The term arthritis literally means inflammation of a joint but is generally used to describe any condition in which there is damage to the cartilage. Damage of the cartilage in the shoulder joint causes shoulder arthritis.
A break in a bone that makes up the shoulder joint is called a shoulder fracture.
Types of Fractures
The clavicle and end of the humerus closest to the shoulder are the bones that usually get fractured. The scapula on the other hand is not easily fractured because of its protective cover by the surrounding muscles and chest tissue.
The rotator cuff is a group of tendons in the shoulder joint providing support and enabling a wide range of motion. Major injury to these tendons may result in tear of these tendons, a condition called rotator cuff tear.
Playing more overhead sports and repeated use of the shoulder at the workplace may lead to sliding of the upper arm bone, the ball portion, from the glenoid–the socket portion of the shoulder. The dislocation might be a partial dislocation (subluxation) or a complete dislocation causing pain and shoulder joint instability.
The term SLAP (superior –labrum anterior-posterior) lesion or SLAP tear refers to an injury of the superior labrum of the shoulder. The labrum is a ring of fibrous cartilage surrounding the glenoid for stabilization of the shoulder joint.
Frozen shoulder, also called adhesive capsulitis, is a condition characterized by pain and loss of motion in the shoulder joint. It is more common in older adults aged between 40 and 60 years and is more common in women than men.
Shoulder impingement is the condition of inflammation of the tendons of the shoulder joint. It is one of the most common causes of pain in the adult shoulder. The shoulder is a 'ball-and-socket' joint. A ‘ball' at the top of the upper arm bone, humerus, fits neatly into a 'socket’, called the glenoid, which is part of the shoulder blade or scapula. Shoulder impingement is also called as swimmer’s shoulder, tennis shoulder, or rotator cuff tendinitis.
Shoulder instability is a chronic condition that causes frequent dislocations of the shoulder joint.
Causes of Shoulder Instability
A dislocation occurs when the end of the humerus (the ball portion) partially or completely dislocates from the glenoid (the socket portion) of the shoulder. A partial dislocation is referred to as a subluxation whereas a complete separation is referred to as a dislocation.
Traumatic injury to the shoulder or overuse of shoulder (throwing, weightlifting) may cause labral tear. In addition, ageing may weaken the labrum leading to injury.
Shoulder injuries in baseball players are usually associated with pitching. While this overhand throwing activity can produce great speed and distance for the ball, when performed repeatedly, it can place a lot of stress on the shoulder. While pitching, the arm is thrown outward and backward to generate speed. This action forces the head of the humerus forward, stressing the surrounding ligaments and tendons. These stresses can lead to injuries, causing pain and inflammation.