Pronation and supination of the arm only are entirely due to the radius and ulna, with no movement at the shoulder. The opposite motion, from the palm facing backward to the palm facing forward is supination. It is important to note that at no point is there any movement at the shoulder. All of the movement is in the lower arm. In pronation the head of the radius pivots in the radial notch of the ulna, and the distal end of the radius ends up crossed over the ulna.
This is the reason why anatomical position has the palms facing forward, for in this position the radius and ulna appear parallel. Figure 7. Internal rotation sometimes called medial rotation and external rotation sometimes called lateral rotation differ from pronation and supination by the location of the rotation; unlike pronation and supination, there is no movement in the lower arm.
In medial rotation all the movement is in the shoulder, and the arm rotates so that, once again, the palm faced backward, but this time the radius and ulna don't cross. Think of that movement as rotating the arm toward the midline of the body, hence the name medial rotation.
Reverse that motion, moving the shoulder to return to anatomical position, and you have just done lateral rotation. Once again, think of rotating the arm toward the side, putting the lateral in lateral rotation. Also note that medial rotation and lateral rotation are also possible in the legs. Right rotation and left rotation of the head are fairly straightforward, as it were see Figure 7. Why do I specify right and left? I have to!
With your head being right on the midline, I can't use the words medial and lateral , now can I? Special movements are called that simply because they don't easily fit in the other categories. You can, however, divide them according to the part of the body involved. For those of you foot fetishists, let's start from the ground up, as it were. Abduction and adduction are motions of the limbs, hand, fingers, or toes in the coronal medial—lateral plane of movement.
Moving the limb or hand laterally away from the body, or spreading the fingers or toes, is abduction. Adduction brings the limb or hand toward or across the midline of the body, or brings the fingers or toes together. Circumduction is the movement of the limb, hand, or fingers in a circular pattern, using the sequential combination of flexion, adduction, extension, and abduction motions. Adduction, abduction, and circumduction take place at the shoulder, hip, wrist, metacarpophalangeal, and metatarsophalangeal joints.
Abduction and adduction motions occur within the coronal plane and involve medial-lateral motions of the limbs, fingers, toes, or thumb. Abduction moves the limb laterally away from the midline of the body, while adduction is the opposing movement that brings the limb toward the body or across the midline. For example, abduction is raising the arm at the shoulder joint, moving it laterally away from the body, while adduction brings the arm down to the side of the body.
Similarly, abduction and adduction at the wrist moves the hand away from or toward the midline of the body. Spreading the fingers or toes apart is also abduction, while bringing the fingers or toes together is adduction.
Adduction moves the thumb back to the anatomical position, next to the index finger. Abduction and adduction movements are seen at condyloid, saddle, and ball-and-socket joints see Figure 2. Circumduction is the movement of a body region in a circular manner, in which one end of the body region being moved stays relatively stationary while the other end describes a circle.
It involves the sequential combination of flexion, adduction, extension, and abduction at a joint. This type of motion is found at biaxial condyloid and saddle joints, and at multiaxial ball-and-sockets joints see Figure 2. Rotation can occur within the vertebral column, at a pivot joint, or at a ball-and-socket joint. Rotation of the neck or body is the twisting movement produced by the summation of the small rotational movements available between adjacent vertebrae.
At a pivot joint, one bone rotates in relation to another bone. This is a uniaxial joint, and thus rotation is the only motion allowed at a pivot joint. For example, at the atlantoaxial joint, the first cervical C1 vertebra atlas rotates around the dens, the upward projection from the second cervical C2 vertebra axis.
This joint allows for the radius to rotate along its length during pronation and supination movements of the forearm. Rotation can also occur at the ball-and-socket joints of the shoulder and hip. Here, the humerus and femur rotate around their long axis, which moves the anterior surface of the arm or thigh either toward or away from the midline of the body. Movement that brings the anterior surface of the limb toward the midline of the body is called medial internal rotation.
Conversely, rotation of the limb so that the anterior surface moves away from the midline is lateral external rotation see Figure 3. Be sure to distinguish medial and lateral rotation, which can only occur at the multiaxial shoulder and hip joints, from circumduction, which can occur at either biaxial or multiaxial joints. Turning of the head side to side or twisting of the body is rotation. Medial and lateral rotation of the upper limb at the shoulder or lower limb at the hip involves turning the anterior surface of the limb toward the midline of the body medial or internal rotation or away from the midline lateral or external rotation.
Supination and pronation are movements of the forearm. In the anatomical position, the upper limb is held next to the body with the palm facing forward. The elite athletes group exhibited a mean age of The mean time period over which the squash players had practiced the sport was Medial and lateral shoulder rotations, as well as the distances between the contralateral coracoid process and the cubital fossa that have been determined for each group are shown in Table 1.
Correct functioning of the glenohumeral joint requires precise coordination between the muscles of the scapula and the static stabilizers. The delicate balance between shoulder mobility and stability is what ensure since the isometric movements of daily tasks to the explosive throwing actions involved in sporting activities. Arthroscopy ;16 01 it is still not clear if there is a true association between internal impingement with the internal impact and the medial rotation deficit in subjects who practiced overhead sports.
Results of arthroscopic treatment of posterosuperior glenoid impingement in tennis players. Am J Sports Med ;30 02 The currently accepted model of the occurrence of medial rotation deficit proposes that posterior capsule contracture is the eliciting factor of the cascade of injuries that affect overhead athletes. As tightness of the posterior capsule develops in the shoulder, the glenohumeral contact point is shifted toward the posterior and superior directions when the shoulder is in abduction and lateral rotation.
The hyperangulation and hyperlateral rotation forces cause an overload of the rotator cuff leading to partial tears. Current Controversies.
Point counterpoint. Arthroscopy ;15 08 The results presented in the present paper provide an unprecedented comparison between the shoulder motion parameters of asymptomatic squash players with those established for a large and diversified population of non-athletes.
Shoulder injuries in overhead athletes. The "dead arm" revisited. Scapular position and orientation in throwing athletes. Am J Sports Med ;33 02 The definition of normal physiological parameters established in the present investigation is not only important for the identification of motion anomalies, but also for the adoption of prophylactic measures that could prevent the aggravation of GIRD and associated lesions.
Such causes might be related to the existence of medial rotation deficit together with repetitive overload of the shoulder, conditions that can be treated through rehabilitation programs. Squash, similarly to other overhead sports, causes adaptive changes that trigger glenohumeral medial rotation deficit accompanied by significant lateral rotation gain and can generate pathogenic alterations in the shoulder. Abrir menu Brasil. Revista Brasileira de Ortopedia. Abrir menu. View Full Term. By clicking sign up, you agree to receive emails from WorkplaceTesting and agree to our Terms of Use and Privacy Policy.
By clicking sign up, you agree to receive emails from Workplace Testing and agree to our Terms of Use and Privacy Policy. Lateral rotation is an anatomical term of motion describing rotation along the long axis of a joint. In lateral rotation, this movement is away from the midline of the body and occurs in the transverse plane.
As with most twisting motions, strain, awkward positioning, and repetition increase the chance for a work injury. Another term for lateral rotation is external rotation. Lateral rotation describes the movement of a body part or muscle group away from the center of the body and around the longitudinal axis of a bone.
Lateral rotation refers only to those movements taking place in the transverse plane.
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