AC Joint: Understanding Resection Surgery, Recovery, and Outcomes

Can you remove the AC joint?

While the acromioclavicular (AC) joint cannot be entirely "removed" from the body, a common surgical procedure known as distal clavicle excision or AC joint resection involves removing a small portion of the collarbone (clavicle) to alleviate pain and restore function.

Understanding the AC Joint: Anatomy and Function

The acromioclavicular (AC) joint is a critical articulation in the shoulder complex, connecting the acromion (a bony projection of the shoulder blade, or scapula) to the distal end of the clavicle (collarbone). This joint is stabilized by several ligaments: the acromioclavicular ligaments, which surround the joint capsule, and the powerful coracoclavicular ligaments (conoid and trapezoid), which connect the clavicle to the coracoid process of the scapula.

Key Functions of the AC Joint:

• Scapular Mobility: It allows for subtle gliding and rotation of the scapula on the clavicle, crucial for full range of motion of the arm, particularly during overhead activities.
• Force Transmission: The AC joint plays a vital role in transmitting forces from the arm to the axial skeleton.
• Shoulder Stability: While small, it contributes significantly to the overall stability of the shoulder girdle.

Why Might the AC Joint "Need Removal"?

The term "removal" in this context refers to a surgical intervention designed to address specific painful conditions of the AC joint. The primary goal of such a procedure is typically to create more space within the joint, preventing bone-on-bone friction and relieving pain. Common reasons for considering this surgery include:

• Osteoarthritis: Degenerative changes or "wear and tear" of the articular cartilage within the joint, often leading to pain, stiffness, and crepitus (grinding sensation). This can be primary (age-related) or secondary (post-traumatic, following an AC joint injury).
• Distal Clavicle Osteolysis (DCO): Also known as "weightlifter's shoulder," this condition involves the breakdown and resorption of bone at the end of the clavicle due to repetitive microtrauma and stress, common in athletes involved in overhead activities or heavy lifting.
• AC Joint Impingement: Similar to shoulder impingement, this occurs when soft tissues or bone spurs within the AC joint are compressed, causing pain, especially during arm elevation or horizontal adduction (reaching across the body).
• Failed Conservative Treatment: Surgery is typically considered only after a prolonged period of conservative management (rest, ice, anti-inflammatory medications, physical therapy, corticosteroid injections) has failed to provide adequate pain relief and functional improvement.

Surgical Interventions: AC Joint Resection (Distal Clavicle Excision)

The surgical procedure to address the painful AC joint is formally known as distal clavicle excision or AC joint resection. This involves removing a small segment (typically 5-10 millimeters) of the outer end of the clavicle. The intent is not to remove the entire joint but to create a gap between the clavicle and the acromion, eliminating the source of impingement or arthritic pain.

Techniques for Distal Clavicle Excision:

• Arthroscopic Distal Clavicle Excision: This minimally invasive approach involves small incisions and the use of an arthroscope (a small camera) and specialized instruments. It generally results in less post-operative pain, smaller scars, and potentially faster recovery.
• Open Distal Clavicle Excision: This traditional method involves a larger incision over the top of the shoulder to directly access the joint. While more invasive, it may be preferred in cases of significant deformity or when other procedures are simultaneously performed.

The choice of technique depends on the surgeon's preference, the patient's specific condition, and any co-existing shoulder pathologies.

The Surgical Procedure: What to Expect

Distal clavicle excision is typically performed as an outpatient procedure under general anesthesia, sometimes with a regional nerve block for extended pain relief.

• Arthroscopic Approach: The surgeon makes a few small incisions (portals) around the shoulder. The arthroscope is inserted into one portal, allowing visualization of the joint on a monitor. Specialized burrs or shavers are then inserted through other portals to precisely remove the desired portion of the distal clavicle.
• Open Approach: A single incision, usually a few centimeters long, is made over the AC joint. The muscles are carefully retracted, and the end of the clavicle is resected using a small saw or osteotome.

After the bone is removed, the incisions are closed with sutures or surgical tape.

Recovery and Rehabilitation

Recovery from AC joint resection is a critical phase that significantly impacts the long-term outcome. A structured rehabilitation program is essential.

• Initial Phase (Weeks 0-2): Pain management, arm sling for comfort and protection, gentle passive and active-assisted range of motion exercises to prevent stiffness.
• Intermediate Phase (Weeks 2-6): Progressive increase in active range of motion, initiation of light strengthening exercises for the rotator cuff and scapular stabilizers, with a focus on restoring normal movement patterns.
• Advanced Phase (Weeks 6-12+): Gradual progression to more aggressive strengthening, including resistance exercises and functional movements. Sport-specific or activity-specific drills are introduced, with a focus on power, endurance, and return to full activity.

Full recovery can take anywhere from 3 to 6 months, depending on the individual, the surgical technique, and adherence to the rehabilitation protocol. Patients are typically advised to avoid heavy overhead lifting or contact sports until cleared by their surgeon and physical therapist.

Potential Risks and Long-Term Outcomes

As with any surgical procedure, AC joint resection carries potential risks, including:

• Infection: Though rare, it's a possibility with any incision.
• Stiffness or Limited Range of Motion: Inadequate rehabilitation can lead to persistent stiffness.
• Persistent Pain: While the goal is pain relief, some patients may experience residual discomfort.
• Nerve or Blood Vessel Damage: Rare, but possible during the procedure.
• Cosmetic Issues: Scarring at the incision site.
• Failure of Procedure: In some cases, symptoms may not fully resolve, or new issues may arise.

Despite these risks, the long-term outcomes of distal clavicle excision are generally favorable, with a high success rate in relieving pain and improving function, particularly for patients suffering from AC joint osteoarthritis or osteolysis. Most individuals can return to their previous activity levels, including sports and heavy lifting, once fully recovered and rehabilitated.

Prevention of AC Joint Injuries

While some AC joint issues are degenerative, others can be prevented or mitigated through proper training and awareness:

• Proper Lifting Mechanics: Ensure correct form during exercises like bench press, overhead press, and dips to minimize stress on the AC joint. Avoid excessive depth or range of motion that places undue strain on the joint.
• Scapular Stability: Strengthen the muscles that stabilize the scapula (e.g., serratus anterior, rhomboids, trapezius). A stable scapula provides a better foundation for the clavicle.
• Rotator Cuff Strength: Maintain strong and balanced rotator cuff muscles to ensure optimal shoulder joint mechanics.
• Progressive Overload: Increase training intensity, volume, and weight gradually to allow the joint and surrounding tissues to adapt.
• Listen to Your Body: Pay attention to pain signals. Persistent AC joint pain, especially during or after exercise, warrants professional evaluation.
• Avoid Direct Trauma: Protect the shoulder during contact sports or activities with a high risk of falls.

Conclusion

The question "Can you remove the AC joint?" is best understood as inquiring about a specific surgical intervention: distal clavicle excision. This procedure involves the precise removal of a small portion of the clavicle to alleviate chronic pain and dysfunction primarily caused by osteoarthritis, osteolysis, or impingement. It is a well-established and generally successful surgery, typically considered after conservative treatments have failed. For anyone experiencing persistent AC joint pain, consultation with an orthopedic surgeon is crucial to determine the underlying cause and the most appropriate course of action, which may or may not involve surgical intervention.