Posts Tagged ‘ankle sprain’
Ankle sprains are some of the most common injuries in sports. Other names for ankle sprain include twisted ankle and rolled ankle. A sprained ankle can have a limiting effect on a professional athlete’s season and on any athlete’s performance in the long term. Long term consequences of sprained ankles such as ankle instability and failed proprioception make this an important injury to know how to diagnose and treat.
An ankle sprain happens when the ankle rolls more than it can and ligaments are torn. The most common for of ankle sprain is when the lateral ankle ligaments (lateral ankle complex) are torn. This type of ankle sprain occurs when the foot rolls inward in inversion, thus tearing the outer ligaments. This means that the ligaments tying the fibula, talus and calcaneus are torn. A torn deltoid ligament (medially) or syndesmosis (known as a ‘high ankle sprain‘ – a sprain at the level between the tibia and the fibula) are also possible, but less common.
Classification of ankle sprains
Ankle sprains are classified according to their location and severity. Location of ankle sprains, as mentioned above, can be lateral (85%), high (10%) or medial (5%).
In most all ankle sprains the first ligament to be injured is the anterior talo-fibular ligament. Severity classification of ankle sprains depends on how badly the ligament has been injured and which ligaments are injured next, is as follows:
- Grade I – Partial tear of the lateral ligaemnts. The anterior-talofibular ligament is the main ligament affected. There is minimal instability on examination and anterior drawer is normal.
- Grade II – Decreased motion and stability. The anterior talo-fibular ligament is torn while the calcaneo-fibular ligament is intact but damaged. There is laxity on inversion and an anterior drawer is present.
- Grade III – The whole lateral ligamentous complex is torn (the posterior talo-fibular ligament is the last to be afflicted). This results in total loss of function, diffuse swelling, marked instability.
Because all sprains will result in swelling of the ankle, examination and primary classification of ankle sprains should be done within 72 hours.
Clinical presentation of ankle sprains
Ankle sprains are painful. The pain can be followed by swelling. The pain in ankle sprain starts of as point tenderness over the affected ligaments and structures, but quickly becomes diffuse as hemorrhage and edema move in.
Ankle sprains result in two types of ankle instability - Mechanical and functional:
- Mechanical instability can be demonstrated by taking dynamic x-rays under strain (with a machine that bends the ankle at preset angles and forces – stress views). Mechanical instability is diagnosed when there are more than 6 degrees lateral tilt or 2 mm posterior opening. Mechanical instability usually refers to instability of the subtalar joint. Mechanical instability is present when the ligaments of the subtalar joint are damaged – first the anterior talo-fibular, then the calcaneo-fibular, but also the cervical and inter-osseous ligament (bifurcate ligament) of the sinus tarsi.
- Functional instability is more difficult to measure because it is a consequence of loss of proprioception and results in functional difficulty to walk over uneven surfaces. It is the functional instability that cases recurrent ankle sprains, due to carelessness of the patients who are unaware of their problem. Functional instability is diagnosed when there is a subjective feeling of the ankle giving way or 3 or more ankle sprains withing a year.
Ankle locking is not a part of the normal symptoms of ankle sprain. If there is ankle locking a fracture in the talar dome should be suspected.
Treatment of ankle sprains
Ankle sprain treatment can be divided into conservative and surgical. In most cases surgical treatment for ankle sprains will not be oped for. In grade I and grade II ankle sprains functional treatment results in great long term results. There is controversy regarding grade III ankle sprains, however surgery is not automatic. Long non-weight baring and slow rehabilitation is also an option for grade III ankle sprains.
The goal of conservative treatment for ankle sprain is functional rehabilitation. Rehabilitation should be done with particular attention given to stability. Some exercises might be done with an ankle brace or aircast.
Conservative treatment for ankle sprains can be conceptually divided into three phases, as time elapses from the injury. During the acute phase after ankle sprain the PRICE method is used: Protection, Rest, Ice, Compression and Elevation.
In the second phase, weight bearing is begun gradually. Leg balance exercises are employed. For example, one legged hopping or standing on an uneven surface such as a surface with a ball base.
After 3-6 weeks, agility and functional drills (walking, running and jumping) are encouraged aiming for sports specific drills. The time frames mentioned here are only estimates, as a particular patient’s characteristics dictate the rate in which treatment will be done.
Indications for surgical treatment are high grade ankle sprain with instability. Regarding high ankle sprains (syndesmosis injury) specific indication for surgery include widening of the syndesmotic interval to 2 mm or more and lateral shift of the talus. Some say that medial ankle injuries such as those from pronation – external rotation are indications for surgery. In all of these cases the reduction has to be very accurate. Surgery can be augmentation or capsular stretching and reefing
