Understanding AC Joint Arthritis: Causes, Symptoms, and Treatment

ac joint arthritis

Shoulder pain can be a debilitating experience, and when it’s linked to AC joint arthritis, it can significantly impact your daily life. AC (acromioclavicular) joint arthritis is a common cause of shoulder discomfort, especially in individuals who engage in repetitive overhead movements or sports activities. This condition can affect people of all ages and backgrounds, making it essential to gain a thorough understanding of its causes, symptoms, and effective management strategies. In this blog, we will delve into the world of AC joint arthritis, exploring its origins, the signs that might indicate its presence, and the various options available for relief and improved quality of life. So, let’s get started!

What is AC Joint Arthritis?

What is AC Joint ArthritisAC joint arthritis, or acromioclavicular joint arthritis, refers to the degeneration of the acromioclavicular joint in the shoulder. The acromioclavicular joint is located at the top of the shoulder, where the acromion (a part of the scapula or shoulder blade) meets the clavicle (collarbone). This joint is responsible for various shoulder movements and is crucial for proper shoulder function.

Arthritis in the AC joint occurs when the cartilage that covers the joint surfaces starts to wear down or become damaged. Cartilage is essential for smooth joint movement, and its deterioration can result in pain, inflammation, and reduced mobility. AC joint arthritis is typically characterized by symptoms like:

  • Pain: Individuals with AC joint arthritis often experience pain at the top of the shoulder. The pain can vary in intensity and may worsen with activities that involve lifting the arm or moving the shoulder.
  • Swelling: Inflammation of the AC joint can lead to swelling or tenderness in the shoulder area.
  • Limited Range of Motion: As the arthritis progresses, the range of motion in the shoulder may become restricted, making it challenging to perform overhead movements or certain activities.
  • Crepitus: Some people with AC joint arthritis may hear or feel a grinding or popping sensation in the shoulder when moving it.
  • Weakness: Muscle weakness around the shoulder can occur due to pain and limited mobility.

AC joint arthritis can develop due to various factors, including aging, prior shoulder injuries, overuse, or repetitive strain on the joint. It can also be associated with other shoulder conditions.

Causes of AC Joint Arthritis

Causes of AC Joint ArthritisUnderstanding the underlying causes of AC joint arthritis can help individuals manage the condition effectively.

  • Age-Related Wear and Tear: The most common cause of AC joint arthritis is the natural aging process. Over time, the cartilage that covers the joint surfaces can deteriorate, leading to friction and inflammation. This wear and tear is more likely to occur in individuals over the age of 50.
  • Prior Shoulder Injuries: A history of shoulder injuries or trauma can contribute to the development of AC joint arthritis. Injuries such as dislocations, fractures, or repeated shoulder separations can damage the joint’s cartilage and increase the risk of arthritis.
  • Overuse or Repetitive Strain: Activities that involve repetitive overhead arm movements, such as weightlifting, throwing, or certain sports, can strain the AC joint. Over time, this repetitive stress may lead to joint inflammation and arthritis.
  • Ligament Sprains: Injuries to the ligaments supporting the AC joint, often caused by falls or direct blows to the shoulder, can disrupt the joint’s stability. Instability in the joint can accelerate the degeneration of the cartilage.
  • Occupational Factors: Certain occupations that require heavy lifting or overhead work, such as construction or manual labor, can increase the risk of AC joint arthritis due to continuous stress on the joint.
  • Genetic Predisposition: Some individuals may have a genetic predisposition to joint problems, including AC joint arthritis. Family history can play a role in the development of this condition.
  • Inflammatory Conditions: Inflammatory joint diseases like rheumatoid arthritis or ankylosing spondylitis can affect the AC joint, leading to inflammation and arthritis.
  • Unresolved Shoulder Injuries: Failure to adequately treat and rehabilitate previous shoulder injuries can leave the joint vulnerable to degeneration and arthritis.
  • Infection or Septic Arthritis: Although rare, bacterial infections can affect the AC joint, causing inflammation and potentially leading to arthritis if not treated promptly.

Understanding the specific cause of AC joint arthritis is essential for developing an appropriate treatment plan. Early diagnosis and treatment can help individuals with AC joint arthritis manage their symptoms effectively and maintain a good quality of life.

Exercises for AC Joint Arthritis

Exercise for AC joint arthritis can be an essential part of managing this condition and reducing pain and stiffness in the affected shoulder. These exercises should be done under the guidance of a healthcare professional or physical therapist, especially if you’re new to them or have specific limitations. Here are some exercises that can help:

Pendulum Exercises

These gentle pendulum exercises can help improve shoulder mobility without putting too much stress on the AC joint.

    • Stand with your unaffected hand resting on a table or chair.
    • Bend at the waist so your affected arm hangs freely.
    • Gently swing your affected arm in small circles, both clockwise and counterclockwise.
    • Start with 10-15 circles in each direction and gradually increase as tolerated.

Shoulder Blade Squeezes

These exercises help strengthen the muscles around the shoulder blade, providing better support to the AC joint.

    • Sit or stand with your arms by your sides.
    • Squeeze your shoulder blades together as if you’re trying to hold a pencil between them.
    • Hold this position for 5 seconds, then relax.
    • Repeat this exercise for 10-15 repetitions.

Range of Motion (ROM) Exercises

Gentle range of motion exercises can help maintain flexibility in the shoulder joint.

    • Stand or sit comfortably.
    • Gently raise your affected arm forward, then out to the side, and finally behind your back as far as comfortable.
    • Repeat this exercise for 10-15 repetitions in each direction.

Isometric Exercises

Isometric exercises help build strength in the shoulder without causing excessive movement.

    • Hold a small ball, rolled-up towel, or resistance band between your hands.
    • Gently press your hands together while keeping your elbows bent at 90 degrees.
    • Hold the contraction for 5-10 seconds, then relax.
    • Repeat this exercise 10-15 times.

Assisted Stretching

Gentle-assisted stretching exercises can help maintain shoulder flexibility.

    • Hold onto a sturdy surface with your unaffected hand.
    • Use your unaffected hand to gently stretch your affected arm across your chest.
    • Hold the stretch for 15-30 seconds and repeat several times.

Wall Angels

Wall angel exercises can improve shoulder mobility and strengthen the muscles around the shoulder blades.

    • Stand with your back against a wall, feet about 6 inches away from the wall.
    • Bend your elbows at a 90-degree angle, so your upper arms are parallel to the floor.
    • Slowly slide your arms up the wall as far as you can without pain, keeping your elbows and wrists in contact with the wall.
    • Hold this position for a few seconds, then slide your arms back down.
    • Perform 10-15 repetitions.

Remember to start these exercises gently and gradually increase the intensity as your shoulder allows. If you experience increased pain or discomfort, stop the exercise immediately and consult your healthcare provider or physical therapist. They can provide you with a personalized exercise plan tailored to your specific condition and monitor your progress to ensure you’re getting the most benefit from your exercises while minimizing any risk of injury.

When to Seek Treatment?

When to Seek TreatmentDetermining when to seek treatment for AC joint arthritis is crucial to managing your condition effectively. Here are some key indicators:

  • Persistent Pain: If you experience persistent shoulder pain, especially during activities or at rest, it’s essential to seek medical evaluation.
  • Limited Range of Motion: When you notice a significant decrease in the range of motion in your shoulder joint, it’s a sign that you should consult a healthcare professional.
  • Difficulty with Daily Activities: If AC joint arthritis starts affecting your ability to perform daily tasks, such as reaching overhead, lifting objects, or getting dressed, it’s time to seek help.
  • Pain Interfering with Sleep: If your shoulder pain disrupts your sleep patterns or prevents you from getting a good night’s rest, it’s a clear indication to seek treatment.
  • Swelling or Inflammation: If you notice swelling, redness, or warmth around your AC joint, it may indicate inflammation and medical attention is warranted.
  • Persistent Discomfort Despite Rest: If resting your shoulder does not alleviate the pain and discomfort, consult a healthcare provider.
  • Numbness or Tingling: If you experience numbness, tingling, or weakness in your arm or hand in addition to shoulder pain, it may indicate nerve involvement, requiring prompt evaluation.
  • Progressive Symptoms: If your symptoms worsen over time, don’t wait to seek medical advice. Early intervention can prevent further deterioration.
  • Previous Shoulder Issues: If you have a history of shoulder problems or injuries and notice recurring symptoms, consult a healthcare professional to rule out AC joint arthritis.
  • Impact on Quality of Life: If AC joint arthritis affects your quality of life, causing emotional distress or limiting your ability to participate in activities you enjoy, it’s time to consider treatment options.

Keep in mind that early diagnosis and intervention often lead to better outcomes. If you experience any of these signs or symptoms, don’t hesitate to reach out to a healthcare provider for a proper evaluation and guidance on managing AC joint arthritis.



In conclusion, AC joint arthritis can be a painful condition that affects shoulder function and quality of life. However, with the right treatment and management strategies, many individuals can find relief from pain and regain functionality. Whether through conservative measures like physical therapy and medications or, in more severe cases, surgical intervention, there are options available to address AC joint arthritis. Early diagnosis and a personalized treatment plan tailored to your needs are key to achieving the best outcomes.If you’re experiencing Shoulder pain, physical therapy for shoulder pain at PhysioMantra can help: Book an online physical therapy session.