The shoulder is a joint consisting of bone, muscle, tendons and ligaments. Tendons are tissues that connect the muscles to the bones and help the muscles to move the shoulder. Ligaments connect bones and have a role to hold the bones together and thereby stabilize the joint.
Shoulder Pain, Shoulder Injuries, Shoulder Treatment
The shoulder is made up of three bones – the scapula, humerus and clavicle which make 4 joints: glenohumeral, acromioclavicular, sternoclavicular and scapulothoracic. The shoulder joint (glenohumeral) is surrounded by a joint capsule filled with liquid which lubricates the joint and makes it function. Ligaments are integrated in the joint capsule and both of them represent static shoulder stabilizers, meaning that they stabilize our shoulders automatically and involuntarily.
Besides them, there are also the dynamic shoulder stabilizers, which are made up of four muscles – supraspinatus, infraspinatus, teres minors, and subscapularis. The tendons of these muscles attach to the humerus and they are responsible for the humerus standing firmly in the glenoid. This part is very shallow and flat, and its edge is surrounded by soft tissue called labrum that deepens it and that the ligaments attach themselves to as well.
The shoulder is the most movable joint of the body and therefore shoulder pain and shoulder injuries are relatively frequent occurrences. Its function depends on the simultaneous interaction between the static stabilizers as well as the dynamic ones. Because of its complexity, the shoulder is often called the shoulder complex. The loss of only one stability factor leads to a condition named shoulder instability.