The grade-1-sprain is often called an ,enlargement of the collateral ligaments, which does not exist, because ligaments cannot be enlarged at all. Due to a supination-trauma, some fibers of one ligament are torn and appear as an enlargement. A grade-i-sprain can lead to pain as well as to tenderness and mostly slight swelling, tumefaction and haematoma, but no signs of excessive instability can be found. in a grade-2-sprain, at least one out of two or more ligaments is torn, in the case of ankle-joint sprain with damaged lateral collateral ligaments. one or two out of three ligaments are ruptured. The injury is more severe, pain and more swelling are indicators, but as in case of grade-i- sprain, tlere is no excessive or abnormal mobility of the joint.
In contrast to the grade-2-sprain, the grade-3-sprain is the stage of subluxation or partial dislocation of the joint partners. This is caused by a total rupture of its ligamentous system and large capsule tears. Major haemarthrosis and mostly excessive joint mobility can easily be seen and investigated. The joint¡¯s congruency can be destroyed. In contrast to the first two grades of sprain, when conservative treatment mostly is sufficient, a grade-3-sprain should always be operated.
Compared to the mostly involved ankle-joint, the following can be said:
In more than 90% of all anide-joint sprains, the lateral collateral ligamentous system is injured.
The therefore reason is its particular anatomical situation: In plantar fiexion the ankle shows a physiological instability with a slight incongruence (gap) of the ankle joint partners on the lateral side. Besides, the pronator muscles are weaker than the supinators, and, last but not least, the motion-pattern of supinationlinversion is greater than that of pronationleversion.
More than 90% of the lateral ankle-sprains are fresh traumas, 70% occur during competitions. In more than 90%, the anterior ligament (the anterior talo-fibular ligament) is torn, mostly alone, and in about one third together with the medial one (calcaneo-fibular ligament). So, more than 90% of the most common lateral ankle sprains belong to the group of minor traumas, where conservative treatment mostly is sufficient enough. Less than 10% of lateral ankle sprains are subluxations or complete dislocations, the grade-3- sprains, when all of the three ligaments (also the posterior talo-fihular ligament) are torn.