AC Joint Sprain
Region: Shoulder
An AC joint sprain, also called a separated shoulder, occurs when the ligaments connecting the collarbone (clavicle) to the shoulder blade are stretched or torn. It commonly happens after a direct hit or fall onto the shoulder in contact sports.
What is an AC joint sprain?
An AC joint sprain, also called a separated shoulder, occurs when the ligaments connecting the collarbone (clavicle) to the shoulder blade are stretched or torn. It commonly happens after a direct hit or fall onto the shoulder in contact sports.
Symptoms
  • Pain at the top of the shoulder
  • Swelling or bruising
  • Pain lifting the arm
  • Shoulder weakness
  • Tenderness over the AC joint
  • Visible bump on the shoulder
What does an AC joint sprain feel like?
  • Sharp pain after impact
  • Pain when reaching across the body
  • Shoulder feels sore or unstable
  • Pain carrying heavy objects
  • Discomfort with overhead movement
What are common causes of an AC joint sprain?
  • Falling directly onto the shoulder
  • Football or hockey collisions
  • Wrestling injuries
  • Cycling or skating falls
  • Direct impact during contact sports
Self check
  • Pain at the top of the shoulder after a fall or hit
  • Pain when lifting the arm
  • Tenderness over the collarbone area
  • Pain reaching across your chest
  • Visible bump near the shoulder
Educational only — not a medical diagnosis.
What to do now
  • Rest the shoulder
  • Apply ice for 15–20 minutes
  • Avoid overhead activity
  • Use a sling if recommended
  • Begin gentle motion as pain improves
  • Seek evaluation if pain or deformity is significant
Red flags
  • Severe deformity or large bump
  • Inability to move the arm
  • Numbness or tingling
  • Significant swelling or bruising
  • Persistent instability
  • Pain not improving with rest
Recovery tips
  • Gradually restore shoulder mobility
  • Strengthen the shoulder and upper back
  • Avoid returning to contact sports too early
  • Maintain good posture during recovery
  • Progress activity slowly as pain decreases
Educational only. Not a medical diagnosis.
Tracks symptoms over time (not a diagnosis).