Dislocated Shoulder

The shoulder, a ball-and-socket joint, comprises three bones: the humerus, scapula, and clavicle, enabling a wide range of arm motion. Its stability, however, primarily relies on supporting muscles, tendons, and ligaments, not just the bones. Despite its design for mobility, the shoulder is highly susceptible to injuries like dislocation.

What Is Shoulder Dislocation?

A dislocated shoulder is an injury in which the upper arm bone (humerus) has moved out of the cup-shaped socket of the shoulder blade (glenoid). As the most flexible joint in the human body, the shoulder allows for a wide range of motions. However, this flexibility also makes it more prone to dislocation.

What Are the Types of Dislocated Shoulders?

Dislocations can be classified depending on how far the humerus has been moved:

• Complete Dislocation (Luxation)

  - This occurs when the head of the humerus is completely separated and pushed out of the glenoid. It may result in visible deformity, significant pain and loss of function.

• Partial Dislocation (Subluxation)

  - In this type, the humeral head is only partially displaced from the glenoid but does not come out. The deformity is not visibly obvious but can still cause pain and instability.

What Are the Symptoms of a Dislocated Shoulder?

Symptoms of a dislocated shoulder may vary depending on the severity of the dislocation, but common signs include:

• Visible deformity
• Swelling and bruising
• Inability to move the arm
• Weakness
• Severe shoulder pain

What Causes Shoulder Dislocations?

Shoulder dislocations are typically caused by a strong force that pushes, pulls, or twists the humerus out of the glenoid. Common causes include:

• Sports Injuries - High-impact and contact sports like football and hockey frequently result in shoulder dislocations due to the intense forces involved.
• Traumatic Injury - A direct, hard blow to the shoulder from a fall or other accident can force the joint out of alignment.
• Repetitive Strain - Activities that involve repeated, strenuous shoulder movements can stress the joint over time, increasing the likelihood of dislocation.
• Previous Dislocation - Once your shoulder has dislocated, the ligaments and other soft tissues that keep the joint stable often get stretched or torn. This damage makes the shoulder more vulnerable to dislocating again.

What Are the Risk Factors for a Dislocated Shoulder?

Anyone can experience a shoulder dislocation, but some people have a higher risk than others, including:

• Athletes who play contact sports
• People who do activities like swimming, pitching, or weightlifting
• Individuals who have had shoulder dislocations in the past

What Are the Complications of a Dislocated Shoulder?

When the shoulder dislocates, the bones shifting out of place can damage the surrounding tissues that support the joint. Common complications include:

• Bone Fractures - A dislocated shoulder can occur together with fractures of the bones around the shoulder.
• Nerve Damage - Nerves around the shoulder joint can be stretched, compressed, or even torn, leading to numbness, weakness or poor circulation.
• Tearing of Soft Tissues - The muscles, ligaments and tendons that support the shoulder joint can be stretched or torn during dislocation.
• Recurrent Dislocations - Once your shoulder has been dislocated, it is more prone to future dislocations.

How Are Dislocated Shoulders Diagnosed?

Dislocated shoulders are diagnosed through a combination of clinical examination and imaging tests.

Clinical Examination

The shoulder specialist begins by asking how the injury occurred, the position of your arm immediately after, and the symptoms you experienced. Then, they will physically examine the affected shoulder to look for obvious signs of deformity to identify the position of the humeral head and to assess your range of motion.

Imaging Tests

After a clinical exam, imaging tests are typically used to assess internal damage from a dislocation. An X-ray is usually the first step. For more detailed evaluation of soft tissue damage or complex fractures, an MRI or CT scan may be ordered.

How Are Dislocated Shoulders Treated?

A shoulder dislocation is an emergency that requires immediate medical attention. Head to the emergency room right away. Doctors will perform a closed reduction (or manipulation), a non-surgical procedure to gently guide your arm back into its socket. You may be given a mild sedative or muscle relaxer beforehand to help your body relax, as severe pain typically subsides once the shoulder is back in place.

Once the shoulder has been reset, you may need other treatments, including:

• Immobilisation - The injured arm is placed in a splint or sling for several days to weeks. This prevents the shoulder from moving as it heals, allowing the joint and surrounding tissues to heal properly.
• Pain Management - To aid in healing and shoulder strengthening, medication may be prescribed for pain management. Doctors commonly recommend non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen, or naproxen.
• Ice Therapy - Applying an ice pack to the injured shoulder helps with the pain and swelling. The sore area can be iced 3 to 4 times a day.
• Rehabilitation - Physiotherapy helps restore strength and movement. Rehab generally includes gentle motion exercises, stretches and other exercises to strengthen shoulder muscles.

Surgical intervention may be necessary when a shoulder dislocation recurs repeatedly or the joint remains unstable despite non-surgical treatments. Surgery may also be recommended when there are significant injuries to the shoulder's muscles or bones.

How Can You Prevent Dislocating Your Shoulders?

While not always preventable, you can take steps to reduce your risk of shoulder dislocation. Here are some tips to prevent dislocating your shoulder:

1. Stretch and warm up before playing sports or working out.
2. Wear protective gear when playing contact sports.
3. Practice proper techniques to reduce strain on the shoulder.
4. Be cautious with your environment to avoid falls and other shoulder injuries.
5. Give your body time to rest and recover after intense activity.
6. Exercise regularly to strengthen shoulder muscles.
7. Avoid repetitive overhead motions if possible.

About Our Orthopaedic Surgeon

Dr James Tan Chung Hui

Senior Consultant
Orthopaedic Surgery, Sports & Exercise Medicine
MBBS (S’pore), MRCS (Edin), MMed (Orth), FRCS Orth & Tr (Edin)

Dr James Tan graduated from the NUS Faculty of Medicine and obtained a Master of Medicine (Orthopaedics). He is widely recognised as an orthopaedic surgeon in Singapore for his treatment techniques for shoulder pain and other shoulder conditions. With over 10 years of experience, he specialises in minimally invasive (keyhole) tendon and ligament repair, joint replacement, and muscle-tendon transfers of the shoulder joint.