AC Joint Resection

Arthroscopic acromioclavicular (AC) joint resection is a minimally invasive surgical procedure used to treat arthritis or degenerative conditions affecting the AC joint. This surgery is particularly beneficial for patients suffering from persistent pain or dysfunction in the shoulder, especially when other treatments like physical therapy or medications have not provided relief.

How Common It Is and Who Gets It? (Epidemiology)

AC joint arthritis and related conditions are common, especially in individuals over the age of 40 or those who have experienced trauma or overuse of the shoulder. Athletes, especially those involved in overhead sports or heavy lifting, are also at higher risk. This condition can significantly impair shoulder function, making activities such as reaching overhead or lifting weights painful.

Why It Happens – Causes (Etiology and Pathophysiology)

The AC joint connects the clavicle (collarbone) with the acromion (part of the shoulder blade). It allows the shoulder to move in coordination with the rest of the arm. Over time, trauma, repetitive overhead activities, or age-related degeneration can cause inflammation, pain, and eventually arthritis in the joint. In severe cases, bone spurs or osteophytes can develop, contributing to pain and limiting movement.

How the Body Part Normally Works? (Relevant Anatomy)

The AC joint is located where the clavicle meets the acromion. It plays a key role in the movement of the shoulder, particularly with overhead motions and arm rotation. Ligaments and the surrounding capsule help stabilize the joint and facilitate smooth motion. Damage to the AC joint can limit the shoulder’s ability to move freely, resulting in pain and dysfunction.

What You Might Feel – Symptoms (Clinical Presentation)

The most common symptoms of AC joint arthritis include:

• Pain: Pain localized at the top of the shoulder, particularly when performing overhead motions.
• Tenderness: Tenderness or discomfort when palpating the AC joint.
• Swelling: Inflammation around the AC joint, often exacerbated by activity.
• Limited Range of Motion: Difficulty raising the arm or performing tasks like lifting or reaching.

How Doctors Find the Problem? (Diagnosis and Imaging)

To diagnose AC joint issues, doctors typically perform:

• Physical Examination: Palpation of the AC joint to assess tenderness and stability.
• Imaging: X-rays are used to assess joint space narrowing and the presence of bone spurs. MRIs may be used to examine soft tissue damage, and ultrasound can be used to assess swelling or osteophytes.

Classification

AC joint conditions are generally classified by the severity of the degeneration:

• Grade I: Mild inflammation with no major structural changes.
• Grade II: Moderate degeneration with mild joint space narrowing and bone spurs.
• Grade III: Severe degeneration with significant osteophytes and joint space loss.

Other Problems That Can Feel Similar (Differential Diagnosis)

Conditions like rotator cuff tendinopathy, labral tears, or frozen shoulder can also cause shoulder pain and stiffness. Proper diagnosis is crucial to differentiate AC joint arthritis from other shoulder pathologies that might require different treatments.

Treatment Options

Non-Surgical Care:

• • Physical Therapy: Exercises to improve range of motion and strength, focusing on shoulder stability.
  • NSAIDs and Steroid Injections: Used to reduce inflammation and relieve pain.
  • Activity Modification: Avoiding overhead lifting or repetitive motions that aggravate symptoms.

Surgical Care:

• • Arthroscopic AC Joint Resection: The primary treatment for severe cases, where the damaged portion of the distal clavicle is removed using small instruments through keyhole incisions.

Recovery and What to Expect After Treatment

Post-surgery, patients are typically required to wear a sling for several days to support the shoulder. After initial healing, physical therapy is essential to restore strength, flexibility, and function. Most patients experience significant pain relief and regain shoulder function within 3–6 months.

Possible Risks or Side Effects (Complications)

While rare, complications may include:

• Infection: Potential risk at the incision site.
• Persistent Pain: In some cases, patients may continue to experience discomfort after surgery.
• Recurrent Shoulder Instability: If the joint doesn’t heal properly, further surgical intervention may be necessary.

Long-Term Outlook (Prognosis)

For most patients, arthroscopic AC joint resection provides lasting pain relief, restores shoulder function, and allows a return to normal activities. Long-term outcomes are generally excellent, with minimal risk of recurrence.

Out-of-Pocket Cost

Medicare

CPT Code 29824 – Arthroscopic AC Joint Resection (Acromioclavicular Joint Debridement and Excision): $161.54

Medicare Part B typically covers 80% of the approved cost for this procedure once your annual deductible has been met, leaving you responsible for the remaining 20%. Supplemental Insurance plans such as Medigap, AARP, or Blue Cross Blue Shield generally cover that remaining 20%, minimizing or eliminating out-of-pocket expenses for Medicare-approved surgeries. These plans coordinate with Medicare to fill the coverage gap and reduce financial responsibility.

If you have Secondary Insurance, such as TRICARE, an Employer-Based Plan, or Veterans Health Administration coverage, it acts as a secondary payer. These plans usually cover any remaining coinsurance or small deductibles, which typically range from $100 to $300, depending on your plan and provider network.

Workers’ Compensation

If your arthroscopic AC joint resection is required due to a work-related injury or condition, Workers’ Compensation will cover all associated medical expenses, including surgery, rehabilitation, and follow-up care. You will not have any out-of-pocket expenses, as the employer’s insurance carrier pays all approved treatments directly.

No-Fault Insurance

If your AC joint surgery is needed due to an automobile accident, No-Fault Insurance will typically cover the full cost of your treatment, including surgery and postoperative care. The only potential out-of-pocket cost may be a small deductible or co-payment depending on your policy.

Example

Rachel Adams required arthroscopic AC joint resection (CPT 29824) to treat chronic AC joint arthritis. Her estimated Medicare out-of-pocket cost was $161.54. Since Rachel had supplemental insurance through AARP Medigap, her remaining balance was fully covered, leaving her with no out-of-pocket expenses for the procedure.

Frequently Asked Questions (FAQ)

Q. What is the acromioclavicular (AC) joint and why is it important?

A. The AC joint is where the clavicle (collarbone) meets the acromion (part of the shoulder blade). It plays a critical role in shoulder mobility and function.

Q. What causes AC joint pain or arthritis?

A. AC joint pain or arthritis can result from trauma, overuse, or degeneration, leading to discomfort during everyday tasks or sports activities.

Q. When is AC joint resection surgery recommended?

A. Surgery is typically recommended when patients experience persistent AC joint pain, discomfort with overhead motion, weightlifting, or cross-body movements, tenderness over the joint, and failure to respond to over six months of conservative care.

Q. What is arthroscopic AC joint resection?

A. Arthroscopic AC joint resection is a minimally invasive procedure that removes the damaged portion of the distal clavicle using small instruments inserted through keyhole incisions.

Q. How does arthroscopic resection differ from open surgery?

A. Unlike open surgery, arthroscopic resection preserves key stabilizing structures like the deltoid-trapezoid fascia and superior AC ligament, reducing the risk of postoperative weakness.

Q. What are the steps involved in the arthroscopic AC joint resection procedure?

A. The procedure involves patient positioning, portal creation and visualization, joint identification and debridement, bone resection of approximately 10–15 mm of the distal clavicle, and a final check to ensure no bone contact remains during shoulder motion.

Q. What imaging techniques are used before surgery?

A. Imaging may include X-rays to assess joint space narrowing or osteophytes, MRI to detect joint fluid or bone marrow edema, bone scans showing increased uptake in symptomatic joints, and ultrasound to evaluate capsule swelling or osteophytes.

Q. How is the source of shoulder pain confirmed before surgery?

A. Diagnostic injections into the AC joint can confirm the pain origin and help distinguish AC pathology from subacromial impingement.

Q. What are the expected outcomes after arthroscopic AC joint resection?

A. Patients can expect significant pain reduction, increased shoulder motion, and improved function during daily tasks.

Q. What are the advantages of arthroscopic AC joint resection over open surgery?

A. Arthroscopic resection offers less tissue disruption, faster recovery, and preservation of important stabilizing structures compared to the traditional open Mumford procedure.

Summary and Takeaway

Arthroscopic AC joint resection is an effective and minimally invasive surgical procedure that provides significant pain relief and restores shoulder function in patients with AC joint arthritis. Compared to traditional open surgery, it offers smaller incisions, faster recovery, and fewer complications. Most patients experience significant improvements in their quality of life and are able to return to normal activities within a few months.

Clinical Insight & Recent Findings

A recent study explored the clinical outcomes of arthroscopic acromioclavicular (AC) joint resection, a minimally invasive procedure designed to treat pain and dysfunction caused by arthritis or trauma at the AC joint. The study demonstrated that arthroscopic resection is associated with significant pain reduction, improved shoulder mobility, and better functional recovery, comparable to open surgery but with fewer complications and faster rehabilitation. The procedure involves small incisions through which a camera and surgical instruments are used to remove damaged bone and cartilage, preserving stabilizing structures like the deltoid-trapezoid fascia. Patients typically experience less postoperative weakness and a quicker return to normal activities, with most regaining full function within 3–6 months. Arthroscopic AC joint resection, when indicated after conservative treatments fail, offers an effective and reliable solution for patients suffering from chronic AC joint pain. (“Study on AC joint resection – see PubMed.”)

Who Performs This Treatment? (Specialists and Team Involved)

Orthopedic surgeons specializing in shoulder and upper extremity surgery typically perform arthroscopic AC joint resections. Rehabilitation specialists may also be involved in post-operative care and physical therapy.

When to See a Specialist?

You should consult a specialist if you experience persistent shoulder pain, especially when lifting, reaching overhead, or performing cross-body movements, and conservative treatments have not provided relief.

When to Go to the Emergency Room?

Seek emergency care if you experience severe shoulder pain, sudden immobility, or signs of infection (fever, redness, swelling) following surgery.

What Recovery Really Looks Like?

Recovery involves several weeks of rest, followed by physical therapy to restore strength and mobility. Most patients resume daily activities within 3–6 months, depending on the type of surgery and rehabilitation adherence.

What Happens If You Ignore It?

Ignoring AC joint arthritis or injuries can lead to persistent pain, limited shoulder motion, and further degeneration of the joint. Early surgical intervention can prevent worsening symptoms and improve long-term outcomes.

How to Prevent It?

Prevent AC joint arthritis by avoiding repetitive overhead motions, using proper lifting techniques, and maintaining shoulder strength through regular exercise.

Nutrition and Bone or Joint Health

A diet rich in calcium and vitamin D is important for bone health and may help prevent degenerative joint conditions.

Activity and Lifestyle Modifications

Post-surgery, low-impact exercises are recommended for maintaining fitness while allowing the shoulder to heal. Avoid heavy lifting and overhead activities until cleared by your surgeon.