Shoulder Condition Guide
Acromioclavicular (AC) Joint Arthritis
The acromioclavicular (AC) joint is located at the top of the shoulder where the collarbone (clavicle) meets the shoulder blade (acromion). This joint plays a key role in allowing the arm to move overhead and across the body.
AC joint arthritis occurs when the cartilage within this joint wears down over time, leading to pain, inflammation, and reduced function. It is a common source of shoulder pain, especially in individuals who perform repetitive overhead movements, weightlifting, or manual labor.
Symptoms often include pain at the top of the shoulder, tenderness, and discomfort when reaching across the body, lifting, or performing pressing movements.
Quick safety note: If you experience sharp pain, swelling, or loss of strength, avoid aggravating activities and consult your provider.
Understanding AC Joint Arthritis
Symptoms, Causes & Treatment
AC joint arthritis is typically caused by gradual wear and tear (osteoarthritis), though it can also develop after injury or repetitive stress to the joint. Many patients may have imaging findings without symptoms, but others develop persistent pain that affects daily activity.
Common symptoms include:
• Pain on the top of the shoulder
• Pain with cross-body movements (e.g., reaching across chest)
• Discomfort with lifting or overhead activity
• Tenderness or swelling at the joint
Common causes include:
• Age-related cartilage wear
• Repetitive overhead or heavy lifting activities
• Previous shoulder injuries or separations
Treatment options:
Most cases are treated conservatively with activity modification, physical therapy, anti-inflammatory medications, and corticosteroid injections. In more severe or persistent cases, surgical intervention may be considered.
Patient Education Resource
AC Joint Arthritis Guide
The resource below provides additional details on anatomy, symptoms, and treatment options for AC joint arthritis.
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