The acromioclavicular (AC) joint is a small but complex structure connecting the collarbone (clavicle) to the highest part of the shoulder blade (acromion). Injuries typically involve either a separation, where the ligaments supporting the joint are torn, or chronic arthritis resulting from wear and tear or prior trauma. The decision to pursue surgery is highly individualized, depending on the injury’s severity, the patient’s lifestyle, and their specific functional demands. Understanding the alternatives and the commitment involved in recovery is fundamental to determining if AC joint surgery is the right choice.
Non-Surgical Treatment Options
For the majority of AC joint injuries, particularly low-grade separations, initial treatment focuses on conservative management. This approach aims to reduce pain and inflammation while allowing damaged ligaments to heal. Immediate treatment typically involves rest, applying ice, and using nonsteroidal anti-inflammatory drugs (NSAIDs) to manage discomfort.
Immobilization with a sling is often recommended for a short period, usually lasting one to four weeks for milder injuries, to protect the shoulder. Once acute pain subsides, the focus shifts quickly to restoring shoulder function through physical therapy. Therapy begins with gentle, passive, and active-assisted range of motion exercises to prevent stiffness. For most individuals with less severe AC joint injuries, this non-surgical pathway leads to a full recovery and return to activity within six to twelve weeks.
Determining the Need for Surgery
The criteria for recommending AC joint surgery are specific, generally reserved for the most unstable injuries or cases that have failed non-operative treatment. Surgery is almost always indicated for high-grade separations (Rockwood Grades IV, V, and VI), which involve severe displacement of the clavicle. These severe injuries require reconstruction to restore anatomical alignment and function.
For Grade III separations, which involve a complete ligament tear but less severe displacement, the decision is more controversial and often begins with a trial of conservative care. However, surgery may be considered initially for young, high-demand individuals, such as overhead athletes or heavy laborers, who require maximum shoulder strength and stability. Surgery is also recommended for patients experiencing chronic pain, persistent instability, or muscle fatigue after failing at least 6 to 12 weeks of non-operative treatment. Chronic AC joint arthritis that causes debilitating pain and does not respond to injections or physical therapy is an indication for surgery.
Surgical Techniques for AC Joint Repair
Surgical procedures for the AC joint are broadly categorized based on whether the primary goal is to treat arthritis or to reconstruct torn ligaments. For chronic AC joint arthritis or persistent pain, the Distal Clavicle Excision (DCE), also known as the Mumford procedure, is commonly performed. This procedure involves removing a small piece of the end of the clavicle, creating a space that prevents bone-on-bone rubbing and relieves pain.
For acute, high-grade separations, the goal is anatomical reconstruction. Modern techniques focus on reconstructing the coracoclavicular (CC) ligaments. This is often achieved using strong, synthetic fixation materials, such as suture loops or buttons (e.g., TightRope), or by using tendon grafts to recreate the torn ligaments. These complex procedures can be performed either through a traditional open incision or using minimally invasive arthroscopic techniques.
Post-Operative Recovery and Rehabilitation
Recovery follows a structured, multi-phase rehabilitation protocol. Immediately following surgery, the arm is typically immobilized in a sling for four to six weeks to allow the repaired ligaments to heal. During this initial phase, the patient performs gentle hand, wrist, and elbow exercises, along with passive and assisted range of motion (ROM) exercises for the shoulder.
The second phase, beginning around six weeks, focuses on restoring full range of motion, transitioning from passive to active movement. The strengthening phase starts around 9 to 12 weeks post-surgery, introducing resistance exercises to rebuild the strength of the rotator cuff and surrounding shoulder muscles. Advanced strengthening and functional training follow, spanning three to six months. A full return to demanding activities, such as contact sports or heavy manual labor, usually requires four to nine months, depending on the injury severity and surgical technique used.
Long-Term Outcomes and Risk Assessment
The long-term outcomes of AC joint surgery are generally favorable, with a high percentage of patients achieving a functional and stable shoulder. Between 85% and 95% of patients successfully regain adequate function and return to their prior activities, including competitive sports. A successful outcome does not always equate to 100% pain relief, and some individuals may still experience occasional discomfort.
Surgical intervention carries a risk of complications, sometimes reported as high as 27% to 44%. Common risks include hardware-related issues, such as the need for a second surgery to remove screws or plates, or the failure of synthetic implants. Other potential complications include:
- Stiffness
- Infection
- Recurrent instability due to partial loss of reduction
- Bony problems like osteolysis or clavicle fracture
For high-demand patients with severe injuries, the potential for regaining a near-normal, stable joint often justifies the surgical commitment and inherent risks.