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Shoulder

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Shoulder Anatomy

The shoulder is the most flexible joint in the body that enables a wide range of movements including forward flexion, abduction, adduction, external rotation, internal rotation, and 360-degree circumduction. Thus, the shoulder joint is considered the most insecure joint of the body, but the support of ligaments, muscles, and tendons function to provide the required stability. 

Bones of the Shoulder

The shoulder joint is a ball and socket joint made up of three bones, namely the humerus, scapula, and clavicle. 

Humerus

The end of the humerus or upper arm bone forms the ball of the shoulder joint. An irregular shallow cavity in the scapula called the glenoid cavity forms the socket for the head of the humerus to fit in. The two bones together form the glenohumeral joint, which is the main joint of the shoulder.

Scapula and Clavicle

The scapula is a flat triangular-shaped bone that forms the shoulder blade. It serves as the site of attachment for most of the muscles that provide movement and stability to the joint. The scapula has four bony processes - acromion, spine, coracoid and glenoid cavity. The acromion and coracoid process serve as places for attachment of the ligaments and tendons. 

The clavicle bone or collarbone is an S-shaped bone that connects the scapula to the sternum or breastbone. It forms two joints: the acromioclavicular joint, where it articulates with the acromion process of the scapula and the sternoclavicular joint where it articulates with the sternum or breast bone. The clavicle also forms a protective covering for important nerves and blood vessels that pass under it from the spine to the arms.

Soft Tissues of the Shoulder 

The ends of all articulating bones are covered by smooth tissue called articular cartilage, which allows the bones to slide over each other without friction, enabling smooth movement. Articular cartilage reduces pressure and acts as a shock absorber during movement of the shoulder bones. Extra stability to the glenohumeral joint is provided by the glenoid labrum, a ring of fibrous cartilage that surrounds the glenoid cavity. The glenoid labrum increases the depth and surface area of the glenoid cavity to provide a more secure fit for the half-spherical head of the humerus.

Ligaments of the Shoulder

Ligaments are thick strands of fibers that connect one bone to another. The ligaments of the shoulder joint include:

Coracoclavicular ligaments: These ligaments connect the collarbone to the shoulder blade at the coracoid process.
Acromioclavicular ligament: This connects the collarbone to the shoulder blade at the acromion process. 
Coracoacromial ligament: It connects the acromion process to the coracoid process. 
Glenohumeral ligaments: A group of 3 ligaments that form a capsule around the shoulder joint and connect the head of the arm bone to the glenoid cavity of the shoulder blade. The capsule forms a watertight sac around the joint. Glenohumeral ligaments play a very important role in providing stability to the otherwise unstable shoulder joint by preventing dislocation.

Muscles of the Shoulder

The rotator cuff is the main group of muscles in the shoulder joint and is comprised of 4 muscles. The rotator cuff forms a sleeve around the humeral head and glenoid cavity, providing additional stability to the shoulder joint while enabling a wide range of mobility. The deltoid muscle forms the outer layer of the rotator cuff and is the largest and strongest muscle of the shoulder joint.

Tendons of the Shoulder

Tendons are strong tissues that join muscle to bone allowing the muscle to control the movement of the bone or joint. Two important groups of tendons in the shoulder joint are the biceps tendons and rotator cuff tendons.

Bicep tendons are the two tendons that join the bicep muscle of the upper arm to the shoulder. They are referred to as the long head and short head of the bicep.

Rotator cuff tendons are a group of four tendons that join the head of the humerus to the deeper muscles of the rotator cuff. These tendons provide more stability and mobility to the shoulder joint.

Nerves of the Shoulder

Nerves carry messages from the brain to muscles to direct movement (motor nerves) and send information about different sensations such as touch, temperature, and pain from the muscles back to the brain (sensory nerves). The nerves of the arm pass through the shoulder joint from the neck. These nerves form a bundle at the region of the shoulder called the brachial plexus. The main nerves of the brachial plexus are the musculocutaneous, axillary, radial, ulnar and median nerves.

Blood vessels of the Shoulder

Blood vessels travel along with the nerves to supply blood to the arms. Oxygenated blood is supplied to the shoulder region by the subclavian artery that runs below the collarbone. As it enters the region of the armpit, it is called the axillary artery and further down the arm, it is called the brachial artery.

The main veins carrying de-oxygenated blood back to the heart for purification include:

Axillary vein: This vein drains into the subclavian vein.
Cephalic vein: This vein is found in the upper arm and branches at the elbow into the forearm region. It drains into the axillary vein.
Basilic vein: This vein runs opposite the cephalic vein, near the triceps muscle. It drains into the axillary vein.

Rotator Cuff Tear

Rotator Cuff Tear

A rotator cuff is a group of tendons in the shoulder joint that provides support and enables a wide range of motion. A major injury to these tendons may result in rotator cuff tears. It is one of the most common causes of shoulder pain in middle-aged and older individuals.

Shoulder Pain

Shoulder Pain

Pain in the shoulder may suggest an injury, which is more common in athletes participating in sports such as swimming, tennis, pitching, and weightlifting. The injuries are caused due to the over usage or repetitive motion of the arms.

Subluxation

Subluxation

Subluxation usually occurs from falls or a direct blow to your shoulder. It can also be caused due to a previous shoulder injury or if the ligaments in your shoulder are loose. Subluxations tend to recur due to laxity in the ligaments.

Shoulder Impingement

Shoulder Impingement

Shoulder impingement is the inflammation of the tendons of the shoulder joint. It is one of the most common causes of pain in the shoulder. Shoulder impingement is also called swimmer’s shoulder, tennis shoulder or rotator cuff tendinitis.

SLAP Tears

SLAP Tears

The term SLAP (superior –labrum anterior-posterior) lesion or SLAP tear refers to an injury of the superior labrum of the shoulder. The most common causes include falling on an outstretched arm, repetitive overhead actions such as throwing and lifting a heavy object.

Arthritis of the Shoulder

Arthritis of the Shoulder

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.

Frozen Shoulder

Frozen Shoulder

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 Instability

Shoulder Instability

Shoulder instability is a chronic condition that causes frequent dislocation of the shoulder joint. A dislocation occurs when the end of the humerus (ball portion) partially or completely dislocates from the glenoid (socket portion) of the shoulder.

Shoulder Labral Tear

Shoulder Labral Tear

Traumatic injury to the shoulder or overuse of the shoulder (throwing, weightlifting) may cause the labrum to tear. In addition, aging may weaken the labrum leading to injury.

Shoulder Dislocation

Shoulder Dislocation

Sports that involve overhead movements and repeated use of the shoulder at your workplace may lead to sliding of the upper arm bone from the glenoid. The dislocation might be a partial dislocation (subluxation) or a complete dislocation causing pain and shoulder joint instability.

Little League Shoulder

Little League Shoulder

Little league shoulder is an injury to the growth plate of the upper arm bone at the shoulder joint of children. It is an overuse injury caused by repeated pitching or throwing, especially in children between the ages of 10 to 15 years.

Shoulder Trauma

Shoulder Trauma

Shoulder injuries most commonly occur in athletes participating in sports such as swimming, tennis, pitching, and weightlifting. The injuries are caused due to the over usage or repetitive motion of the arms.

Clavicle Fracture

Clavicle Fracture

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.

Glenoid Fractures

Glenoid Fractures

Fractures of the glenoid are rare but can occur due to major trauma or during high-energy sports activities. The symptoms of a glenoid fracture may include shoulder pain, swelling, a deformity at the site of the fracture and inability to move the arm.

Baseball and Shoulder Injuries

Baseball and Shoulder Injuries

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.

Sternoclavicular Joint (SC joint)

Sternoclavicular Joint (SC joint)

The sternoclavicular joint is the joint between the breastbone (sternum) and the collar bone (clavicle). The SC joint is one of the 4 joints that complete the shoulder and is the only joint that links the arm to the body.

Internal Impingement of the Shoulder

Internal Impingement of the Shoulder

Internal shoulder impingement can be described as a pathological condition resulting from repetitive impingement of the internal surface of the rotator cuff by the bones at the back of the glenohumeral joint.

Treatment of Throwing Injuries of the Shoulder

Treatment of Throwing Injuries 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.

Shoulder Labral Tear with Instability

Shoulder Labral Tear with Instability

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.

Proximal Biceps Tendon Rupture

Proximal Biceps Tendon Rupture

The biceps muscle is the muscle of the upper arm which is necessary for the movement of the shoulder and elbow. It is made of a ‘short head’ and a ‘long head’ which function together. These are connected to the shoulder joint by two tendons called the proximal biceps tendons and to the elbow joint by a single distal biceps tendon.

Long Head Biceps Tendon Rupture

Long Head Biceps Tendon Rupture

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.

Multidirectional Instability of the Shoulder

Multidirectional Instability of the Shoulder

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.

Massive Retracted Rotator Cuff Tear

Massive Retracted Rotator Cuff Tear

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.

Hill-Sachs Lesion

Hill-Sachs Lesion

Your shoulder consists of a ‘ball-and-socket joint’. The humerus (upper arm bone) has a rounded head (ball) that is attached to the glenoid cavity (socket) in the shoulder blade. Certain injuries can cause dislocation of the joint and damage to the humeral head. Damage to the back and outer portion of the humeral head can result in a defect called a Hill-Sachs lesion.

Rotator Cuff Pain

Rotator Cuff Pain

The rotator cuff consists of a group of tendons and muscles that surround and stabilize the shoulder joint. These tendons allow a wide range of movement of the shoulder joint across multiple planes. Irritation or injury to these tendons can result in rotator cuff pain.

Proximal Biceps Tenodesis

Proximal Biceps Tenodesis

Proximal biceps tenodesis is the surgical reattachment of a torn proximal biceps tendon, which connects the upper part of your biceps muscle to the shoulder.

Bicep Tendon Rupture at Shoulder

Bicep Tendon Rupture

The biceps muscle is present on the front of your upper arm and functions to help you bend and rotate your arm. The biceps tendon is a tough band of connective fibrous tissue that attaches your biceps muscle to the bones in your shoulder on one side and the elbow on the other side.

SLAP Repair

SLAP Repair

A SLAP repair is indicated to treat the torn labrum of the shoulder socket when conservative treatment measures such as NSAIDs (non-steroidal anti-inflammatory medications) and physical therapy do not relieve the symptoms of a SLAP tear.

Arthroscopic Bankart Repair

Arthroscopic Bankart Repair

The labrum can sometimes tear during a shoulder injury. A specific type of labral tear that occurs when the shoulder dislocates is called a Bankart tear. This is a tear to a part of the labrum called the inferior glenohumeral ligament and is common in the young who sustain a dislocation of the shoulder. A Bankart tear makes the shoulder prone to repeat dislocation in patients under 30 years of age.

Shoulder Labrum Reconstruction

Shoulder Labrum Reconstruction

Traumatic injury to the shoulder or overuse of the shoulder by excessive throwing or weightlifting can cause a labral tear. In addition, the aging process may weaken the labrum, leading to injury secondary to wear and tear.

Shoulder Stabilization

Shoulder Stabilization

Shoulder stabilization surgery is performed to improve stability and function to the shoulder joint and prevent recurrent dislocations. It can be performed arthroscopically, depending on your particular condition, with much smaller incisions. Arthroscopic stabilization is a surgical procedure to treat chronic instability of the shoulder joint.

Shoulder Arthroscopy

Shoulder Arthroscopy

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 that projects images of the surgical site onto a computer screen for your surgeon to clearly view.

Distal Clavicle Excision

Distal Clavicle Excision

Distal clavicle excision is a procedure which involves removal of the outer end of the clavicle (collarbone) to treat shoulder pain and disability due to arthritis or impingement.

Capsular Release

Capsular Release

A capsular release of the shoulder is surgery performed to release a tight and stiff shoulder capsule, a condition called frozen shoulder or adhesive capsulitis. The procedure is usually performed arthroscopically through keyhole-size incisions.

Pectoralis Major Tears/Repairs

Pectoralis Major Tears/Repairs

The pectoralis muscle is a large fan-shaped muscle comprised of the pectoralis major and pectoralis minor muscles that stretch from the armpit to the collarbone and down across the lower chest region on both sides of the chest.

ORIF of the Clavicle Fractures

ORIF of the Clavicle Fractures

A clavicle fracture refers to a broken collarbone and is a common 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, a fall on an outstretched arm, or a motor vehicle accident may also cause the clavicle bone to break.

Subacromial Decompression

Subacromial Decompression

Subacromial decompression is a surgical procedure performed for the treatment of a condition called shoulder impingement. In shoulder impingement, the degree of space between the rotator cuff tendon and shoulder blade is decreased due to irritation and swelling of the bursa or due to development of bone spurs.

Am I a Candidate for Shoulder Surgery?

Am I a Candidate for Shoulder Surgery?

More people are considering shoulder surgery to manage shoulder problems thanks to advances in technology and equipment. Surgery is now minimally invasive and can be performed on an outpatient basis with faster recovery and fewer complications. But what are your other options and when is the right time to turn to surgery?