The acromioclavicular (AC) joint is the connection between the collarbone (clavicle) and the highest point of the shoulder blade (acromion). Injuries to this joint are common, especially among young active individuals, typically caused by a direct blow to the shoulder—such as falling onto the shoulder or being hit in contact sports.
AC joint injuries are categorized by severity:
- Type I and II injuries are mild and often heal without surgery.
- Types IV through VI are severe and typically require surgical repair.
- Type III injuries fall in the middle and can be treated surgically or non-surgically depending on patient activity level and symptom severity.
When Surgery Is Needed
Surgery is usually reserved for more serious AC joint injuries, or when chronic dislocation causes ongoing pain, loss of shoulder function, or visible deformity. In chronic cases where the injury is older than a few weeks, tissue healing may be limited, and biologic support—like using tendon grafts—can help restore joint stability.
What Is Open AC Joint Reconstruction?
This surgical procedure involves rebuilding the damaged ligaments around the AC joint to restore normal alignment and function. In this technique, a semitendinosus allograft (a donor tendon) is used alongside a special FiberTape cerclage system to secure the bones back into position and reinforce the reconstruction.
This method avoids using metal plates or screws that require later removal, and it reduces the risk of complications like fractures around the hardware.
Step-by-Step Surgical Procedure
1. Patient Positioning and Preparation
The patient is placed in a beach chair position—reclined and sitting slightly upright. After anesthesia, the surgical team confirms the separation using live X-rays and sterilizes the area.
2. Graft Preparation
A semitendinosus tendon (from a donor) is prepared. Its ends are stitched and tensioned to remove slack, ensuring it will hold its shape once implanted.
3. Surgical Incision and Exposure
A small incision is made near the AC joint. The skin, tissue, and muscle layers are gently separated to expose the damaged joint and surrounding structures. Any scar tissue is removed, and if necessary, a small part of the end of the collarbone is trimmed to help reposition it better.
4. Identifying the Coracoid
The coracoid process—a small bony hook under the collarbone—is carefully exposed using blunt instruments. A tunnel is created underneath this bone to allow passage of the FiberTape and graft without drilling into it (avoiding fracture risk).
5. Creating Bone Tunnels in the Clavicle
Two small tunnels are drilled in the collarbone:
- One is located slightly back and toward the midline (posteromedial).
- The second is placed more forward (anterolateral).
These serve as entry and exit points for the graft to pass through and anchor securely.
6. Graft and Suture Placement
- The FiberTape is passed under the coracoid and through one of the collarbone tunnels.
- The tendon graft is threaded through both tunnels in a crisscross pattern, which mimics the natural ligament structure and enhances stability.
7. Reducing and Securing the Joint
With the clavicle now in its correct position, the FiberTape is tightened using a specialized tensioning device that precisely adjusts the pressure (30-40 pounds). This helps restore alignment while minimizing the chance of over-tightening or stretching.
Once the joint is properly aligned, permanent knots are tied to secure the FiberTape in place.
8. Final Graft Fixation
The ends of the graft are anchored inside the bone tunnels using PEEK tenodesis screws, which are strong and biocompatible. After this, any remaining graft is laid over the top of the AC joint and stitched down to reinforce the capsule and further stabilize the joint.
Final X-rays are taken to confirm everything is correctly positioned.
Benefits of This Technique
- Anatomic Reconstruction: Mimics the body’s original ligament structure.
- Avoids Drilling Into Coracoid: Reduces risk of fracture by looping under rather than through the coracoid.
- Strong Initial Fixation: The tensioning system offers controlled and secure alignment.
- Biologic Augmentation: The tendon graft helps long-term healing and integration.
Risks and Considerations
As with any surgery, there are potential risks:
- Fracture of the clavicle
- Neurovascular injury
- Recurrence of the shoulder deformity
- Allergic reaction to donor tissue (if allograft is used)
These complications are uncommon, and the surgical technique has been designed to reduce them where possible—for example, by avoiding hardware that could migrate or break.
What to Expect After Surgery
Patients can expect:
- Immobilization in a sling for a few weeks
- Physical therapy to restore range of motion and strength
- Gradual return to normal activities and sports over several months
Most patients experience significant pain relief, improved shoulder function, and cosmetic correction of the deformity.
Summary
Open AC joint reconstruction using a semitendinosus allograft and FiberTape cerclage system is a safe and effective option for chronic AC joint injuries. It offers strong, natural-looking results with reduced risk of complications compared to older methods involving plates or screws.
This technique is particularly well-suited for patients with long-standing shoulder separations who want to return to active lifestyles with a stable, functional shoulder.
If you’re suffering from a persistent AC joint injury, speak with your orthopedic surgeon about whether this approach is right for you.
Do you have more questions?
Q. What is an open acromioclavicular (AC) joint reconstruction?
A. It is a surgical procedure to repair and stabilize the AC joint, which connects the collarbone (clavicle) to the shoulder blade (acromion), typically after injury or dislocation.
Q. Why might someone need an AC joint reconstruction?
A. This surgery is usually needed after severe AC joint injuries or dislocations that cause pain, instability, or functional limitations.
Q. What causes AC joint injuries?
A. AC joint injuries often result from a direct blow to the shoulder, falls onto the shoulder, or traumatic events during sports or accidents.
Q. What symptoms indicate an AC joint injury?
A. Symptoms include shoulder pain, swelling, tenderness over the AC joint, a visible bump or deformity, and decreased shoulder function.
Q. How is the AC joint reconstruction surgery performed?
A. The surgeon makes an incision over the AC joint, repairs or reconstructs the damaged ligaments, and stabilizes the joint using sutures, grafts, or implants.
Q. What types of grafts might be used in AC joint reconstruction?
A. Grafts can be taken from the patient’s own tissue (autograft) or from a donor (allograft) to reconstruct the ligaments.
Q. What is the goal of the surgery?
A. The goal is to restore joint stability, relieve pain, and improve shoulder function.
Q. How long does the surgery typically take?
A. The procedure usually takes about one to two hours, depending on the complexity.
Q. What is the recovery process after AC joint reconstruction?
A. Recovery involves immobilization in a sling, followed by physical therapy to regain motion and strength over several months.
Q. When can patients expect to return to normal activities?
A. Most patients can return to daily activities within a few weeks, but full recovery and return to sports or heavy lifting may take several months.
Q. Are there risks or complications associated with the surgery?
A. Potential risks include infection, nerve injury, stiffness, hardware irritation, and failure of the reconstruction.
Q. How successful is AC joint reconstruction surgery?
A. Most patients experience significant pain relief and improved shoulder stability and function after surgery.
Q. Is physical therapy necessary after surgery?
A. Yes, physical therapy is essential to restore motion, strength, and function of the shoulder.
Q. What types of injuries are classified as severe enough to require surgery?
A. Severe AC joint separations such as Rockwood types IV, V, and VI typically require surgical reconstruction.
Q. Can the surgery be performed arthroscopically?
A. This page focuses on open reconstruction; however, some cases may be treated arthroscopically depending on surgeon preference and injury type.
Q. What is the expected scar from surgery?
A. The scar is located over the AC joint and usually fades over time but will be permanent.
Q. Is pain management addressed after surgery?
A. Yes, pain management includes medications and careful monitoring during recovery to ensure patient comfort.
Q. What should patients do to prepare for AC joint reconstruction?
A. Patients should discuss their medical history, medications, and expectations with their surgeon and follow preoperative instructions closely.
Q. How is joint stability assessed after surgery?
A. Stability is evaluated during follow-up visits through physical examination and imaging if necessary.
Q. What kind of activities should be avoided immediately after surgery?
A. Patients should avoid lifting heavy objects, overhead activities, and any motion that stresses the AC joint until cleared by their surgeon.
Q. What follow-up care is required after surgery?
A. Follow-up includes wound checks, physical therapy progression, and monitoring for complications.
