Supination refers to a movement of the extremities that is part of running, jumping and other movements. If it is performed correctly, the affected person cannot be harmed. However, if the outward rotation occurs at the wrong time, takes too long, or if the runner has no control over the rotation, the foot, for example, will buckle outward and can cause serious injury. Athletes with excessive supination have an ineffective running style because the main load during foot roll-off is then on the outer toes, resulting in insufficient cushioning.
What is supination?
Supination means “turned away position.” Supination means “turned away position” and in arm supination refers to a movement sequence with the forearm and hand bent, in which the palm is turned upwards so that the thumb points outwards. The ulna and radius are then parallel to each other. The forearm muscles located on the radius and ulna, such as the outward rotator (supinator) and the brachioradialis muscle, are involved in the rotational movement. The joints stressed in this process are the proximal and distal radius-elbow joints. When supination is performed with the arm hanging, the palm is moved forward. In foot supination, the outer instep is pressed downward instead of inward so that the foot rolls over its outer edge. In doing so, the inside of the foot is directed upward. The heel remains in its normal position. The big toe is curved. The most important muscles involved in foot supination are called the twin calf muscle and the clod muscle. In addition, the posterior and anterior tibial muscles, the long big toe flexor and the long toe flexor also participate in the movement. The joints involved are called articulatio subtalaris and articulatio talocalcaneonavicularis. Supination also refers to the excessive outward rotational movement of the foot and hand. The malposition is also called under-pronation. About 2 to 10 percent of runners and joggers have more or less pronounced supination. Anyone who is not sure whether they are executing the movement correctly when running should occasionally examine the soles of their shoes: if the outer edges and the ball of the foot are badly worn, the person concerned is suffering from excessive supination. There are also cases of supination where only one foot is affected.
Function and task
When supination is performed correctly, it is a normal arm or foot movement that can be integrated into other more complex movements. Excessive supination or under-pronation, however, can sometimes have dire consequences for the affected individual. In running, supination consists of three partial movements: plantar flexion, inversion and adduction. In plantar flexion, the tip of the foot points downward; in inversion, the arch of the foot is lifted and pressed downward with the outside. Adduction means that the toe of the foot is turned inward. If the runner performs a jump, he or she lands on the ground with the outer edge of the longitudinal arch, and the jump is insufficiently cushioned. The lack of cushioning is passed on to all the joints, with varying effects depending on body weight. In order not to worsen the condition, prevent premature fatigue and possible injuries and accidents, it is recommended to buy the right running shoe in time. For lighter cases of supination, a neutral shoe with good cushioning is suitable. The latter is particularly important, as it must replace the missing natural cushioning. Neutral shoes are actually designed for runners with a normal rolling motion, but they can also be used by users with excessive supination if they do not have pronation support. They should be cut on curved lasts, have a reinforced toe area and good lateral guidance. For better support, it is also recommended to buy only a model with a sturdy upper. If supination is more pronounced, a special cushioning shoe is required.
Diseases and complaints
Excessive supination usually occurs together with hollow foot and markedly rigid arch. Under-pronation may be congenital or acquired during life. In combination with bow legs, unequal lower leg musculature, or familial clustering, it is congenital. An extreme example of supination is the genetically determined clubfoot, in which excessive supination occurs together with pointed foot, hollow foot and other deformities.In addition, the deformity may be caused by previous ankle injuries that are compensated for with a protective posture. Foot-muscle paralysis, damaged nerves, ligament weakness and pressure points on the ball of the foot and toes associated with pain can also lead to cramping and supination. Under-pronation puts extreme stress on the ankle joints themselves and their outer ligaments: If you twist your ankle severely, they become overstretched and can even tear (torn ligaments). Sprained ankles can also be the result. The hip joint, spine and knee are also overstressed without additional cushioning. Excessively loaded shins can fracture, or periosteum inflammation and shin splint syndrome can result. Excessive supination can also bring inflamed Achilles tendons, problems with the meniscus and supination trauma. This is a serious injury caused by overstretching of tendons, ligaments and the ankle capsule. Hollow foot and supination, if not too severe, can also be corrected with foot gymnastics, frequent barefoot walking and the appropriate footwear. If these measures do not help to strengthen the foot muscles, the only option left for the affected person is surgical correction of the hollow foot.
