Approach to the Acromioclavicular Joint

What it exposes. This approach gives direct access to the acromioclavicular (AC) joint, the distal clavicle and acromion, the coracoclavicular (CC) ligaments (conoid and trapezoid), and the coracoid base. It is the workhorse exposure for AC joint reconstruction (acute or chronic), distal clavicle excision (Mumford), CC ligament reconstruction or augmentation, and AC joint fixation. Incision variants. The superior strap incision is most common — centered over the AC joint and distal clavicle. An alternative saber incision runs obliquely from the posterior distal clavicle toward the coracoid and suits distal clavicle excision. An arthroscopic portal-based approach is reserved for selected low-grade or diagnostic cases. Position & landmarks. The patient is placed in the beach-chair or modified supine position with the head elevated 30 to 45 degrees. A small bump under the ipsilateral scapula protracts the shoulder and improves access to the AC joint and coracoid. The arm is draped free to allow intraoperative stress testing and reduction manoeuvres — avoid excessive traction, which stretches the brachial plexus. Intraoperative fluoroscopy (mini C-arm) is positioned for AP, axillary and Zanca views. The field extends from the sternoclavicular joint medially to the deltoid insertion laterally and includes the coracoid. A sterile tourniquet is rarely used. Palpable landmarks are the AC joint (a step-off or point of tenderness), the subcutaneous distal clavicle, the coracoid (approximately 2 cm inferior to the clavicle), the acromion, and — in thin patients — the supraclavicular nerve branches crossing the clavicle. Coracoclavicular ligament anatomy to plan around. The conoid ligament attaches to the conoid tubercle on the posterior clavicle approximately 4.5 cm medial to the AC joint (more posterior and medial); the trapezoid ligament attaches more laterally and anteriorly. Both share a common attachment at the coracoid base. Knowing these distinct footprints is essential for anatomic CC reconstruction.

Work from the skin down through the deltotrapezial fascia, opening the AC capsule and then sweeping medially along the clavicle to expose the coracoclavicular ligaments and coracoid base.

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Structures at risk, by layer

Extensile options. Extend medially along the clavicle for more proximal clavicle exposure or further CC ligament work. Extend laterally over the acromion or into the deltopectoral interval for combined procedures such as rotator cuff repair or shoulder arthroplasty. Inferior extension toward the coracoid is limited and demands protection of the lateral cord and musculocutaneous nerve. Closure. Layered closure is essential. Repair the AC capsule with absorbable suture. Close the deltotrapezial fascia with strong interrupted sutures — reinforced with suture anchors if tissue quality is poor. Approximate subcutaneous tissue and close skin; apply a sling postoperatively.

• AC joint reconstruction (acute or chronic) — CC ligament reconstruction with autograft, allograft or synthetic device, plus AC capsule repair.
• Distal clavicle excision (Mumford) — resection of 8 to 10 mm of distal clavicle with smoothing of the cut surface.
• AC joint fixation (hook plate) — plate applied with reduction maintained; removal planned at 3 to 6 months to prevent acromial erosion.
• CC ligament reconstruction or augmentation, and exposure of the scaphotrapezial-type pantrapezial work is done through other approaches; this exposure is dedicated to the AC/CC complex.