71 Open Acromioclavicular Joint Reconstruction

10.1055/b-0039-167720

71 Open Acromioclavicular Joint Reconstruction

Neil S. Kumar and Augustus D. Mazzocca

Abstract

This chapter reviews the operative technique for open anatomic coracoclavicular ligament reconstruction (ACCR). The procedure aims to reestablish the natural biomechanics of the shoulder and alleviate pain. Indications for reconstruction following acromioclavicular (AC) joint disruption include persistent pain or distal clavicle instability after 3 to 4 weeks of nonoperative treatment. Preoperative bilateral Zanca views and axillary lateral radiographs identify injury pattern and concomitant pathology. Reconstruction focuses on restoring natural anatomical relationships. Trapezoid and conoid tunnels are placed 25 and 45 mm medial to the AC joint, respectively, to re-create the native anatomy and avoid the inferior bone density of the lateral clavicle. A third tunnel is placed 10 mm medial to the joint and paired with an acromial tunnel for a figure-of-8 suture fixation. Peroneus longus allograft is combined with a high-strength nonabsorbable suture for biologic and nonbiologic fixation. Reduction is achieved with scapular elevation and an anteriorly directed force on the distal clavicle. Tenodesis screws and suture technique create internal biologic and nonbiologic braces. The deltotrapezial fascia is critical to sagittal stability of the distal clavicle and must be repaired anatomically. Strengthening is started at 12 weeks postoperatively with return to collision sports at 6 months.

71.1 Goals of Procedure

Open anatomic coracoclavicular ligament reconstruction (ACCR) aims to reestablish the natural biomechanics of the shoulder and alleviate pain. The goals of surgery are to restore shoulder range of motion (ROM) and strength, allowing the patient to return to full activities.

71.2 Advantages

Restoration of normal acromioclavicular (AC) joint anatomy plays a vital role in achieving stability of the distal clavicle. Open surgery provides direct visualization of the AC joint and distal clavicle, helping the surgeon achieve the goal of anatomic reconstruction. Acromial and clavicular tunnel locations can be directly measured from the AC joint and related to key bony landmarks, allowing for accurate tunnel placement. High-grade dislocations may disrupt the fascia and cause the distal clavicle to “buttonhole” through the tissue, preventing reduction. Open visualization allows the surgeon to release the clavicle and repair traumatic fascial tears, which is essential to maintain anteroposterior stability of the distal clavicle.

71.3 Indications

In the treatment algorithm of the senior author, the major indication for open ACCR is increasing or persistent shoulder pain, particularly with subjective distal clavicle instability, which limits the patient from participation in activities after 3 to 4 weeks of nonoperative treatment. Tented skin “at risk” secondary to significant distal clavicle deformity also warrants surgical intervention.

Type I and II injuries are typically lower energy ¹ and are treated nonoperatively with pain relief modalities, early shoulder motion, and periscapular and shoulder strengthening for 6 to 12 weeks. These injuries inherently maintain some degree of ligamentous stability of the distal clavicle and, therefore, are surgically treated with distal clavicle excision. However, surgery is indicated only if chronic pain and dysfunction develop, which in our clinical experience is rare.

The evidence regarding treatment for type III injuries is still inconclusive. ² In the practice of the senior author, these patients complete 3 to 4 weeks of nonoperative treatment to reduce pain, improve ROM, and increase use of the injured upper extremity. If significant improvements are made, rehabilitation is completed; patients who do not show marked progress undergo surgical reconstruction. It is important to note that many variables are examined when choosing the length of nonsurgical treatment, particularly for athletes or heavy laborers. Type of labor or sport, especially those involving contact or overhead activity, must be considered. Other factors such as competition level, years of eligibility remaining, and whether injury occurred in- or offseason are also reviewed.

High-energy type IV, V, and VI dislocations are treated operatively. Such injuries frequently involve trauma to the deltotrapezial fascia and may lead to “buttonholing” of the distal clavicle, requiring surgical reduction. ¹ Nonsurgical treatment risks the morbidity of persistent pain, restricted ROM, and shoulder girdle weakness. ³

71.4 Contraindications

Contraindications to ACCR include nerve injury to the ipsilateral upper extremity limiting shoulder function or ongoing chronic infection. Relative contraindications include significant distal clavicle bone loss, displaced coracoid fracture, and poor skin quality overlying the AC joint.

71.5 Preoperative Preparation/Positioning

71.5.1 Imaging

A standing bilateral Zanca view radiograph with the arms by the side is performed to allow side-to-side comparison of the coracoclavicular (CC) distance. A cross-body adduction view may show the distal clavicle overriding the acromion, indicating AC joint instability. An axillary lateral X-ray determines distal clavicle sagittal position. Shoulder radiographs can reveal additional trauma, such as coracoid or glenoid fractures.

MRI can be obtained if concerns exist for concomitant soft-tissue injuries. In younger patients, biceps or superior labral anterior and posterior (SLAP) tears should be suspected; rotator cuff tears occur more often in older patients. CT scan can confirm suspected coracoid fracture.

71.5.2 Positioning

Following intubation, the patient is placed in the beach-chair position. The head is slightly rotated away from the surgical site to allow for conoid tunnel drilling. The hips are flexed to 60 to 70 degrees and a pillow is placed under the knees. Sequential compression devices are used on both lower extremities. The patient is positioned as far laterally on the table as possible and the torso is elevated with a bump placed under the medial border of the scapula. The patient is secured to the table with tape across the torso and with a safety belt across the thighs. The scapular bump is also secured with tape to prevent loss of positioning when manipulating the upper extremity.

The mini C arm is used to obtain a Zanca view of the operative shoulder and a reduction maneuver, typically scapular elevation with anterior translation of the clavicle, is fluoroscopically reviewed to visualize joint reduction. The operative field is prepped to include the sternoclavicular joint medially and the scapular spine posteriorly.

71.6 Operative Technique

71.6.1 Surgical Approach

The coracoid, acromion, AC joint, and lateral one-half of the clavicle are marked ( Fig. 71.1 ). We utilize a curved incision along Langer lines approximately 30 mm medial to the AC joint. The incision extends 20 mm posterior to the posterior border of the clavicle and to the anterior tip of the coracoid process. This incision allows access anteriorly to the coracoid, medially to the conoid tubercle, and laterally to the lateral border of the acromion. Extending the incision posteriorly toward the scapular spine can improve exposure of the distal clavicle and AC joint.

**Fig. 71.1** The incision extends 20 mm posterior to the posterior border of the clavicle and to the anterior tip of the coracoid process.

The skin is sharply incised and needle-tip electrocautery is used to complete the dissection to the level of the deltotrapezial fascia. Self-retaining retractors aid dissection and maintain strict hemostasis. Skin flaps superficial to the fascial layer are raised medially and laterally to improve exposure. Flaps should be kept as thick as possible to avoid postoperative wound complications. A full-thickness fascial incision in line with the clavicle is made on the superior clavicular surface between the trapezius insertion posteriorly and deltoid origin anteriorly (Video 71.1). The fascial incision continues over the acromion posterior to the posterior border of the clavicle. It is critical to extend the fascial cut a few millimeters lateral to the AC joint and to the conoid tubercle medially in order to place anatomic drill holes; we typically ensure access up to 5 cm medial to the AC joint. The anterior clavicle is skeletonized to create a full-thickness periosteal flap including the deltoid origin. Of note, the deltoid has a second origin that lies on the deep and inferior surface of the clavicle, which must be dissected subperiosteally as well. Once both deltoid layers are dissected, a tagging suture is placed. The trapezius insertion is skeletonized with subperiosteal dissection off the posterior clavicular border and a tagging suture is placed. At this time, a provisional reduction maneuver is performed with an anteriorly directed force on the distal clavicle with scapular elevation. Direct and fluoroscopic visualization can verify anatomic joint reduction and identify interfering soft tissue.

Blunt dissection is used at this point to determine the medial and lateral borders of the coracoid process. Needle-tip electrocautery is used to peel the soft tissues off of the superior surface ( Fig. 71.2 ). Here, extreme care must be taken to keep the dissection on the bony coracoid surface to avoid injuring surrounding neurovascular structures, such as the lateral cord, musculocutaneous nerve, and axillary artery. Once the coracoid can be visualized to the anterior tip, blunt dissection of the medial and lateral borders creates a plane for the curved suture passer. A high-strength nonabsorbable shuttling suture is passed from medial to lateral around the anterior coracoid process. The suture typically “settles” posteriorly at the base of the coracoid; the surgeon should ensure the suture rests anteriorly toward the tip of the coracoid process to avoid injuring the suprascapular nerve during graft passage.