Posterior Shoulder Dislocation

Posterior shoulder dislocation is a rare but frequently missed injury where the humeral head displaces behind the glenoid. It accounts for fewer than 5% of all shoulder dislocations and is classically associated with seizures, electrocution, and direct anterior shoulder trauma.

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Typical Recovery Time

6–12 weeks for uncomplicated cases; longer if surgery required

Symptoms

•Arm held in internal rotation and adduction
•Inability to externally rotate the arm
•Flattened anterior shoulder contour
•Posterior shoulder fullness
•Severe pain and limited motion

Common Causes

•Seizure activity (most common cause)
•Electric shock or lightning strike
•Direct blow to the anterior shoulder
•Fall on an outstretched hand with axial loading
•High-energy trauma

Treatment Options

1Closed reduction under sedation (emergent)

2Immobilization in external rotation

3Physical therapy after reduction

4Surgical stabilization for recurrent or locked dislocations

5Reverse Hill-Sachs (McLaughlin procedure) for large defects

When to See a Doctor

Posterior dislocation is a medical emergency — seek immediate evaluation. It is often missed on standard X-rays; axillary view is essential.

Frequently Asked Questions

What is a posterior shoulder dislocation?

A posterior shoulder dislocation occurs when the ball of the shoulder moves out of the socket toward the back. It is less common than anterior dislocations. This injury can cause pain and limited movement.

What causes a posterior shoulder dislocation?

It can occur from trauma, seizures, or electrical injuries. Falls or forceful impacts can also cause this injury. It is sometimes missed because it is less common.

What are the symptoms?

Symptoms include shoulder pain, difficulty rotating the arm outward, and limited motion. The arm may feel locked in place. Swelling and discomfort are common.

How is it treated?

Treatment involves reducing the dislocation and then stabilizing the shoulder. Physical therapy is used to restore strength and motion. Surgery may be needed if instability persists.

When can I return to sports?

Return depends on stability, strength, and healing. Non-contact activities may resume sooner than contact sports. A gradual return is important to reduce reinjury risk.