Shoulder

Normal Anatomy of the Shoulder Joint

The shoulder is the most flexible joint in the body enabling a wide range of movements including:

forward flexion,
abduction,
adduction,
external rotation,
internal rotation, and
360-degree circumduction.

Shoulder instability is a chronic condition that causes frequent dislocations of the shoulder joint.

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.

Rotator cuff is the group of tendons in the shoulder joint providing support and enabling wider range of motion. Major injury to these tendons may result in tear of these tendons and the condition is called as rotator cuff tear. It is one of the most common causes of shoulder pain in middle aged adults and older individuals.

Frozen shoulder, also called adhesive capsulitis is a condition characterized by pain and loss of motion in 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, scapula. Shoulder impingement is also called as swimmer’s shoulder, tennis shoulder, or rotator cuff tendinitis.

Clavicle fracture, also called broken collarbone is a very common sports injury seen in people who are involved in 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. Broken clavicle may cause difficulty in lifting your arm because of pain, swelling and bruising over the bone.

Arthroscopy is a minimally invasive diagnostic and surgical procedure performed for joint problems. Shoulder arthroscopy is performed using a pencil-sized instrument called an Arthroscope. The arthroscope consists of a light system and camera to project images to a computer screen for your surgeon to view the surgical site. Arthroscopy is used to treat disease conditions and injuries involving the bones, cartilage, tendons, ligaments, and muscles of the shoulder joint.

The shoulder is a highly movable body joint that allows various movements of the arm. It is a ball and socket joint, where the head of the humerus (upper arm bone) articulates with the socket of the scapula (shoulder blade) called the glenoid. The two articulating surfaces of the bones are covered with cartilage, which prevents friction between the moving bones. The cartilage is lubricated by synovial fluid. Tendons and ligaments around the shoulder joint provide strength and stability to the joint.

The shoulder consists of 3 bones (humerus, scapula and clavicle), which together form a ball and socket joint and help in the flexible movement of the shoulder. The shoulder is supported and stabilized by strong muscles, ligaments and a rim of cartilage tissue called the labrum. Falls and other traumatic injuries to the shoulder can dislocate (displace) the ball of the humerus (upper arm bone) out of the socket of the shoulder joint backwards and cause a tear in the labrum. Posterior stabilization surgery aims to restore your shoulder stability and prevent future dislocations.

Total shoulder replacement is the replacement of the head of the humerus (upper arm bone) and the glenoid cavity (cavity of the shoulder blade) into which the humerus fits, with artificial prostheses to relieve pain, swelling and stiffness caused due to damage of cartilage at the articulating surfaces.

Playing more overhead sports activities and repeated use of shoulder at 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. Shoulder joint often dislocates in the forward direction (anterior instability) and it may also dislocate in backward or downward direction.

Acromioclavicular joint (AC joint) dislocation or shoulder separation is one of the most common injuries of the upper arm. It involves separation of the AC joint and injury to the ligaments that support the joint. The AC joint forms where the clavicle (collarbone) meets the shoulder blade (acromion).