Acromioclavicular Joint Pain

The acromioclavicular (AC) joint is the area where the shoulder blade (scapula) and the collarbone (clavicle) meet. The uppermost part of the shoulder blade called the acromion, is connected to the collarbone by sturdy ligaments, which form the AC joint. An injury to the AC joint affects the joint where the shoulder blade connects to the collarbone, usually presenting as a sprain. Such injuries commonly occur due to blunt force trauma that separates the tendons.

Acromioclavicular Joint Stabilizing Structures

• Capsular ligaments: Known as the acromioclavicular ligaments, these comprise upper and lower components that prevent the joint from separating horizontally.
• Extracapsular stabilizers: These include ligaments connecting the coracoid process of the scapula to the clavicle (coracoclavicular ligaments) as well as the acromion (coracoacromial ligaments). They repel vertical forces that could separate the joint.
• Muscular attachments: The deltoid muscle on the outer shoulder, along with the trapezius muscle located in the neck and upper back, contribute to the stabilization of the AC joint.

Injuries to the AC joint, especially the ligaments, can lead to instability or separation of the joint (shoulder separation). This results in pain, discomfort, and limited shoulder function.

Symptoms

The intensity of symptoms can differ depending on the injury’s severity, and may include:

• Pain in the shoulder
• Sensitivity when the shoulder is touched
• Bruising
• Swelling
• Change in the shoulder’s shape
• A visible bulge over the shoulder
• Drooping of the shoulder
• Elevation of the collarbone
• Reduced shoulder mobility

Causes

An acromioclavicular joint pain typically results from injuries or accidents that separate the joint. These can occur in the following ways:

• Falling directly onto the shoulder
• Falling onto an extended arm
• Taking a direct hit to the shoulder

Risk Factors

Factors likely to contribute to AC joint pain are:

• Engaging in contact sports
• Involvement in activities with a higher risk of falls, like biking, skiing, or skating
• Weightlifting
• Physically demanding jobs

Diagnosis

To diagnose an acromioclavicular joint problem, our doctors at The Joint Pain Clinic will first assess your symptoms and medical history. They will also conduct a comprehensive physical exam to evaluate the joint’s range of motion, stability, strength, and blood circulation.

Additional diagnostic tests that may be ordered include an X-ray, MRI, CT scan, or ultrasound for a more detailed assessment of the joint.

Our Treatment Options

Mostly, conservative treatment approaches are highly effective in managing AC joint pain. They include:

• Resting the joint for an extended period.
• Applying a cold pack regularly to ease discomfort and swelling.
• Taking anti-inflammatory drugs.
• Engaging in physical therapy to strengthen shoulder muscles and boost range of motion.