Shoulder Dislocation –
Causes, Symptoms & Treatment

The shoulder is the most mobile joint in the human body. Its wide range of motion allows us to lift, reach, and rotate the arm — but this mobility also makes it more prone to dislocation than any other joint.

Shoulder dislocation occurs when the ball of the upper arm bone (humeral head) comes out of the socket of the shoulder blade (glenoid). The glenoid is part of the scapula and forms a shallow cup that helps the ball stay in place, supported by ligaments and muscles.

In fact, 50% of all major joint dislocations involve the shoulder, most often in younger, active people. Every year, around 12 out of every 100,000 people experience a first-time shoulder dislocation.

Types of Shoulder Dislocation

  • Anterior dislocation (≈95% of cases): the ball pops out the front of the socket. Common after a fall, tackle, or sudden external rotation of the arm.
  • Posterior dislocation: rarer (≈4%), usually from seizures, electric shock, or heavy impact forcing the arm backward.
  • Inferior dislocation: extremely rare; the arm may appear locked above the head.

Causes and Risk Factors

Dislocation can occur from a traumatic injury or less commonly from shoulder instability due to loose ligaments or prior injury. Typical causes include:

  • Falling onto an outstretched arm or directly onto the shoulder
  • Sporting injuries such as tackles, collisions, or overhead throwing
  • Previous dislocations that have stretched or torn supporting tissues (making recurrence more likely)
  • Congenital laxity (naturally loose joints)

Common Symptoms

  • Severe, sudden shoulder pain and inability to move the arm
  • Visible deformity – shoulder appears out of place or flattened
  • Muscle spasm around the joint
  • Numbness or tingling due to nerve stretch or compression

Diagnosis

A specialist will assess your shoulder’s shape, alignment, and range of motion. Imaging helps confirm the direction and severity:

  • X-rays – confirm dislocation, look for fractures
  • MRI – detect soft tissue injuries such as labral tears (Bankart lesion) or Hill-Sachs defects
  • CT scan – evaluate bone loss in recurrent cases

Immediate Treatment

Prompt management helps prevent long-term instability or nerve injury.

  • Closed reduction: the shoulder is gently repositioned (“reduced”) by a trained clinician under sedation or anaesthesia.
  • Immobilisation: a sling is worn for 2–3 weeks to allow healing of soft tissues.
  • Pain control: medications and icing reduce pain and swelling.

Rehabilitation & Recovery

After immobilisation, physiotherapy focuses on restoring movement, strength, and joint stability. A staged program includes:

  • Gradual range-of-motion exercises (weeks 2–6)
  • Strengthening rotator cuff and scapular muscles (weeks 6–12)
  • Return to sport/work after medical clearance, typically 12–16 weeks for first dislocations

Treatment Options: Non-operative vs Arthroscopic Stabilisation

Evidence-based comparison to guide decisions after a first-time or recurrent shoulder dislocation
AspectNon-operative CareArthroscopic Stabilisation
GoalReduce pain/swelling; restore range; strengthen dynamic stabilisers; protect healing.Restore static stability (labrum/capsule ± bone); reduce recurrence; protect cartilage.
IndicationsFirst dislocation with lower recurrence risk; minimal bone loss; lower-demand sport.High recurrence risk (e.g., young contact/overhead athletes), recurrent instability, Bankart tear, engaging Hill-Sachs, or glenoid bone loss.
What it involvesSling 2–3 wks → graded ROM → rotator cuff & scapular strengthening (12–16 wks).Arthroscopy with labral repair/capsular plication (Bankart) or bone procedures (e.g., Latarjet) for significant bone loss.
ProsNo surgical risks; quicker early recovery; suitable for many first-time cases.Lower recurrence in high-risk groups; earlier safe return to contact/overhead sports in selected cases.
LimitationsHigher recurrence in young/contact athletes; possible ongoing apprehension.Surgical/anesthetic risks; rehab still required; small risk of stiffness or nerve irritation.
Typical timelineReturn to non-contact sport/work ≈ 12–16 wks when pain-free with symmetric control.Run/erg ~6–8 wks; non-contact sport ~12–16 wks; contact/collision only after strength & control symmetrical (often 4–6+ months; surgeon-guided).
Best forLower-risk patients, non-collision sports, minimal structural damage.Young, high-demand athletes; recurrent instability; structural lesions or bone loss.

Bone loss matters: Significant glenoid bone loss or engaging Hill-Sachs lesions may require a bone procedure (e.g., Latarjet) rather than soft-tissue repair alone. We tailor the plan after MRI/CT and examination.

Recurrent dislocations may need surgical stabilisation, such as a shoulder arthroscopy with labral repair or bone augmentation (Latarjet procedure) depending on findings.

Prognosis

Most patients recover well with early reduction, rest, and structured physiotherapy. However, younger athletes—especially males under 25—have a higher recurrence risk (up to 70–90%) if treated non-operatively after a first dislocation.

Specialist evaluation helps determine whether early surgical repair may reduce future instability and protect the joint from long-term wear.

Further Reading and References