Shoulder
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AC Joint Separation

AC Joint Separation

In This Article

What is an AC Joint Separation?

AC joint separation (or AC joint sprain) involves injury to the ligaments connecting the acromion and clavicle, resulting in varying degrees of joint displacement.

  • Ligamentous injury at the acromioclavicular joint
  • Causes shoulder deformity and pain

Overview of the Condition

Often caused by a fall directly onto the shoulder. Severity is graded from mild (Type I) to severe (Type VI) depending on ligament damage and displacement.

Symptoms

  • Pain and tenderness over the AC joint
  • Bump or prominence on the top of the shoulder
  • Limited shoulder movement

Causes

Direct impact onto the shoulder (e.g., falling on a hard surface) injures the AC and coracoclavicular ligaments, causing separation.

Diagnosis

Physical exam reveals tenderness over the AC joint. X-rays with weights may show displacement. MRI clarifies ligament damage if needed.

Treatment Options

  • Sling and rest for mild injuries
  • Surgical reconstruction of ligaments for severe separations
  • Physical therapy for rehabilitation

Conservative Management

Mild to moderate AC separations often heal with immobilization, ice, and NSAIDs. Early mobilization prevents stiffness.

Rehabilitation Exercises

  1. Passive range-of-motion initially
  2. Gradual rotator cuff and scapular strengthening
  3. Sports-specific drills when pain-free

Surgical Options

Severe separations may require ligament reconstruction using grafts or fixation devices to restore AC joint alignment.

Anatomy Overview

The AC joint is supported by the acromioclavicular and coracoclavicular ligaments. Disruption leads to varying degrees of clavicle displacement.

Affected Areas

  • Acromioclavicular joint
  • Coracoclavicular ligaments

Frequently Asked Questions

QuestionAnswerCan I return to normal activities after an AC separation?Yes, many people regain full function, especially with lower-grade injuries.Does a bump on the shoulder remain?Some cases show a residual bump but may not affect function.

Prevention Strategies

  • Use proper protective equipment in sports
  • Avoid direct falls onto the shoulder
  • Maintain strong upper body and good shoulder mechanics

Related Conditions

  • Clavicle fractures
  • AC joint arthritis

Additional Treatments

Pain control with NSAIDs or injections, followed by progressive rehabilitation.

A Quick, Clear First Step Toward Joint Pain Relief

In under 2 minutes, OrthoCheck gives you a likely diagnosis—no appointment needed. If follow-up care is recommended, we’ll connect you with a top-rated orthopedic specialist near you.