Common shoulder injuries: Causes, symptoms, and treatment options

The shoulder joint is a complicated mechanism that supports a variety of motions, such as extension, flexion, and rotation. It is comprised of a number of bones, muscles, and related tissues that cooperate to give it support and mobility.  In this article, we will explore the shoulder anatomy in more detail, including its bones, muscles, and associated structures.

Bones of the Shoulder Joint

The shoulder joint is formed by articulating three bones: the humerus, scapula, and clavicle. Each bone plays a vital role in the function of the shoulder joint.

Humerus

Since it is the longest bone in the upper arm, the humerus joins the shoulder to the elbow. The glenoid fossa, a small socket on the scapula, receives the head of the humerus. The glenoid fossa is reinforced by a rim of fibrocartilage called the glenoid labrum, which helps to deepen the socket and improve stability.

Scapula

The flat, triangular scapula, sometimes referred to as the shoulder blade, is located near the back of the ribcage. The scapula has several important bony landmarks, including the acromion process, which forms the bony prominence at the shoulder’s peak, and the coracoid process, which provides attachment for several muscles and ligaments.

Clavicle

The clavicle, or collarbone, is a long, S-shaped bone that connects the arm to the sternum (breastbone). The clavicle helps to provide stability to the shoulder joint and protect it from injury.

Muscles of the Shoulder Joint

Now we shall see the muscles in shoulder anatomy. The shoulder joint is surrounded by a muscle group known as the rotator cuff. These muscles originate from the scapula and attach to the humerus, forming a cuff around the joint. The rotator cuff muscles function to stabilize the shoulder joint during movement and help to rotate the arm.

Supraspinatus

The supraspinatus muscle is on the back of the scapula and runs from the scapula to the top of the humerus. This muscle is responsible for initiating abduction (lifting the arm away from the body) and stabilizing the humeral head in the glenoid fossa.

Infraspinatus

The infraspinatus muscle is on the back of the scapula below the supraspinatus. It runs from the scapula to the back of the humerus. It is responsible for external rotation (rotating the arm away from the body) and stabilizing the humeral head in the glenoid fossa.

Teres Minor

The teres minor muscle is located on the back of the scapula and runs from the scapula to the back of the humerus. This muscle is responsible for external rotation and helps to stabilize the shoulder joint.

Subscapularis

The subscapularis muscle is located on the front of the scapula and runs from the scapula to the front of the humerus. It is responsible for internal rotation (rotating the arm towards the body) and helps to stabilize the humeral head in the glenoid fossa.

Associated Structures of the Shoulder Joint

In addition to the bones and muscles, the shoulder joint contains several other structures studied in shoulder anatomy that help provide stability and mobility.

Glenoid Labrum

The glenoid labrum is a rim of fibrocartilage that surrounds the glenoid fossa. It helps to deepen the socket and improve stability.

Joint Capsule

The joint capsule is a fibrous sac that surrounds the shoulder joint. It helps to hold the bones in place and provides a barrier to prevent the spread of infection.

Ligaments

The shoulder joint is supported by several ligaments, which are strong bands of fibrous tissue that connect bones to other bones. The ligaments of the shoulder joint include the coracohumeral ligament, which connects the humerus to the coracoid process of the scapula, and the superior, middle, and inferior glenohumeral ligaments, which connect the humerus to the glenoid fossa.

Bursae

Bursae are small, fluid-filled sacs that provide cushioning and lessen friction between bones and soft tissues. The shoulder joint contains several bursae, including the subacromial bursa, which sits between the acromion and the rotator cuff tendons.

Common shoulder injuries

One of the most movable joints is the shoulder joint in the human body, and it is prone to various injuries, like the hip joint. Shoulder injuries can occur due to trauma, overuse, or degenerative changes. This article will explain some of the most common shoulder injuries, their causes, symptoms, and treatment options.

Rotator Cuff Tears

A rotator cuff is a muscle group including the tendons surrounding the shoulder joint, and it helps stabilizes and move the shoulder. Rotator cuff tears is a common form of shoulder injury, particularly in athletes who partake in overhead sports like baseball, tennis, and swimming.

• Causes: Rotator cuff tears can occur due to trauma, like a fall or blow to the shoulder, or overuse, such as repetitive overhead activities. Degenerative changes due to ageing can also weaken the rotator cuff tendons and prones them to tearing.
• Symptoms: Symptoms of a rotator cuff tear include pain, weakness, and loss of range of motion in the shoulder. The pain may be sharp, sudden, dull, achy, and may worsen at night. There may also be a clicking or popping sensation in the shoulder.
• Treatment: Treatment options for rotator cuff tears depend on the severity of the injury. Mild to moderate tears may be treated with rest, ice, and physical therapy to strengthen the rotator cuff muscles. Severe tears may require surgery to repair the torn tendons.

Frozen Shoulder

Frozen shoulder, also called adhesive capsulitis, is when the shoulder joint becomes immovable and painful, making it difficult to move.

• Causes: The exact cause of a frozen shoulder is unknown, but it is thought to occur due to a combination of factors, including trauma, immobilization, and underlying medical conditions such as diabetes or thyroid disorders.
• Symptoms: Symptoms of a frozen shoulder include pain, stiffness, and a small range of motion in the shoulder. The pain may be dull and achy and may worsen at night. The stiffness may make it difficult to perform activities of daily life, such as dressing, grooming, and reaching overhead.
• Treatment: Treatment for a frozen shoulder typically involves physical therapy to improve the range of motion and reduce pain. In some cases, corticosteroid injections may reduce inflammation and relieve pain. Surgery may be necessary in severe cases.

Shoulder Impingement Syndrome

Shoulder impingement syndrome occurs when the rotator cuff tendons become compressed or pinched between the shoulder bones, causing inflammation and pain.

• Causes: Shoulder impingement syndrome can occur due to overuse or repetitive overhead activities, such as throwing a baseball or painting a ceiling. Poor posture, weak rotator cuff muscles, and bone spurs can also contribute to impingement syndrome.
• Symptoms: Symptoms of shoulder impingement syndrome include pain, weakness, and limited range of motion in the shoulder. The pain may be sharp, sudden, dull, and achy and may worsen with overhead activities.
• Treatment: Treatment options for shoulder impingement syndrome depend on the severity of the injury. Mild cases may be treated with rest, ice, and physical therapy to strengthen the rotator cuff muscles and improve posture. Severe cases may require surgery to remove bone spurs or repair damaged tissues.

Shoulder Dislocation

Shoulder dislocation occurs when the head of the humerus bone pops out of the glenoid fossa, causing pain and instability in the shoulder.

• Causes: Shoulder dislocation can occur due to trauma, such as a fall or blow to the shoulder, or overuse, such as repetitive overhead activities.
• Symptoms: Symptoms of shoulder dislocation include pain, swelling, and instability in the shoulder. The arm may appear out of place and may be difficult to move.
• Treatment: Treatment for shoulder dislocation typically involves repositioning the humerus bone back into the glenoid fossa, known as a closed reduction. Following the closed reduction, the shoulder must be immobilized in a sling or brace for several weeks to allow the tissues to heal. Physical therapy may also be recommended to strengthen the muscles and improve the range of motion.

Shoulder Arthritis

Shoulder arthritis is when the cartilage that lines the shoulder joints wears away, causing pain and stiffness.

• Causes: Shoulder arthritis can occur due to degenerative changes associated with ageing or a previous shoulder injury.
• Symptoms: Symptoms of shoulder arthritis include pain, stiffness, and limited range of motion in the shoulder. The pain may be dull and achy and may worsen with activity.
• Treatment: Treatment options for shoulder arthritis depend on the severity of the condition. Mild cases may be treated with rest, ice, and physical therapy to improve the range of motion and relieve pain. More severe cases may require surgery to replace the damaged joint with an artificial joint.

• Conclusion

Shoulder injuries can be painful and debilitating, but many treatment options are available to help relieve symptoms and improve function. If you are experiencing shoulder pain or other symptoms, seeking medical attention as soon as possible is important to prevent further damage and receive the appropriate treatment. With the right care, most shoulder injuries can be successfully treated, allowing you to return to normal activities as soon as possible.

Frequently asked questions

What is the most common cause of rotator cuff tears?

Rotator cuff tears can occur due to various factors, including trauma, overuse, and degenerative changes. However, the most common cause is overuse, particularly among athletes who engage in overhead sports such as baseball, tennis, and swimming.

Can a frozen shoulder be prevented?

While the exact cause of frozen shoulder is unknown, some steps can be taken to reduce the risk of developing this condition. Maintaining good posture, avoiding prolonged immobilization, and performing regular exercises to maintain shoulder mobility can help prevent frozen shoulder.

What is the best treatment for shoulder impingement syndrome?

The treatment for shoulder impingement syndrome depends on the severity of the injury. Mild cases may be treated with rest, ice, and physical therapy to strengthen the rotator cuff muscles and improve posture. Severe cases may require surgery to remove bone spurs or repair damaged tissues.

Can shoulder arthritis be treated without surgery?

Mild cases of shoulder arthritis may be treated with rest, ice, and physical therapy to improve the range of motion and relieve pain. However, more severe cases may require surgery to replace the damaged joint with an artificial joint.

How long does it take to recover from a shoulder dislocation?

The recovery time for shoulder dislocation depends on the severity of the injury and the individual’s overall health. In most cases, the shoulder must be immobilized in a sling or brace for several weeks to allow the tissues to heal. Physical therapy may also be recommended to strengthen the muscles and improve the range of motion. It may take several months to recover from a shoulder dislocation fully.