Sudden ankle inversion or eversion can cause the ligaments to break. The ligament rupture leads to a sprained ankle. Here all its information.
An ankle sprain typically occurs after a sudden twist of the foot, usually when playing sports, hiking, or jogging. However, it can also happen when taking a bad step while doing routine daily activities. This sudden twisting movement causes an injury to one or several ligaments in the ankle joint; it then leads to swelling, pain, and a certain degree of (temporary) loss of articular function.
An ankle sprain is one of the most common consultancies in sports medicine and emergency medicine. Rough estimates suggest that sprained ankle represents more than 30% of all sports injuries, making it an incredibly common pathology. Other statistics reveal that sprained ankle is also the most common type of musculoskeletal injury in primary care. Even the U.S army recognizes ankle sprain as one of the most common injuries seen in soldiers.
Ankle spraining is obviously more common in some sports than others (heads up, it is not very frequent in golf). Basketball is the sport in which ankle sprains are more frequent, followed by soccer and volleyball. Some studies also reveal that ankle spraining seems to be more frequent in females than in males.
What is an ankle sprain?
The formal definition of an ankle sprain is a musculoskeletal lesion of the ankle. The ligaments in the ankle joint are partially or completely torn due to sudden stretching. Partial tears retain certain stability of the joint, while complete tears lose the stability of the joint. The severity and management of the injury depend on the degree of the tear.
How is the ankle joint composed?
In simple terms, the ankle is just the place where the leg meets the foot. The three main bones that form the joint are the talus (in the foot) and the tibia and fibula (in the lower leg). These bones are joined together thanks to 4 ligaments:
- The deltoid ligament: The strongest ligament actually consists of four ligaments that form a triangle that connects the tibia to three different bones in the foot (the navicular, the calcaneus, and the talus).
- The anterior talofibular ligament: Connects the fibula to the talus.
- The posterior talofibular ligament: Connects the fibula to the talus.
- The calcaneofibular ligament: Connects the calcaneus to the fibula.
What are the four movements of the ankle?
The ankle is (under normal conditions) able to make four main movements:
- Dorsiflexion: It is the movement of the foot in an upward direction towards the leg.
- Plantarflexion: It is the movement of the foot downwards away from the leg.
- Eversion: This is the movement of the foot away from the midline.
- Inversion: It is the movement of the foot in the direction of the midline.
These movements are limited by the ligaments that pull the joint together. If inversion, for example, is too sudden or taken to the extreme, putting too much force into the movement will cause an injury to one or more ligaments of the ankle joint.
What muscles make the ankle move?
Although they appear to be simple movements, each of the ankle’s four movements requires the synergic action of several movements to happen. Here is a list of the muscle groups involved in each movement:
- Ankle dorsiflexion and inversion: These movements occur thanks to the contraction of three muscles in the front of the lower leg. The muscles are the Tibialis anterior (attaches the tibia with the base of the big toe), the extensor digitorum longus (attaches the tibia to the small toes), and the extensor hallucis longus (attaches the fibula to the big toe).
- Plantarflexion: The muscles in charge of plantarflexing the foot are found in the leg’s posterior face. These muscles are the gastrocnemius (attaches the femur to the heel), the soleus (attaches the tibia and the fibula to the heel), tibialis posterior (attaches the tibia to the plantar face of the toes).
- Eversion: These muscles not only produce eversion but also prevent excessive inversion of the foot. These muscles are in the lateral part of the lower leg. They include the fibularis longus (formerly peroneus longus) (attaches the fibula to the inner face of the foot) and the fibularis brevis (attaches the fibula to the little toe).
What is the weakest ligament in the ankle?
The anterior talofibular ligament is the weakest ankle ligament, and therefore, the most commonly injured one. Approximately 70% of all ankle sprains affect this ligament and this ligament only. The anterior talofibular ligament is only 2 mm thick and 20 mm long. It is the most lateral ligament, that is, the ligament located in the outside part of the ankle. Its lateral position causes it to absorb most of the impact when twisting or placing the ankle in an unnatural position. After the talofibular ligament, the ankle’s weakest ligament is the calcaneofibular ligament, also due to its lateral position.
What is the difference between the mechanisms of an inversion and eversion ankle sprain?
Two mechanisms can cause a sprained ankle:
- Inversion: An inversion ankle sprain occurs when the foot twists upwards, making the ankle roll inwards. This inward rolling of the joint produces a lateral ankle sprain because these lateral ligaments (the anterior and posterior talofibular ligaments and the calcaneofibular ligaments) are the ones that normally prevent the foot from rolling inwards. The anterior talofibular ligament is the most vulnerable one, followed by the calcaneofibular ligament and then the posterior talofibular ligament.
- Eversion: An eversion ankle sprain occurs when the ankle rolls outwards. The ligament responsible for stopping the outward rotation of the ankle is the deltoid ligament. The deltoid ligament is much stronger than the lateral ligaments. This difference makes inversion sprain so much frequent than eversion sprain.
Besides eversion and eversion sprains, there is a third rare type of ankle sprain. A high ankle sprain is one in which the injury is not in any ankle ligament but in the ligament that joins the tibia and the fibula together right on top of the ankle joint. This type of ankle sprain results from a sudden upward movement of the foot, which is particularly common in high-impact sports like football or basketball. The recovery of high ankle sprains is considerably longer than that for normal ankle sprains.
What are the other differences between an inversion and eversion ankle sprain?
The main difference (besides the mechanism of injury) is that the inversion ankle sprain typically affects a lateral ligament while an eversion invariably injures the deltoid ligament. Take in mind that the deltoid ligament is very thick and strong. Therefore it takes a lot of energy and strength to injure it. For this reason, eversion ankle sprains tend to be more severe than inversion sprains. Eversion sprains usually are correlated with a fibula bone fracture known as Potts fracture. Other bones like the talus can also suffer a fracture when an eversion sprain occurs.
What is the difference between a sprain and a dislocation?
A sprain is simply an injury or a tear to a ligament or several ligaments that hold a joint together; there are many kinds of sprains such as ankle sprains (the most common type), wrist sprains, and even knee sprains. A dislocation, on the other hand, is a severe injury in which the bone slips out of the joint. While sprains can occur by doing regular activities like jogging or stepping into an uneven surface, dislocations usually require important falls or other types of blunt traumas.
Most of the time, ankle dislocation occurs with the tear or one or more ligaments and with the fracture of one or more of the bones that form the joint. An ankle dislocation looks very different from an ankle sprain. However, it has some similarities, such as swelling and redness around the joint; the key difference is the joint’s deformity. Also, ankle dislocation pain tends to be more severe than that of a simple ankle inversion sprain. In severe cases, the dislocated bone can tear through the skin.
Unlike an inversion ankle sprain, an ankle dislocation is a medical emergency that requires urgent medical care to insert the bone back into the joint. An ankle dislocation often requires emergency surgery to put the bone right into place. Even when given timely and appropriate treatment, most dislocated ankles never regain full function.
What’s the difference between a sprain and a strain?
Although both terms are regularly used interchangeably by the general population to describe any ankle injury that is not a fracture or a dislocation, there is an important difference between them. A sprain is an overstretching or tear of ligaments inside a joint. At the same time, a strain is an injury (overstretching or tearing) of a tendon or a muscle. The difference between a tendon and a ligament is that ligaments attach a bone to another bone. In contrast, a tendon attaches muscles to bones.
The ankle joint is the most common location for sprains, followed by the thumb, the wrist, and the knee. Strains, on the other hand, are more common in the hamstring muscle and the lower back. The two conditions’ symptoms are very similar, which causes many people to mistake the two of them. The key difference, besides location, is that while a sprain causes bruising, the cardinal symptom of a sprain is muscle spasm. The treatment for both conditions is pretty much the same.
What are the symptoms of an ankle sprain?
Common symptoms of ankle spraining include the following:
- Swelling of the joint
- Tenderness at touch
- Pain when applying weight on the joint
- Skin discoloration
It is important to note that, unlike people with fractures or dislocations, sprain patients can almost always walk (with some difficulty). Some experts affirm that walking on the affected foot practically rules out the possibility of a fracture. The sensation of a cool foot or a tingling sensation is an alarming symptom that points towards a more serious condition. The maximal tenderness points for most sprains are in the lateral (outside) part of the ankle.
How is an ankle sprain diagnosed?
The key to ankle sprained diagnosis is a thorough physical examination by your physician accompanied by a history of foot inversion suggestive of an inversion ankle sprain. Physical examination of a suspected ankle sprain involves doing several maneuvers to assess joint stability. These maneuvers include:
- Anterior drawer test: This test evaluates the integrity of the anterior talofibular ligament. The test consists of pulling the heel forward while the foot is in plantar flexion. The doctor will do the test in both the injured foot and the healthy foot for comparison. In a foot with a broken ligament, the injured foot is more movable than the healthy foot.
- Talar tilt test: This test consists of tilting the ankle sideways, both in the injured foot and in the healthy foot. Suppose there is no firm endpoint to the injured foot’s movement compared to the healthy food. In that case, the calcaneofibular ligament is likely injured.
- External rotation test: The idea of this test is to rule out a high ankle sprain. It consists of rotating the ankle away from the body while the foot is in dorsiflexion. The test is positive (indicative of a high ankle sprain) when the movement causes pain in the lower leg’s front.
- Squeeze test: This test helps rule out high ankle sprain as well as a fibular fracture. As its name implies, the test consists of the examiner putting his toe over the tibia and his other fingers over the fibula and then squeezing them together. If the patient feels pain running down the fibula’s surface in the lower leg, a fibular fracture or a high ankle sprain, or both are likely.
What imaging tests are required for an ankle sprain?
The first (and often only) imaging test the doctor in the emergency room will order is a plain foot or ankle radiograph. It is impossible to see an ankle sprain in a plain radiograph because soft tissues like ligaments or tendons are not observable in simple radiographs. However, X-rays are very useful to rule out dislocations and fractures, which are the ED doctor’s main concern.
Not so long ago, a group of doctors in the emergency department of an important hospital in Ottawa, Canada, noticed that doctors tended to order x-rays for every ankle injury that came in the ER. They also noticed that most of these X-rays showed no alterations in the great majority of cases. For this reason, they developed the so-called Ottawa rules to avoid performing unnecessary X-rays.
According to the Ottawa rules, an ankle x-ray is only necessary if there is any pain in the lateral malleolus or the medial malleolus (the bony prominences on each side of the ankle) and at least one of the following:
- Bone tenderness in the six lower centimeters of the tibia
- Bone tenderness in the six lower centimeters of the fibula
- Inability to bear weight in the affected foot after four steps
A foot X-ray is only required if there is a pain in the midfoot zone and at least one of the following:
- Bone tenderness at the base of the fifth metatarsal (the base of the small toe)
- Bone tenderness in the navicular bone
- Inability to bear weight in the affected foot after four steps
What cases require more advanced studies?
Advanced studies such as magnetic resonance imaging (MRI) or computed tomography (CT scan) are not required in most cases. However, there are some exceptions.
An MRI might be necessary if the doctor suspects a high ankle sprain or damage to the articular cartilage. If the patient has recurrent ankle sprains, an MRI scan might help locate a predisposing lesion that increases sprains’ frequency. However, a recent study revealed that approximately 30% of healthy asymptomatic individuals present ligament or joint abnormalities in their MRIs. CT scans are useful to evaluate any fractures associated with the sprain.
What are the grades of ankle sprains?
Depending on their severity, doctors classify ankle sprains into the three following grades:
- First Grade: Grade 1 ankle sprains have only microscopic tearing of the ligament. These patients present with very little swelling, little functional loss, and minimal joint instability. Patients with grade I sprain can bear weight and walk almost normally.
- Second Grade: In these cases, there is macroscopic tearing but without complete rupture of the ligament. These patients experience moderate to severe swelling as well as some small red spots called ecchymosis. These patients have moderate function loss and have more difficulty bearing weight on the affected foot.
- Third Grade: Here, there is a complete rupture of the ligament. There is severe swelling, ecchymosis, pain, and inability to bear weight without suffering insufferable pain. There is severe instability of the joint. Concomitant fractures are frequent in these cases.
Doctors differentiate between the different spraining degrees based on physical examination, basically by observing the degree of swelling and ecchymosis, the degree of functional loss, and the capacity to bear weight on the affected foot.
Tests like the anterior drawer test add valuable information about the stability of the joint. Imaging tests like MRIs or CT scans add little to no valuable information for ankle sprain staging. These staging rules do not apply to sprains that involve two or more ligaments.
What is chronic instability?
Studies show that more than 40% of ankle sprains produce residual symptoms six months after the initial injury. At least 20% of these cases represent chronic instability.
Chronic instability is a clinical term that refers to the occurrence of frequent, repetitive sprains. These patients have difficulty performing regular physical activities like jogging, jumping, or even walking on uneven surfaces. Repeated ankle lesions cause more chronic instability, which in turn cause more ankle sprains, thus creating a vicious circle.
Many times, the origin of chronic ankle instability is an ankle sprain that wasn’t appropriately treated and, therefore, did not heal correctly. Every time a ligament is overstretched or breaks, the joint loses stability. Rehabilitation tries to increase muscle strength and to retrain the tissues in charge of maintaining balance.
What is the treatment for an ankle sprain?
The treatment of ankle sprains has several different objectives, which include:
- Managing pain
- Restoring the range of motion of the joint
- Regaining strength
The acronym PRICES synthetizes the conservative treatment for acute, non-complicated ankle sprains.
- P stands for protection. Some common protective devices include braces made either from Velcro or plastic and air splints. The time of use varies according to the severity of the injury, and most cases vary from 4 days to 21 days.
- R stands for relative rest. Avoiding strenuous activities that increase pain or swelling promotes tissue healing. However, some degree of ankle movements is recommended. These movements must be made in a range of motion that does not produce any pain. Studies have shown that movements within a pain-free range of motion decrease the time of recovery. Some doctors suggest their patients spelling the letters of the alphabet with their foot several times a day.
- I stand for ice. Cool temperatures in the injured joint decrease swelling, muscle spasms, and pain. Remember to never apply ice directly over your skin. The best choice is to wrap it up in a towel before using it. Most patients benefit from applying ice 15 to 20 minutes three times daily.
- C stands for compression. ACE wraps, elastic ankle sleeves, and laced ankle support are valid options.
- E stands for elevation. Elevation of the injured extremity helps reducing swelling; keeping the ankle at a heart level should be enough to accomplish this.
Is immobilization good for ankle sprains?
The real answer is yes and no. Although immobilization in the acute face helps protect the weakened joint, prolonged immobilization leads to muscle atrophy and loss of joint functionality. For this reason, casts are contraindicated in ankle sprains, and limited immobilization techniques such as ankle bracing are the treatment of choice for ankle sprains.
Ankle taping seemed to have similar efficacy when compared to ankle bracing. However, there is an important loss of efficacy after just 24 minutes of activity, and other studies show that ankle taping becomes virtually ineffective after 40 minutes of activity. Ankle taping appears not to have any efficacy in individuals with chronic ankle instability. Furthermore, the efficacy of ankle taping is significantly dependent on the person’s ability that does the taping. Patients that do not have access to an experienced physical therapist or a certified athletic trainer may find an ankle brace easier to use and more effective.
Is it bad to walk on a sprained ankle?
In general, bearing weight on any sprained joint is a bad idea. Often, the first impulse of many (particularly if it’s their first ankle sprain) is trying to walk it off. Walking it off adds more stress to the already damaged ligaments, making the sprain worse than it was at first. Studies show that walking too soon on a sprained ankle increases recovery time and increases the risk of sequels such as chronic instability and post-traumatic arthritis.
Unfortunately, many persons with a grade I ankle sprain do not attribute much importance to it a don’t seek timely medical attention. This can lead to complications down the road, such as repeated ankle sprains in the future. Crutches during the first ten days after the injury (or more depending on the severity of the sprain) eliminate the need to bear weight on the injured ankle and decrease the risk of complications. Ankle braces also reduce the need to wear weight on the joint.
How to manage the pain in an ankle sprain?
Nowadays, the gold standard for pain management in an ankle sprain is the use of Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, ketoprofen, and diclofenac. These drugs not only reduce pain but also contribute to decreasing the swelling around the joint. For patients who suffer from NSAID allergy, acupressure has also significantly reduced pain and swelling.
What is the role of physical therapy in ankle sprain treatment?
Physical therapy and rehabilitation exercises are critical to assure full recovery and prevent reinjuries. It has three main objectives:
- Strength improvement
- Range of motion improvement
- Balance improvement
Strengthening exercises involve doing the four cardinal movements of the ankle (plantar flexion, dorsiflexion, eversion, and inversion) using elastic bands or surgical tubing as resistance. This strengthens the fibular muscles, which have vital importance in the stability of the joint.
Range of motion exercises include things like writing the alphabet with your foot several types a day and doing towel curls. Towel curls consist of placing your foot on a towel on the floor and then scrunching the towel forward with your toes and then pushing it away from you. This exercise can be done several times a day while doing other activities like sitting on the couch watching TV.
Balance and control exercises are a bit more complex. Patients must wait until they can painlessly stand on their feet. Your doctor or physical therapist will help you find the right timing for starting them. The most popular one consists of standing only on your injured foot while holding sides to the sides with your eyes open, trying to maintain balance for as much as possible (60 seconds is a good target). Once you accomplish this, you can try doing the same exercise with your arms crossed around your chest and the with your eyes closed.
Can an ankle sprain require surgery?
In the great majority of cases, surgery is not necessary and does not contribute to an overall better ankle. Still, there are a few very precise indications for surgery:
- Third-degree sprain of the talofibular ligament that causes widening of the joint
- Deltoid ligament injury
- Young athletes with athletic demands in which there is a complete tear of a ligament
When can I return to normal activities?
Your symptom duration and the damage’s degree will determine how long it takes to resume normal physical activity. Depending on the injury’s degree, it usually takes two to three weeks to return to normal. Some indicators you may be ready to exercise again include:
- Recovery of full painless range of motion of the joint
- Absence of any pain or tenderness
- The ability to balance on one leg for more than 30 s with the eyes closed
What is the prognosis of ankle sprains?
In the majority of cases that receive adequate treatment and physical therapy, the prognosis is excellent. Over 85% of patients report full recovery after six months, no matter the sprain’s grade. And after a year without symptoms, the risk of having recurrent sprains returns to pre-injury levels.
Do you feel you have symptoms of this ailment?
The tool is a Sprained Ankle Symptoms Checker. This tool gathers the most important signs, symptoms, and risk factors for it. Therefore, the tool will tell anybody who uses it the likelihood of having an ankle inversion or eversion. Using the tool is free and would only take a few minutes.