Adduction: Function, Tasks, Role & Diseases

Adduction refers to movements of a body part that are directed toward the center of the body (bracing). Adduction exists at 4 joints of the human body: the hip joint, the shoulder joint, the metacarpophalangeal joints of the fingers, and the thumb saddle joint.

What is adduction?

Basically, adduction describes moving body parts closer to the body. The term is defined in descriptive anatomy using the plane-axis system. There, movements are defined starting from the so-called zero position. This is defined for all joints by the position in the upright stand with hanging arms. Basically, adduction describes the movement of body parts towards the body, for example, the application of a previously splayed arm.

Function and task

The adduction movement has an analytical meaning for physicians or physiotherapists. By defining the movement with the amplitude, it is possible to test and document whether there is a limitation of function in case of movement disorders. In this way, strength and mobility are examined. The tests are repeated at regular intervals to check whether medical or other therapies have brought about an improvement or not. Depending on the results, the further procedure must be modified. The best known are the adductors of the thigh, which pull the leg inward over the hip joint. These are five muscles that all come from the pubic bone, pull across the hip joint, and attach to the inside of the femur and the inside of the tibia, respectively. In addition to adduction, these muscles are also involved in other movements. Most notably in flexion and external rotation. This combination of the three types of movement is often used in everyday life and in sports. In walking and running in the swing leg phase and, for example, in soccer when playing the ball with the inside of the foot. In the shoulder joint, the most powerful adductors are the pectoralis major muscle and the latissimus dorsi muscle. As in the hip joint, they combine adduction with other movements for functional range of motion. The pectoralis pulls the arm down forward from a raised position, an activity that occurs in many throwing movements and other athletic activities. For example, in volleyball during the butterfly, in handball during the throw, and in swimming especially during the butterfly in the first phase of movement after immersion. The latissimus tends to pull the arm down backwards, which occurs, for example, during pull-ups and in all swimming styles. The adductors of the fingers are located on the inside of the fingers and pull fingers 2,4 and 5 towards the middle finger in a pure adduction movement. This function occurs whenever we grasp something. Thumb adduction is actually a movement that does not occur functionally. The muscle that performs it, the adductor pollicis muscle, is involved in combination movements that bring the thumb toward the other fingers, for example, when grasping with the fingertips or the whole hand.

Diseases and complaints

The most common dysfunction of adduction involves an injury in the muscle, very often in the adductor muscles of the hip. Adductor strains or muscle fiber tears in this area are very common in sports. Strain, muscle fiber tear or muscle tear differ only in their severity. Accordingly, the symptoms that occur are similar, but of different intensity, which makes the healing phase different in time. These injuries are always accompanied by pain and a loss of function. The body switches to rest in order not to irritate the site of injury even more. For those affected, this is followed by a more or less long rest phase in the affected area, with subsequent therapy and a slow build-up of strain. As with other muscles, the adductors can also be affected by irritation in the area of the insertion tendons (insertion tendopathy). This form of irritation is a typical overuse syndrome and more frequently affects bi- or multi-joint muscles; in the hip joint the gracilis muscle, which extends over the knee joint, and in the shoulder joint the two already named. The result is pain on tightening the affected muscles and stretching them. The therapy is similar to that for strains, but the cause of the overload should always be researched in order to be able to minimize it in the long term.The tendons of origin of the hip adductors also show inflammatory reactions of this type more frequently. Due to the localization, this is referred to as osteitis pubis. Like all other movements, adduction is also affected if there is arthrosis in the associated joint. In this wear and tear disease, joint pain, loss of strength and movement restrictions occur gradually. The reduction in strength and mobility initially tends to affect movements that are performed against gravity during everyday activities. Therefore, adduction is not affected until an advanced stage. In the hip joint, this primarily has consequences for walking for people with the disease. In the shoulder joint, all movements that are performed with a weight load in the direction of the center of the body, such as eating and drinking, are affected.

are affected, such as eating and drinking.