2,000,000. It’s a huge number. It’s also the estimated number of ankle sprains sustained every year in the United States alone. One in six injuries sustained by a high school athlete will be an ankle sprain, more specifically a lateral ankle sprain, making it the most commonly occurring injury in all high school sports. While most ankle sprains heal relatively quickly, 50% of the time they account for a loss of sport participation for more than one week. As always, it is important and necessary to understand ankle anatomy before learning prevention; but first, what are the risk factors for ankle sprains and how are they graded?
- Prior Injury
- As with many injuries, prior injury is a significant risk factor for future ankle sprains, with 15.7% of all ankle sprains being that of a recurring injury in sport that involves jumping and landing.
- Think you are protecting yourself by wearing a brace? Think again! A 2013 study highlighted that athletes were wearing braces when 10.6% of ankle sprains occurred. Braces being worn included lace up, ridged frame, and neoprene sleeves.
- Play a contact sport? 42.4% of all ankle sprains occur as a result of contact with another player.
Grading Ankle Sprains
Grade I Sprain
- Slight stretching and microscopic tearing of the ligamentous fibers
- Mild tenderness and swelling around the ankle
Grade II Sprain
- Partial ligament tearing
- Moderate tenderness and swelling around the ankle
- Abnormal looseness of the ankle joint
Grade III Sprain
- Complete ligament tear
- Significant tenderness and swelling around the ankle
- Ankle instability
Fig. 1 Anatomy of the Ankle
Importance of an X-Ray
The Ottowa Ankle rules are well-established clinical guidelines used to determine the need for radiography (x-ray imagining). These rules are very good at ruling out the occurrence of an ankle fracture, if the following are not present. According to these rules, x-rays are indicated if there is pain in the malleolar zone and any of the following:
- Bone tenderness or pain to palpation of the distal 6 cm of lateral malleolus (Fig 1.)
- Bone tenderness or pain to palpation of the distal 6 cm of the posterior edge of the medial malleolus (Fig 1.)
- Inability to weight bear four steps immediately after the injury or in the ER
Bones and Ligaments
The ankle is composed of three structures: the Tibial malleolus, Fibular malleolus and Talus making up the “Mortise or Talocrural joint”. This is the principle joint of the ankle making up plantarflexion (toe pointing), and dorsiflexion (toes pulling up). With the SubTalar Joint the ankle also allows motions of Inversion (toes in), and Eversion (pinky toe pulling out). These motions are restricted by ligaments. The lateral, or outside, ligaments of the ankle joint include the Anterior TaloFibular Ligament (ATFL), which restricts inversion range of motion. It is also the most commonly injured ligament along with the CalcaneoFibular Ligament (CFL). The medial, or inside, ligament of the ankle joint is the very strong Deltoid Ligament Complex which restricts eversion range of motion. It is less often involved in ankle sprains due to its strength; however, can be affected in a traumatic inversion/ eversion ankle sprain.
The muscles of the ankle act to dynamically stabilize and protect the ankle joint to avoid injury to the ligaments mentioned above. Arguably, the most important muscles of the ankle that are involved in lateral ankle sprains are the Peroneus Longus and Peroneus Brevis. These two muscles originate at the fibula with the Peroneus Longus coursing around the posterior aspect of the lateral malleolus, underneath the foot, inserting into the first metatarsal (1st Toe). The Peroneus Brevis travels along the same path inserting into the styloid of the 5th toe. Together, these muscles stabilize the arch of the foot and act to prevent inversion range of motion.
The Anterior Tibialis muscle is another significant stabilizer of the ankle complex, originating from the lateral aspect of the tibia, and inserts into the top of the first metatarsal. Finally, the Gastrocnemius and soleus muscle originate at the backside of the tibia and fibula. Together, they insert into the Achilles tendon, which acts to plantarflex and inverts the ankle joint.
High Ankle Sprains
Fig. 2 Anatomy of the lower leg
High ankle sprains are different and typically more severe than a lateral “low” ankle sprain. High ankle sprains occur when the ankle is dorsiflexed, locking up the ankle joint, and forcefully planted on causing a twisting motion of the ankle. Due to the anatomy of the ankle, the syndesmosis (red arrow) is spread and occasionally torn. These ankle sprains involve the Tibiofibular joint’s syndesmosis (Fig. 2) and usually require increased healing time.
I know you are all wondering…
Does taping help? To sum up the research, the jury is still out on this question. Most research has found minimal evidence suggesting that ankle taping actually reduces susceptibility. Furthermore, research has actually found ankle taping to reduce proprioceptive feedback (the ability to understand where your ankle is in space) in an athlete who finds himself or herself in an unstable or abnormal position. Some research has supported the use of ankle taking by athletes who have experienced one or more ankle injuries, but it is important to understand that this should never be used as the first-line treatment for ankle injuries. Unfortunately, there is currently no recommended best practice guideline for this question.
Check out Part II in our video library for an explanation of 5 exercises to reduce the risk of ankle sprains. In conclusion, ankle bracing and or taping should not be used in place of aggressive physical therapy including strengthening, stabilization, muscle endurance training, and balance/proprioceptive training.
Swenson D, Collins C, Fields S, Comstock R. Epidemiology of US High School Sports-Related Ligamentous Ankle Injuries, 2005/06-2010-11. Clin J Sport Med 2013;23(3):190-196.
McKay GD. Ankle injuries in basketball: injury rate and risk factors. Br. J. Sports Med.2001;35:103-108.