Dislocated Shoulder: Symptoms, Types, Causes and Treatment

A dislocated shoulder is not just a painful injury—it can affect your ability to work, play, and even carry out daily activities. Understanding the signs, types, causes, and modern treatments for this common joint dislocation can help you seek the right care and avoid long-term problems. This in-depth guide explores what happens when the shoulder joint is forced out of place, the different forms this injury can take, why it occurs, and how it is best managed.

Symptoms of Dislocated Shoulder

Recognizing the symptoms of a dislocated shoulder quickly can make a big difference in outcomes. The shoulder is the most frequently dislocated major joint in the body, and its symptoms are usually hard to ignore. However, the full spectrum of signs—especially less obvious ones—are important to understand for early detection and prompt treatment.

Symptom	Description	Commonality	Source(s)
Severe Pain	Intense, sudden pain in the shoulder area	Very common	2 12
Visible Deformity	Out-of-place or “square” shoulder shape	Common	2 12
Limited Motion	Inability to move the arm or shoulder	Very common	2 12
Swelling/Bruising	Localized swelling and bruising around joint	Common	12

Table 1: Key Symptoms

Pain and Immediate Signs

The most immediate and universal symptom of a shoulder dislocation is severe pain, often described as sharp and incapacitating. The pain typically starts the moment the joint is forced out of place. Any attempt to move the arm usually worsens it, and people often instinctively cradle the injured limb to avoid movement 2 12.

Deformity and Loss of Function

A classic sign is the visible deformity of the shoulder. The normal rounded contour may appear flattened or squared off. The patient typically cannot move the shoulder, especially in certain directions, and may report a sensation of the shoulder “popping out” 2 12.

Swelling, Bruising, and Nerve Symptoms

Swelling and bruising around the shoulder joint develop soon after the injury. In some cases, numbness, tingling, or weakness in the arm or hand can occur if nerves are stretched or compressed. These neurological symptoms are less common but important to recognize as they may signal more severe injury 12.

Additional Associated Signs

• Muscle spasms around the joint
• A feeling of instability or “dead arm”
• Sometimes, a “clunk” as the joint comes out of or back into place

Prompt recognition of these symptoms is crucial, as delayed diagnosis—especially with rarer forms like posterior dislocation—can worsen outcomes 2.

Types of Dislocated Shoulder

Not all shoulder dislocations are the same. Understanding the specific type helps guide treatment and predict risks of recurrence or complications. The direction in which the upper arm bone (humerus) slips out of the socket (glenoid) defines the type.

Type	Direction of Displacement	Frequency	Source(s)
Anterior	Forward (toward chest)	Most common	2 3 8 12
Posterior	Backward (toward back)	Rare	2 4 7
Inferior	Downward	Very rare	2
Multidirectional	Multiple directions	Extremely rare	1

Table 2: Dislocation Types

Anterior Dislocation

This is by far the most frequent type, accounting for up to 95% of cases. The humeral head is displaced forward, often after a fall on an outstretched arm or a blow to the shoulder. Anterior dislocations are common in contact sports and accidents 2 3 8 12.

Associated Lesions

• Bankart lesion: A tear of the labrum (rim of cartilage) at the front of the shoulder socket.
• Hill-Sachs lesion: A compression fracture on the back of the humeral head 3 5 6.

These injuries increase with repeated dislocations and can drive the need for surgery 3 5 11.

Posterior Dislocation

This type is much less common, making up about 2–4% of shoulder dislocations. Posterior dislocations often result from seizures, electrical shocks, or high-energy trauma. Diagnosis is frequently delayed, which can lead to worse outcomes and more severe joint damage 2 4 7.

Special Considerations

• May be accompanied by fractures, particularly in chronic or neglected cases.
• Classification can be based on bone loss and associated fractures, which guides treatment options 4.

Inferior (Luxatio Erecta) and Multidirectional Dislocations

Inferior dislocation is extremely rare and usually results from a forceful downward pull on the arm. Multidirectional dislocation refers to instability in more than one direction and is a rare, complex condition often associated with generalized ligament laxity 1 2.

Causes of Dislocated Shoulder

Understanding why shoulders dislocate can help prevent injuries and inform treatment. Causes can be divided into traumatic events, repetitive strain, and underlying joint looseness.

Cause Type	Examples	At-Risk Groups	Source(s)
Trauma	Falls, blows, sports injuries, car accidents	Young adults, males	2 3 8 12
Seizures/Electric Shock	Violent muscle contractions	Seizure patients	2 7
Repetitive Overuse	Throwing sports, overhead motions	Athletes, laborers	3 5
Joint Laxity	Congenital or acquired looseness	Some young people	5 6 11

Table 3: Common Causes

Traumatic Causes

The overwhelming majority of shoulder dislocations are traumatic. A forceful impact—such as falling onto an outstretched arm or a direct blow during sports—can drive the humeral head out of its socket. This is especially common in young, active males participating in contact or overhead sports 3 8 12.

Seizures and Electric Shock

Posterior shoulder dislocations are most often triggered by violent, uncoordinated muscle contractions during seizures or electrical injuries. These forces pull the head of the humerus backward, which is opposite the more common anterior direction 2 7.

Repetitive Overuse and Instability

Repeated motions, especially those involving overhead activity (e.g., throwing, swimming), can gradually stretch the joint capsule and ligaments, leading to instability and eventual dislocation. This is a frequent issue in athletes and manual laborers 3 5.

Joint Laxity and Anatomical Factors

Some individuals have naturally looser ligaments or a shallow shoulder socket, making them more prone to dislocation with minimal trauma or even during routine activities. Generalized ligamentous laxity can also contribute to multidirectional instability 5 6 11.

Complications and Recurrence

Once a shoulder has dislocated, it becomes more susceptible to future dislocations, particularly in young, active individuals. Recurrent instability is often linked to associated injuries like Bankart or Hill-Sachs lesions, and to inadequate healing of the capsule and ligaments 3 5 6 11.

Treatment of Dislocated Shoulder

Treating a dislocated shoulder is about more than just “popping it back in.” The best approach depends on the type, severity, patient activity level, and associated injuries. Treatment may range from simple reduction and physiotherapy to advanced surgical reconstruction.

Approach	When Used	Main Goal	Source(s)
Closed Reduction	Initial management for most dislocations	Restore joint alignment	2 9 12
Immobilization	After reduction, especially first dislocation	Allow healing, prevent recurrence	8 12
Surgical Repair	Recurrent, complex, or failed non-surgical cases	Stabilize joint, repair damage	5 6 8 11
Arthroplasty	Severe/chronic cases with bone loss/arthritis	Replace damaged joint	4 9 10
Physical Therapy	All cases, especially after immobilization	Restore strength and motion	8 12

Table 4: Treatment Modalities

Emergency Management: Reduction

The immediate goal is to reduce (relocate) the shoulder joint. Multiple techniques exist, but no single “best” method. Success rates are similar, but intra-articular lidocaine can reduce pain and complications compared to intravenous sedation 12. Closed reduction is usually performed, followed by confirmation with imaging 2 9 12.

Immobilization

After reduction, the arm is typically immobilized in a sling for a short period. Some evidence suggests immobilization in external rotation may lower recurrence rates, while internal rotation (traditional sling) is less effective 12. Prolonged immobilization is avoided to prevent stiffness.

Surgical Versus Non-Surgical Treatment

Non-Surgical

Most first-time anterior dislocations in older adults or less active individuals can be managed non-surgically—with reduction, brief immobilization, and physical therapy. However, recurrence rates are higher in young, active adults, especially males 8 12.

Surgical

• Young, active patients with first-time traumatic dislocation: Surgery significantly reduces recurrence and improves function compared to non-surgical care 8 11 12.
• Recurrent dislocations or significant structural injury: Surgery becomes the preferred option. Procedures may include arthroscopic Bankart repair, open stabilization (e.g., Bristow-Latarjet), or capsular repair 5 6 11.
• Associated bone loss or chronic instability: More complex reconstructions, bone grafting, or even joint replacement (arthroplasty) may be required, especially in neglected posterior dislocations with extensive damage 4 9 10.

Special Cases: Posterior and Complex Dislocations

Chronic or posterior dislocations often require open reduction or replacement procedures, guided by the degree of bone loss, malunion, and associated injuries 4 9 10. Arthroplasty (joint replacement) is increasingly used for severe cases, particularly when joint surfaces are destroyed 4 9 10.

Rehabilitation and Outcomes

Physical therapy is vital for all patients to restore strength, range of motion, and function. Early movement, once pain allows, is encouraged to prevent stiffness. Full return to sports or physical work is usually permitted when strength and motion have returned to near-normal levels, though the risk of recurrence remains higher for athletes 12.

Complications and Long-Term Considerations

• Recurrent instability (especially in young, active patients)
• Arthropathy (joint arthritis) is more likely after repeated dislocations or delayed diagnosis, especially in posterior cases 1 2
• Nerve injury (rare but serious)
• Failure of surgical repair, though reoperation can still yield good results 5

Conclusion

A dislocated shoulder is a disruptive and sometimes recurring injury, but with early recognition and evidence-based treatment, most people regain good function. Here’s a summary of key points:

• Symptoms: Intense shoulder pain, visible deformity, inability to move the arm, and swelling are classic signs 2 12.
• Types: Most dislocations are anterior; posterior and inferior types are less common but often more complex 2 4 7.
• Causes: Acute trauma is the main cause, but seizures, overuse, and joint laxity also contribute 2 3 5 8 12.
• Treatment: Early reduction, appropriate immobilization, and physical therapy are standard. Surgery is favored for young, active patients and those with recurrent or complex injuries 5 6 8 11 12.

Key Takeaways:

• Prompt diagnosis and reduction are crucial for the best outcomes.
• Young adults, especially athletes, are at higher risk for recurrence and may benefit from surgery after a first dislocation.
• Posterior dislocations are often missed—awareness is key, especially after seizures or electrical injuries.
• Rehabilitation and proper follow-up are essential to restore function and avoid long-term complications.

Understanding your injury and the full range of treatment options empowers you to make informed decisions about your recovery and long-term shoulder health.