A sprained ankle happens when you accidentally roll, twist, or turn your ankle in a way not typical of the joint's functional anatomy. Such forced action stretches or tears the rugged bands of ligaments holding the different ankle bones together and connecting them to the leg bones.

Ligaments function within their specific range of motion and stabilize joints by preventing excessive movements. When forces exceeding the normal range of action specific to a joint act upon it, it leads to sprain or tear.

A sprained ankle most often involves injuries to the ligaments present on the outer side of the ankle. About 85% of ankle sprains occur in the lateral ligaments.

Ankle sprains are the most common sports injuries, with indoor sports sharing most of the burden of the subject injury. Basketball players are at the highest risk of sustaining an ankle injury with a recurrence rate of more than 70%.

It may take several weeks to months for a sprained ankle to heal and recover, depending upon the severity of the injury. Appropriate care and timely management are essential for speedy and apt recovery and healing.

Anatomy

The ankle joint is made of three bones:

• Tibia
• Fibula
• Talus

There are several significant ligaments in the ankle holding the joint together;

There are three ligaments on the outer or lateral side of the ankle that make up the lateral ligament complex. These include;

• The anterior talofibular ligament (ATFL), connecting the front of the talus bone to the fibula, a long bone in the lower leg.
• The calcaneofibular ligament (CFL) connects the calcaneus, or heel bone, to the fibula, the leg bone.
• The posterior talofibular ligament (PTFL) connects the rear or posterior side of the talus bone to the fibula.
• The deltoid ligament is a thick ligament supporting the entire medial side of the ankle on the inner side.
• The anterior inferior tibiofibular ligament (AITFL) connecting the leg bones, tibia, and fibula.
• Two posterior fibular ligaments, which are arranged in a crisscross manner at the back of the tibia and fibula
• The posterior inferior tibiofibular ligament (PITFL)
• The transverse ligament
• The interosseous ligament lies between the leg bones, the tibia, and the fibula running the entire length of the two bones, from the ankle to the knee.

Of the lateral ankle ligaments, the anterior talofibular ligament (ATFL) is the most frequently damaged.

The medial side of the ankle, deltoid ligament, posterior tibiotalar, tibiocalcaneal, tibionavicular, and anterior tibiotalar ligaments are injured with forceful pronation and rotation movements of the back of the foot.

A high-ankle sprain affecting the distal tibio-fibular syndesmosis occurs when the leg is externally rotated simultaneously with the dorsiflexion of the ankle.

Causes of a sprained ankle

The twisting or rolling action of the foot forces the ankle joint out of its normal alignment. Sudden unexpected inwards twist causes one or more ligaments around the ankle to stretch or tear, resulting in a sprained ankle.

Ankle sprains can happen to people of all ages. Still, people participating in sports, walking or running on uneven surfaces, or wearing inappropriate footwear can all cause this type of injury.

Some common causes of sprained ankle include;

• A fall on a hard surface causes a twist of your ankle
• A clumsy and uncontrolled landing on your foot after jumping or pivoting
• Walking, running, or exercising on an uneven surface
• Contact injury due to accidental stepping or landing of another person on your foot

Some predisposing factors increase the risk of a sprained ankle, including;

• Participation in sports activities that require jumping, cutting action, or rolling or twisting of the foot. For example, basketball, tennis, football, soccer, and trail running.
• Walking or running on uneven surfaces or playing on poor field conditions
• A previous history of an ankle injury
• Poor physical fitness levels with weak or inflexible muscles in the ankles
• Improper gear as ill-fitted sports shoes

Symptoms of a sprained ankle

A sprain in the ankle presents as;

• Swelling around the joint
• Tenderness on touch
• Bruising of the affected joint
• Pain at rest or on movement
• Inability to walk or put weight on the affected ankle
• Skin discoloration over the affected joint
• Stiffness
• A popping sound at the impact of injury
• Restricted range of motion
• Instability of the ankle

Depending on the severity of the injury, there are three grades of an ankle sprain;

Grade 1 Sprain (Mild)

• Micro-tears cause mild stretching of the ligaments
• Mild pain and tenderness
• Swelling

Grade 2 Sprain (Moderate)

• Partial tears in the joint ligaments
• Moderate pain, tenderness, and swelling around the ankle
• Abnormal laxity of the ankle joint on movement

Grade 3 Sprain (Severe)

• Complete tear of the ligament
• Significant pain, tenderness, and swelling around the ankle
• Inability to move without support

Appropriate treatment helps to manage the sprain, failing which complications may occur as;

• Chronic pain in the ankle
• Persistent joint instability
• Arthritis development of the ankle joint

Diagnosis of ankle sprain

History of presenting complaints indicates the diagnosis. Physical examination and radiological findings confirm the diagnosis. X-rays help to rule out any concomitant fractures.

CT scans and Magnetic resonance imaging (MRI) gives detailed insight into the soft internal structures of the ankle, including ligaments.

Treatment of ankle sprains

An ankle sprain is mild in most cases and completely heals with proper treatment. Recovery time depends on the severity of the sprain, often taking few weeks to heal while severe cases recover in months fully.

Ankle sprains are reputed to cause lingering symptoms even after full recovery and cessation of pain and swelling.  

1.  Immediately after an injury to few days

1. RICER

Post-injury, immediate cessation of activity, and rest are vital to prevent further damage. Initially, apply ice for 20 to 30 minutes at least three to four times on the first day. Afterward, ice application every three to four hours for the next two days suffice.

Ice application should be used with caution in patients with vascular disease, diabetes, or nerve disturbances.

The use of elastic bandages helps to manage swelling, however, do not wrap too tightly. Wearing a brace also keeps the joint immobile. Use crutches in case of severe sprains to avoid loading the joint. Keep your foot elevated and take plenty of rest.

Sports tape, cast, or walking boots may be required depending on the severity of the injury.

• Medication

Over-the-counter pain medication should be taken to relieve pain. Corticosteroid injections should be reserved as a last resort owing to their side effects.

• TENS

For ankle sprains, place the electrodes of the TENS device on the calf and the lateral side of the ankle. TENS therapy helps to reduce pain, alleviate inflammation, and speed up recovery.

• SURGERY

Ankle sprains rarely require surgery. Severe injury to the ligaments and instability of the joint merit surgery. Surgery may be done via;

• Arthroscopic surgery
• Reconstruction surgery
• After few weeks

• Massage

Massage techniques for ankle sprain include;

• Acupressure
• Frictions
• Skin rolling
• Trigger pointing

Massage improves circulation, enhances the removal of waste, and speeds up healing and recovery. Sports massage for the ankle helps to alleviate acute and chronic lingering pain of ankle sprains.

• Therapeutic ultrasound

Therapeutic ultrasound adjuncts the function of other conservative and rehabilitative remedies for ankle sprain and reduces the total time taken for recovery.

• Active rehabilitation

Physical therapy improves range of motion, strength, flexibility, and stability.

Balance and stability training to retrain the ankle muscles are particularly important to support the joint and prevent recurrent sprains.

Some rehab exercises for ankle sprain include;

Knee motion

This exercise is an ankle range of motion exercise. The simple move stretches and relaxes the ligament of the ankle joint.

• Sit in a chair.
• Keep your foot flat on the floor.
• Start to move your knee from side to side slowly.  

Towel stretch

• Sit on the floor with your leg extended and stretched out in front.
• Wrap a towel around the ball of your foot.
• Gently pull the towel to move your toe and hold the stretch.
• Hold the stretch for few seconds without overdoing it.
• A mild to moderate stretch on your calf muscle is felt.

One-leg balance

Take support by placing your hands on a wall or the back of a chair. 

• Lift your healthy leg behind you.
• Shift your body weight onto the affected leg. 
• Try to hold the position for half a minute. You should not have any pain in your affected ankle.
• As you heal and recover, try to balance your leg without any support from a wall or chair to increase the load and strengthen your calf muscles and tendons.

Prevention

Ankle sprains have a high incidence of recurrence, so some preventive tips for avoiding the injury include;

• Keep your ankle wrapped in an elastic bandage while doing exercise or playing sports.
• Wear an ankle brace or K-tape if the previous history of sprain is there
• Adopt strengthening exercises for calf muscles
• Avoid wearing high heels and ill-fitted shoes
• Do proper warm-up before exercising
• Slow down your pace or stop activities if fatigued  
• Be mindful of the walking surface and careful when walking, running, or working on an uneven surface
• Practice stability training via balance exercises