The shoulder is a complex "engineering work" from all joints of the human body, consisting of five joints: Gleno-umeral (AG), Subdeltoideia, Acromioclavicular clavicular (AA), External-clavicular (EC) and scapular-thoracic (AND) (Kapandji 2000).
articulation Gleno-umeral It is a synovial joint multiaxial, ball and socket joint and performs movements in the three axes, wherein due to the potential mobility is inherently unstable (Weisenthal, 2000; Levangie e Norkin, 2001). It is engaged by the joint capsule, ligaments and muscles, helping to maintain stable joint and coaptada during movements (Weisenthal, 2000; Levangie e Norkin, 2001). It consists of a spherical surface, the humeral head, and a concave surface, the glenoid cavity. This cavity is irregular structure, shallow and has a joint surface smaller than the head of the humerus decreasing its stability and security (Kapandji, 2000; Levangie e Norkin, 2001). The glenoid cavity is deepened by the glenoid edging, increasing the surface of this, restoring the congruence of the articular surfaces (Kapandji, 2000; Levangie e Norkin, 2001).
The rotator cuff consists of four muscles, supraspinatus, infra-spinous, small round and subscapularis. The functions of the rotator cuff are the dynamic stabilization of the shoulder joint and the support rotation and abduction. The supraspinatus pulls the humeral head to the glenoid cavity, allowing the flattening of the glenohumeral joint. The infra-thorny and small round depress the humeral head and are external rotators. The subscapularis performs internal rotation and adduction, depressing the humerus (Seeley, Stephens e Tate, 2003). During the daily movements, the hood of the muscles of the rotator are susceptible to repeated micro trauma, which can result in structural damage. Oftentimes, the source of the injury is the collision of the humeral head and rotator cuff with bow coracoacromial, when the AG is flexed or abducted, which translates into pain in the joint region and shoulder periarticular, limiting mobility and an inefficient operation of arm (Santos and Bernardinelli, 2005).
The joint Subdeltoideia It is not a true joint anatomical point of view, but the physiological point of view. This joint is mechanically connected to the AG, whereby any movement of the latter produces movement in conjunction subdeltoideia (Villafrancas, 2001).
The acromion-clavicular joint Its main function is to maintain the relationship between the clavicle and scapula at the beginning of shoulder flexion and allow the scapula over the last rotating bending moments. This bending relates to the combination of motion scapular, clavicular e umeral (Kapandji, 2000).
The external-clavicular joint It is formed by joining the outer end of the clavicle and the sternum manubrium, It has a joint capsule surrounding the joint and which varies in thickness and strength. Assists the shoulder girdle in some movements (Kapandji, 2000).
The scapular-thoracic joint It is not a true joint in anatomical terms, It is a functional linkage. The scapular movements, They are associated with movements in EC and AA. The shoulder muscles facilitate the movements of the upper end properly positioned AG (Hall, 2000).
Understand how different anatomical structures that form the shoulder bind to each other, helps us to understand the workings of this joint, the mechanisms of injury and as challenging is the recovery of injured shoulder. Excluding traumatic causes, the main causes of shoulder pain are inflammation of the tendons (tendinitis) and inflammation of the bursae (bursites).
ache, uncomfortable or discomfort musculoskeletal the level of the shoulder, It is mainly due to situations and / or jobs with high demands on postural level or laying errors, application of excessive force to which the muscles are not prepared, of repetitions of movements / gestures or incorrect distribution of breaks in the activity held. Pain or shoulder discomfort is accepted as an indicator of possible risk situations to find the cause of musculoskeletal injuries related to work or / physical activities leisure and sports.
Injuries overuse and shoulder overload represent poor adjustment to repetitive stress and overload of activity. The most common injury is the shoulder impingement syndrome (compression syndrome) what, Generally, It is the result of the cumulative effect of many passages of the rotator cuff tendons under the arch coracoacromial, during the lifting movement of the arm, leading to compression or impact of these structures.
One of the cheapest and easiest ways to reduce the incidence of injuries will be the implementation of a prevention program. The practice of regular exercise, guided by a duly authorized professional, You can minimize the risk of musculoskeletal disorders. Physiotherapy has an important role since prevention to treatment of these pathologies.