An anterior shoulder dislocation occurs when the shoulder slides forward out of the socket. It is usually the result of a sports injury, fall, or traffic accident.

This shoulder injury is the most common type of dislocation. It can cause pain, deformity, and reduced function in the affected arm. A doctor will often need to put the arm back in its socket before checking for further damage. For this reason, a person with a dislocated shoulder should seek immediate medical attention.

People who dislocate their arm once often have a high risk of doing so again. Understanding the care journey is important for protecting the joint and reducing future injuries. However, full healing is possible through the use of a sling and physical therapy.

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A joint dislocation occurs when two bony surfaces in the body separate completely. This usually occurs due to a sudden injury or hard impact on the joint.

There are many different structures in the shoulder that allow it to move. Some important bony structures in the shoulder include:

  • the collarbone, or clavicle, which joins the shoulder to the rest of the body
  • the top of the upper arm or humerus, which has a ball shape
  • the glenoid, into which the ball of the upper arm fits

Shoulder joint dislocation affects the glenohumeral joint, where the ball at the top of the arm connects to the socket joint of the shoulder. Both bones in this joint give the shoulder improved flexibility. However, this shape also means that the glenohumeral joint is unstable, making dislocation common.

According to a 2023 article, around 50% of joint dislocations affect this joint. Of these, 95% to 97% are anterior socket dislocations.

Different types of shoulder dislocation vary depending on the direction in which the arm dislocates.

Anterior shoulder dislocation

“Anterior” means “front” or “forward.” This type of dislocation means the arm moves forward out of its socket. Anterior shoulder dislocation usually occurs when a person is holding the arm away from the body.

Posterior shoulder dislocation

“Posterior” means “behind” or “back.” Posterior shoulder dislocation occurs when the arm bone slides backward from the socket. It is less common than anterior shoulder dislocation and occurs when a person raises their arm in front of their body. Seizures are a common cause of posterior shoulder dislocation.

Read on to learn more about posterior shoulder dislocations.

Trauma is the cause of most anterior shoulder dislocations. For example, this can occur if a person falls onto an outstretched arm.

A heavy force from a fall or vehicle accident is also a common cause of anterior shoulder dislocation. After the first dislocation, damage to the tendons and ligaments in the shoulder — also known as the rotator cuff — can make future dislocations more likely.

Read on to learn more about the rotator cuff.

Risk factors

Over 2.5 times as many males experience anterior shoulder dislocation as females. It is most common from 15 to 30 years of age. People who play sports have a high rate of further anterior shoulder dislocations after returning to action. A 2016 study suggests that athletes returning to action after a dislocation have recurrence rates ranging from 37% to 90%.

Some people also have looser ligaments from birth. They may have a higher risk of shoulder dislocations.

An anterior shoulder dislocation has a distinct appearance. This includes the following features:

  • The injured shoulder hangs lower than the other one. The person may hold it away from their body.
  • The shoulder may twist outward.
  • An individual with a dislocated shoulder may use their other arm to support it.
  • The shoulder looks flat and square instead of round and curved.
  • The space between the shoulder and the chest is either full or empty, depending on where the bone has moved.
  • A person may be able to feel the bone underneath the space between the shoulder and the chest.
  • The socket where the bone should be is empty when touched.

Symptoms aside from deformity might include:

  • painful muscle spasms
  • swelling
  • numbness
  • weakness
  • bruising

Shoulder dislocations can be complete or partial. Complete dislocation means the tendon has separated entirely from the bone. It can tear ligaments and tendons and may cause nerve damage.

During a partial dislocation, or subluxation, the bone may move back into place without treatment. It may look uninjured and move normally. However, a partially dislocated shoulder can cause pain, and more dislocations can occur if the dislocation has caused tendon damage.

A doctor will often be able to diagnose a dislocation during a physical examination. They will ask how the dislocation occurred and whether it is an individual’s first one, as well as check for damage to the skin, blood supply, and nerves of the arm.

They may request imaging scans, including:

A doctor will often only request CT and MRI scans after resetting the shoulder and putting the arm back into the socket.

Treatment for anterior shoulder dislocation aims to put the arm back in place, relieve pain, and restore full use of the arm over time. There are both surgical and nonsurgical treatment approaches.


Doctors usually treat a mild to moderate anterior shoulder dislocation using nonsurgical methods. These include:

  • Closed reduction: A doctor or member of on-site medical personnel slowly and gently puts the arm back in its socket. They often administer pain relief medications or sedatives. However, pain often diminishes right away once the shoulder resets.
  • Slinging: After closed reduction, a doctor applies a sling to stop the arm from moving around and keep it still. A person should wear this until the next consultation with a doctor.
  • Cold therapy: A person can apply an ice pack to the shoulder around three or four times daily. This can help reduce pain and swelling.
  • Pain relief medications: People can take nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen to bring down swelling and relieve pain.
  • Physical therapy: Gentle muscle toning exercises can support recovery and restore the shoulder’s range of motion.

The shoulder may still feel like it slides out of its socket, even after rehabilitation. Some people wear a shoulder brace for extra support during physical activity. However, many people can lead a fully active life following rehabilitation from an anterior shoulder dislocation.


Surgery may be necessary if a doctor has not been able to reset the joint or after repeated dislocations. If a CT scan or MRI shows damage to the rotator cuff or surrounding bones, a person may need surgery to prevent future instability.

Some professional athletes with a high risk of repeated dislocations may choose surgery to treat their first shoulder dislocation.

Surgery may help in the following ways:

  • repairing the ligaments or making them tighter
  • repairing the labrum, or the cartilage around the socket
  • filling spaces in bone
  • rebuilding lost or damaged bone

It is best to receive physical therapy after surgery, as there is a high risk of shoulder stiffness afterward. Gently rebuilding and strengthening the shoulder and shoulder blade muscles can also help provide stability to the joint and prevent future dislocations.

Anterior shoulder dislocation is the most common dislocation. It occurs when trauma moves the ball joint at the top of the arm out of the shoulder’s socket. This type of dislocation can occur due to sports injuries, falls, or motor accidents and can lead to immediate deformity, pain, and swelling.

During treatment, a doctor aims to place the arm back into the joint before assessing the damage to the surrounding tendons, ligaments, and bone. For some people, surgery may be necessary. Physical therapy can help people achieve a good outcome and regain full use of the arm after treatment. However, some stiffness may continue.