The mechanism of injury for the deltoid ligament is similar to ankle sprain, involving external rotation of the foot or eversion of the talus within the ankle mortise. Significant swelling, tenderness, and ecchymosis over the medial ankle, and more than 4 mm of radiological often with medial ankle injuries, while a complete tear is rare and is usually associated with ankle fractures. Injury to the deltoid ligament with injury to syndesmotic ligaments usually results in very significant ankle mortise instability. A more effective support to the injured tissues is needed and an aggressive conservative intervention should be avoided to prevent other injuries. 1.3 Biomechanics The biomechanics of the foot and ankle are important to the normal function of the lower extremity. The foot is the terminal joint in the lower kinetic chain that opposes external resistance. Proper arthrokinematic movement within the foot and ankle influences the ability of the lower limb to attenuate the forces of weight bearing. It is important for the lower extremity to distribute and dissipate compressive, tensile, shearing, and rotatory forces during the stance phase of gait. Inadequate distribution of these forces could lead to abnormal stress and the eventual breakdown of connective tissue and muscle. The combined effect of muscle, bone, ligaments, and normal foot biomechanics will result in the most efficient force attenuation in the lower limb. 16
Abnormal pronation and supination are nothing more than hyper or hypomobilities, respectively, within the joints of the foot and ankle. Excessive motion or restricted motion reduces the ability of the foot to act as a shock absorber, torque convertor, mobile adaptor to the terrain, and a rigid lever to push off from. As a result of changes in the joint mobility, connective tissue changes occur, in addition to alterations in muscle function. Giving way could occur due to greater ankle inversion and internal rotation angles during the pre-landing phase and at initial contact, because the ankle was in a less stable position. Also the giving way could happen even with typical ankle joint angles at initial contact along with delayed peroneus pre-activation. Lateral ankle sprains (LASs) are a common injury sustained by individuals who participate in recreational physical activities and sports. After LAS, a large proportion of individuals develop long-term symptoms, which contribute to the development of chronic ankle instability. 1.4 Symptoms The mechanism of rolling your ankle is a clear indicator that you are likely to have sprained your ankle. You may hear a popping or cracking sound at the time of injury The injured ligaments will be quite tender to touch in that initial phase Swelling and bruising Generalized ankle pain In the cases of a severe ankle sprain, you may have difficulty walking and may require the use of crutches to mobilize.
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- Fall '16
- MAM SAREEN
- The Land, Foot Ankle