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. Inflammation is the body's natural response to injury. The warning signs that inflammation presents are redness, swelling, heat, and pain.
The shoulder consists of a ball-and-socket joint formed by the upper end of the humerus (upper arm bone) and a cavity in the shoulder blade called the glenoid. The glenoid cavity is surrounded by a rim of cartilage called the labrum. The labrum adds depth to the cavity making the joint more stable and positions the ball within the socket.
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, can place a lot of stress on the shoulder. While pitching, the arm is thrown outward and backward to generate speed.
The term SLAP (superior –labrum anterior-posterior) lesion or SLAP tear refers to an injury of the superior labrum of the shoulder.
Throwing injuries of the shoulder are injuries sustained as a result of trauma by athletes during sports activities that involve repetitive overhand motions of the arm as in baseball, American football, volleyball, rugby, tennis, track and field events, etc. Throwing injuries are mostly seen in the shoulder and elbow and can occur due to improper techniques, training errors, muscle imbalance, and overuse of muscles.
The acromioclavicular joint is part of the shoulder joint. It is formed by the union of the acromion, a bony process of the shoulder blade, and the outer end of the collar bone or clavicle. The joint is lined by cartilage that gradually wears with age as well as with repeated overhead or shoulder level activities such as basketball. The condition is referred to as AC arthritis or acromioclavicular arthritis.
The break or fracture of the clavicle (collarbone) is a common sports injury associated with contact sports such as football and martial arts, as well as impact sports such as motor racing. A direct blow over the shoulder that may occur during a fall on an outstretched arm or a motor vehicle accident may cause the clavicle bone to break.
The humerus is the bone that forms the upper arm. It articulates with the glenoid cavity of the scapula (shoulder blade) to form the shoulder joint and with the lower arm bones – the ulna and radius – to form the elbow joint. The proximal humerus is the upper end of the arm bone that forms the shoulder joint. The humerus is broadly divided into the head, neck and shaft region.
Your biceps muscle has two heads, a long head, and a short head, which are both attached to the shoulder. The long head of the biceps tendon is a tough band of connective fibrous tissue that attaches the long head of the biceps to the top of the shoulder socket.
Instability may be described by the direction in which the humerus is subluxated or dislocated from the glenoid. When it occurs in several directions it is referred to as multidirectional instability.
A tear in the rotator cuff can cause pain and disability. It can occur from degeneration of the rotator cuff due to overuse or from a sudden injury. Massive rotator cuff tears involve tears in two complete tendons of the rotator cuff. A tear of more than 5 cm is described as massive. A massive tear may be associated with degeneration and retraction of the tendon and can be difficult to repair if treatment is delayed.