Ankle sprains are one of the most common sports injuries .almost million people are evaluated each year for ankle sprain and account for 25% of all Sports related. Over all, incidence of Ankle sprain is 2.15 per 1000 person –year and is highest in the 15 to 19 age group. It is the term used for ligament injuries of the ankle. Commonly, it is an inversion injury, and the Lateral collateral ligament is sprained. Sometimes, an Eversion force may result in a sprain of the medial collateral ligament of the ankle.
The patient gives history of a twisting injury to the ankle followed by pain and swelling over the injured ligament. Weight bearing gives rise to excruciating pain. In cases with complete tears, patient gives a history of feeling of something tearing at the time of injury.
There may be swelling and tenderness localised to the site of the torn ligament .if a torn ligament is subjected to stress by the following manoeuvres, the patient experiences severe pain.
Inversion of a planter-flexed foot for anterior Talo-fibular ligament sprain.
Inversion in neutral position for complete Lateral collateral ligament sprain.
Eversion in neutral position for medial collateral ligament sprain
X-ray of the ankle (AP AND LAT.) are usually normal. In some cases, stress x-ray may be done to judge the severity of the sprain. A tilt of the talus greater than 20° on forced inversion or eversion indicates a complete tear of the lateral or medial collateral ligament respectively?
The bones forming the ankle joint are a frequent site of injury. A large variety of bending and twisting forces result in a number of fractures and fracture-dislocation at this joint. All these injuries are sometimes grouped under a general title pott s fracture
The ankle joint is a modified hinge joint .the socket is formed by the distal articular surfaces of the tibia and fibula, the intervening tibio-fibular ligament and the articular surface of the malleoli. These together constitute the ankle–mortis. The superior articular surface of the talus (dome) articulates with this socket.
The strong tibio-fibular syndesmosis, along with the medial and lateral malleoli makes the ankle a strong and stable articulation therefore, pure dislocation of the ankle is rare. Commonly, dislocation occurs only with fractures of the malleoli. The elongated posterior part of the distal articular surface of the tibia, often termed as posterior malleolus gets chipped –off in some ankle injuries.
Ligaments of the Ankle
The ankle joint has two main ligaments; the medial and lateral collateral ligaments.
1) Medial collateral ligament (deltoid ligament): This is a strong ligament on the medial side. It has a superficial (tibio-calcaneal) and a deep (tibio-talar) part.
2) Lateral collateral ligament: this is a week ligament and is often injured. It has three part
i) Anterior talo-fibular
ii) Calcaneo-fibular in the middle ,and
iii) Posterior talo-fibular.
Some terms used in relation to ankle injuries:
Following are some of the terms used to describe different forces the ankle may be subjected to.
a) Inversion (adduction); inward twisting of the ankle
b) Eversion (abduction); outward twisting of ankle.
c) Supintion: inversion plus adduction of the foot so that the sole faces laterally.
d) Proration: Eversion and abduction of the foot so that the sole faces medially.
e) Rotation: (external to internal): A rotator movement of the foot so that the talus is subjected to a rotator force along its vertical axis.
f) Vertical compression: A force along the long axis of the tibia.