Acromioclavicular Joint Arthritis (AC Joint Arthritis)

Acromioclavicular joint arthritis, also called AC joint arthrosis, is a degeneration of the joint at the top of the shoulder where the acromion meets the clavicle. Read on to learn more about AC joint arthritis symptoms, causes, and treatment from Atlanta's premier shoulder physicians.

What is Acromioclavicular Joint Arthritis?

AC arthritis is a shoulder condition that affects the joint where the collarbone (clavicle) meets the shoulder blade (acromion). Your shoulder is a complex structure of bones and joints that enables your arm's movement. The acromioclavicular joint is one critical component in this system, allowing for smooth arm movements like reaching and lifting.

In a healthy joint, the surfaces of these bones are covered by a protective layer called cartilage, which ensures smooth motion. However, in AC joint arthritis, this cartilage gradually wears away. As a result, the bones can start to rub against each other, leading to pain, stiffness, and swelling. Patients often experience aching discomfort in the top of their shoulder, especially when performing overhead motions. Visible changes may occur, such as a noticeable bump or deformity at the shoulder's tip. AC joint arthritis can hinder everyday activities like lifting or carrying objects, but various treatments are available to alleviate pain and enhance functionality.

What Causes AC Joint Arthrosis?

AC joint arthrosis can be caused by any of the following factors:

  • Joint Injuries: One common cause is injuries to the AC joint. When you injure your shoulder, like during a bad fall or surgery, it can harm the AC joint. Even if you don't feel it right away, this can lead to arthritis in the long run. For instance, if you had a shoulder injury in the past, like a shoulder separation, it increases the chance of developing AC joint arthritis later on.
  • Overusing Your Shoulder: People who do a lot of heavy lifting or play sports that strain the shoulder, like hockey, can put extra stress on their AC joint. Over time, this stress can lead to arthritis.
  • Birth and Health Conditions: Certain health conditions or illnesses can increase the risk of AC arthritis.
  • Aging: As we age, our joints naturally wear down, making AC joint arthritis more common among older individuals

AC Joint Arthritis Symptoms

Wondering if you might have AC arthritis? Here are some AC joint arthritis symptoms to look out for:

  • Shoulder Pain and Tenderness: One of the first signs is feeling pain and tenderness at the top of your shoulder, right around the joint. Even sleeping on that side can become painful. Sometimes, if you've had an old injury there, you might hear a snap or click when you move your shoulder, and the area around the AC joint might stick out more than usual.
  • Decreased Shoulder Movement: You may notice that your shoulder doesn't move as freely as it used to. Simple actions like reaching across your body or putting on a car seatbelt can become a bit tricky.
  • Pain with Specific Movements: AC joint arthritis can make certain motions quite painful. Things like doing a bench press, push-ups, reaching behind your back, or reaching overhead may cause discomfort.
  • Joint Tenderness and Pain: The front and top part of your shoulder, where the shoulder blade and collarbone meet, might feel tender and painful. If the pain is more towards the back of your shoulder, that could be a sign of arthritis in the glenohumeral joint, which is the shoulder's ball-and-socket joint.

It's important to remember that these symptoms can gradually get worse over time, and the pain might come and go. If you notice these signs, it's a good idea to contact our shoulder physicians for guidance on managing and treating AC joint arthritis.

How Is Acromioclavicular Arthrosis Diagnosed?

Doctors typically diagnose AC joint arthrosis through a series of evaluations. The initial step involves a thorough physical examination. During this examination, your doctor carefully assesses the area surrounding the AC joint, looking for signs of tenderness and discomfort. A key diagnostic sign is the presence of pain when pressure is applied to the joint. This tenderness and pain in response to compression can strongly indicate AC joint arthritis.

In addition to the physical examination and pain assessment, your doctor will order imaging of the AC joint. Digital imaging offers valuable insights, revealing signs of joint degeneration such as joint narrowing and the presence of bone spurs around the joint. These findings, when combined with the clinical evaluation, help us accurately diagnose AC arthritis. This comprehensive approach ensures that the cause of your shoulder pain is identified correctly, so we can recommend the best AC arthritis treatment for your specific needs.

AC Joint Arthritis Treatment Options

Every case of AC joint arthritis is different, and we have non-surgical and surgical treatments available to our patients.

Non-Surgical AC Arthritis Treatment

The first-line approach to addressing AC joint arthritis typically involves rest and the use of anti-inflammatory drugs like aspirin or ibuprofen. Your physician will likely prescribe physical therapy treatment and exercises to perform at home. If the pain persists, a cortisone injection into the joint may be recommended. Cortisone is a potent medication that reduces inflammation and alleviates pain. While its effects are often temporary, it can provide highly effective short-term relief.

AC Joint Arthritis Surgery

When non-surgical treatments are not enough to alleviate your AC joint arthritis pain, surgical intervention may be recommended. The most common surgical procedure for AC joint arthritis is known as distal clavicle excision or resection arthroplasty.

In an AC joint arthritis surgery, a skilled surgeon removes a small portion of the end of the clavicle (collarbone). This precise removal creates a space between the acromion, the part of the shoulder blade that meets your shoulder, and the trimmed end of the clavicle where the joint used to exist. Typically, only a small segment, less than one centimeter, is removed. As your body heals following the surgery, the missing joint is gradually replaced by scar tissue. This scar tissue permits movement while preventing the bone ends from rubbing against each other. By creating this space and facilitating scar tissue formation, resection arthroplasty aims to restore comfort and functionality to your AC joint.

If you're struggling with AC arthritis pain, don't wait. Schedule an appointment with a Resurgens shoulder physician today to get moving again.

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