GR, Ludwig S. Synopsis of Pediatric Emergency Medicine. Williams and Wilkins. Baltimore, MD. 1996:123-126.

Foster R. Acute Ankle Sprains. eMedicine.
Available from the Internet at http://www.emedicine.com/orthoped/topic373.htm (rev. 7/20/04, cited 3/28/05).

Donna M. D’Alessandro, MD
Associate Professor of Pediatrics, Children’s Hospital of Iowa

April 11, 2005