Surgical Technique Sport 2023, Jan, 04 | 12:00 am

Repair and Reconstruction of Acromioclavicular Injuries

Repair and Reconstruction of Acromioclavicular Injuries

 

 

 

DEFINITION

About 9% of shoulder girdle injuries involve damage to the acromioclavicular (AC) joint.16

The AC joint separation involves disruption of the AC ligaments, with varying degrees of injury to the coracoclavicular (CC) ligaments, deltoid, and trapezius muscle attachment.

The AC joint injuries are classified by the the severity of injury, radiographic findings including the position of the clavicle relative to the acromion and reducibility of the AC joint with shoulder shrugging (Table 1).

 

 

ANATOMY

 

The AC joint is a diarthrodial joint that is innervated by the lateral pectoral nerve and the suprascapular nerve.

 

The articular surfaces of the AC joint are made up of hyaline cartilage and separated by an intra-articular meniscus type of structure, all surrounded by a joint capsule with a synovial lining.

 

The AC joint primarily rotates as well as translates in the anteroposterior (AP) as well the superoinferior plane. Normal scapular motion consists of substantial rotations around three axes and plays a major role in the motion at the AC joint. The scapula (acromion) can protract and retract, using the AC joint as a pivot point.

 

The static stabilizers of the AC joint includes the AC ligaments (superior, inferior, anterior, and posterior) and the CC ligaments (trapezoid and conoid). The dynamic stabilizers consist of the deltoid and trapezius muscles.

 

The AC joint capsule and the capsular ligaments (mainly the superior and posterior AC capsular ligaments) are the primary restraints to anterior-to-posterior translation of distal clavicle.7

 

The coracoclavicular ligaments (trapezoid and conoid) ligaments span the CC space and contribute to vertical stability. The trapezoid attaches on the undersurface of the clavicle at an anterolateral position. The conoid is a broad stout ligament located in a posterior and medial position (conoid tubercle). Both the trapezoid and conoid are posterior to the pectoralis minor attachment on the coracoid (FIG 1).

 

The AC and CC ligaments all contribute to the prevention of motion in all planes. The conoid ligament has the highest in situ forces with superior loads, regardless of the integrity of the AC ligaments. The AC ligaments are the main restraints to posterior and anterior translation. However, when the AC ligaments are transected, the

conoid is the primary restraint to anterior loads and the trapezoid is the primary restraint to posterior loads.4

 

PATHOGENESIS

 

The mechanism of most AC joint injuries is a direct blow to the point of the shoulder (lateral acromion) with the arm adducted.

 

Indirect injury occurs by falling on an adducted outstretched hand or elbow, causing the humeral head to translocate superiorly and drive the humeral head into the acromion.

NATURAL HISTORY

 

Most patients with type I or type II AC joint separations typically have full recovery with no long-term sequelae. However, some patients continue to be symptomatic. In one study, up to 27% of patients with types I and II injuries had persistent pain and required a surgical procedure. Some patients treated nonoperatively continued

to have instability and pain with provocative tests (level IV evidence).11

 

Most patients with type III separations do well with conservative treatment. In a survey of Major League Baseball team physicians, 80% of athletes treated nonoperatively had complete pain relief and normal function (level IV

evidence).9 Studies have failed to show a statistical difference in the return to activity (level IV evidence).12

 

Types IV, V, and VI AC joint separations do poorly without operative intervention (level V evidence).2 Persistent pain and functional deficit is attributed to a chronically dislocated AC joint with severe soft tissue disruption.

 

PATIENT HISTORY AND PHYSICAL FINDINGS

 

The mechanism of injury is an important history finding that clues one into a possible AC joint injury.

 

Pain in the AC joint region and obvious deformity of the AC joint are common physical presentations of AC joint separation.

 

In the absence of an obvious deformity, AC joint injury can be identified by a triad of point tenderness, positive pain at the AC joint with cross-arm adduction, and relief of symptoms by injection of a local anesthetic into the AC joint.

 

Special tests for AC joint pathology:

 

 

AC joint compression (shear) test: Isolated painful movement at the AC joint in conjunction with a history of direct trauma indicates AC joint pathology.

 

Cross-arm adduction test: Look for pain specifically at the AC joint. Pain at the posterior aspect of shoulder or lateral shoulder might indicate other pathology.

 

Paxinos test21: In a positive Paxinos test, tenderness or pain is present/worsened in the AC joint region when the examiner applies pressure to the acromion in an anterosuperior direction and downward pressure to the midpart of the clavicular shaft.

 

 

Table 1 Classification of Acromioclavicular (AC) Joint Injuries

I

Sprain of the AC

joint with all ligaments intact Mechanism of injury consistent with AC joint injury No evidence of instability

Point tenderness

at the AC joint and positive provocative tests

Radiographs

are normal.

 

 

P.103

 

 

Type

Description

Illustration

Examination Findings

Radiographic Findings

 

 

  1. Rupture of AC ligaments Sprain of coracoclavicular (CC) ligaments

     

     

     

     

  2. Complete disruption of both the AC and CC ligaments without significant disruption of the deltoid or trapezial fascia The clavicle is unstable in both the horizontal and vertical planes.

    Mild subluxation of the AC joint can be observed with stress examination.

     

    The upper extremity is usually held in an adducted position with the acromion depressed while the clavicle appears high-riding, but in reality, the acromion and the rest of the upper extremity is displaced inferior to the horizontal plane of the lateral clavicle.

    Radiographs of the lateral end of the clavicle may be slightly elevated, but stress views fail to show a 100%

    separation of the clavicle and acromion.

     

    Radiographs show up to 100%

    increase in the CC interspace.

     

     

     

     

     

  3. Complete disruption of both the AC and CC ligaments

    The distal clavicle is posteriorly displaced into the trapezius muscle and may tent the posterior skin. Evaluation of the sternoclavicular (SC) joint is necessary to rule out anterior SC joint dislocation.

    Posteriorly displaced clavicle can be seen on axillary view, which is always obtained in the standard radiographic evaluation of the AC joint.

     

     

     

  4. AC and CC ligaments are disrupted.

    Severe droop secondary to anteroinferior

    Trapezial and deltoid fascia disrupted.

     

     

     

     

    translation of the scapula around the thorax due to the weight of the arm and the geometry of the chest wall. This is considered the third translation of the scapula with loss of the clavicular strut. Reduction of the distal clavicle with shoulder shrug differentiates type III from type V (distal clavicle buttonhole through soft tissue sleeve).

    Two to three times increase in the CC distance or a 100%-300%

    increase in the clavicleto-acromion radiographic distance.

     

  5. Inferior dislocation of distal clavicle Reduction may be blocked from interposition of the intact posterosuperior AC ligaments within the AC interval. Mechanism is thought to be severe hyperabduction and external rotation of the arm combined with retraction of the scapula

The distal clavicle is found in two orientations, either subacromial or subcoracoid, behind the intact conjoined tendon.

 

 

P.104

 

 

 

FIG 1 • A. Anterior view. The trapezoid is anterolateral, whereas the conoid is a posteromedial structure. B. Posterior view. The conoid can be seen as a broad ligament that fans out, attaching to the clavicle in a posteromedial position.

 

 

O'Brien test: Symptoms at the top of the joint must be confirmed by examiner palpating the AC joint. Anterior glenohumeral joint pain suggests labral or biceps pathology.

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

The AC joint is more superficial and surrounded by less soft tissue than the glenohumeral joint. The AC joint may be better visualized if a reduced penetration strength is used compared to standard radiographs of the glenohumeral joint.

 

Standard radiographs at authors institution include AP view, supraspinatus outlet view (FIG 2A), and axillary and Zanca views.

 

 

 

FIG 2 Positioning for radiographic studies. A. Supraspinatus outlet view. B,C. Zanca view. For optimal visualization of the AC joint, the x-ray source is directed 10 degrees cephalad with reduced penetration strength compared to a standard radiograph. D. Stryker notch view. This view helps rule out concomitant injuries. It is helpful when a coracoid fracture is suspected with a normal CC interspace.

 

 

A Zanca view is made by tilting the x-ray beam 10 to 15 degrees toward the cephalic direction (FIG 2B,C). An increase in the CC distance (usually 1.1 to 1.3 cm) of 25% to 50% over the normal side indicates complete CC ligament disruption. A normal CC interspace (average 1.1 to 1.3 cm), in conjunction with a complete dislocation of the AC joint, may indicate a coracoid fracture. This is better seen on a Stryker notch view (FIG 2D).

 

The AC joint width is normally 1 to 3 mm and decreases with age. The width seen on radiographs is influenced by the individual variability of obliquity of the joint in relation to the x-ray beam.

 

Although seldom necessary and mainly a historical practice, stress views (5 to 10 pounds placed in the ipsilateral hand) with increased CC interspace on the AP view may help differentiate between type II and type III injuries.

 

 

P.105

 

An axillary view of the shoulder is important in differentiating a type III from a type IV AC joint injury. Coracoid base fractures can also be identified on this view.

 

Bone scan may help confirm subtle AC joint pathology and arthrosis but is rarely required in clinic.

DIFFERENTIAL DIAGNOSIS

 

 

 

 

Cervical spine pathology Trapezial spasm Scapular dyskinesia Hyperlaxity

 

 

Distal clavicle or acromion fracture Coracoid fracture

 

Glenohumeral pathology (impingement, rotator cuff, Hill-Sachs, Bankart, superior labral anterior posterior [SLAP] lesion, biceps)

 

Ulnar paresthesias

 

Thoracic outlet syndrome

TREATMENT

The main goals of treatment are to achieve a pain-free shoulder with full range of motion and strength and no limitations in activities.

 

 

NONOPERATIVE MANAGEMENT

 

Most type I and type II AC joint separations are treated in a nonoperative fashion.

 

Treatment begins with a sling, ice, and a brief period of immobilization only for pain control. Rehabilitation is started as soon as tolerated.

 

The rehabilitation program consists of four phases3:

 

 

 

Pain control, immediate protective range of motion, and isometric exercises Strengthening exercises using isotonic contractions

 

Unrestricted functional participation with the goal of increasing strength, power, endurance, and neuromuscular control

 

 

Return to activity with sports-specific functional drills Type III injuries:

 

These patients are usually evaluated on a case-by-case basis, taking into account variables like hand dominance, occupation, heavy labor, position and sport requirements (quarterbacks, pitchers), scapulothoracic dysfunction, and risk for reinjury.

 

In a meta-analysis of 1172 patients, 88% of those treated with surgery and 87% of those treated without surgery had satisfactory outcomes (level IV evidence).12

 

In patients with type III injuries treated nonoperatively versus operatively, there was no difference in strength at 2 years of follow-up (level IV evidence).19

 

Schlegel et al17 found that only 20% of patients reported a suboptimal outcome with conservative care. Objective studies showed that patients had no limitation of shoulder motion in the injured extremity and no

difference compared with the unaffected extremity in rotational shoulder muscle strength. A finding that may affect heavy laborers was a decrease of 17% in bench press strength at the 1-year follow-up (level IV evidence).

 

 

Currently, there is inconclusive evidence to support for surgical treatment of type III AC joint dislocations.2,18 If symptoms persist for greater than 3 months—including increased pain, impingement due to scapular dyskinesia, decreased strength,▪ inability to get the arm into a cocking position in throwing, and painful instability, especially posterior instability with the clavicle abutting the anterior portion of the spine of the scapula— then operative intervention may be indicated. Clinical studies looking at the outcomes of patients treated for AC joint dislocation are plagued with multiple issues: most of the studies are retrospective in design; have a mixture of types III, IV, and V; have both acute and chronic dislocations in the same cohort; and are treated with multiple different techniques within the same cohort. Long-term follow-ups are not available. Furthermore, the study groups contain mixed patient population (laborers, throwers) and the outcome measures are not standardized.

 

SURGICAL MANAGEMENT

 

Complete AC joint injuries (types IV, V, and VI) are usually treated operatively because of the significant morbidity associated with persistently dislocated joint and severe soft tissue disruption.

 

For type III AC joint separation, one approach is to treat these injuries conservatively for 12 weeks and consider surgical stabilization if persistent pain and instability exist. In an alternative approach, a type III AC joint separation can be primarily treated surgically especially in an athlete and high-demand patient to allow quicker return to work or play and limit the duration of painful disability.

 

Operative interventions can be broadly divided into the following:

 

 

AC joint stabilization using hook plates, pins, or K-wires

 

CC space stabilization using suture loop, screw, Endo-Button (Smith & Nephew, Andover, MA), suture anchor, and other similar devices

 

 

Ligament reconstruction: CC ligament and/or AC ligament reconstruction using autograft or allograft Dynamic muscle transfer (proximally based conjoint tendon transfer)

 

Anatomic reconstruction of the coracoclavicular ligaments (ACCR) attempts to recreate the normal anatomy and biomechanics of the AC joint and CC space. This technique has been extensively studied in our biomechanics laboratory and is our procedure of choice and is described here. The modified CA ligament transfer (Weaver-Dunn), which is another popular technique for the reconstruction of the AC joint, is also presented here. Various arthroscopic techniques have been described for surgical repair of AC joint separations and are discussed in this book as a separate chapter.

 

Preoperative Planning

 

A successful outcome depends on reasonable patient expectations and compliance with the postoperative regimen, including strict postoperative sling immobilization for 6 weeks.

 

In the treatment of chronic AC joint pain, arthroscopy of the glenohumeral joint can be undertaken to rule out concomitant injuries. Missed SLAP lesions and labral pathology have been reported as a cause of failure to

improve after distal clavicle resection, especially in younger population with posttraumatic AC joint arthrosis.1

 

Magnetic resonance imaging (MRI) of the shoulder may be obtained to rule out concomitant injuries that also need to be addressed.

 

If using a modified Weaver-Dunn or ACCR, the surgeon should discuss with the patient the options for autograft

or allograft.

 

 

P.106

Positioning

 

 

The patient is placed in the beach-chair position after induction of general anesthesia (FIG 3). We prefer a standard table that provides posterior support and stabilization of the scapula.

 

 

A small bump is placed on the medial scapular edge to stabilize it and elevate the coracoid anteriorly. The head is mobile because repositioning is sometimes necessary during medial clavicle drilling.

 

Wide draping is done to expose the sternoclavicular joint and posterior clavicle for complete visualization of the shoulder girdle.

 

The arm is free draped to allow free motion and maneuvers to reduce the AC joint.

 

Approach

 

Osteologic analysis of the clavicle in our lab demonstrated that the mean length from the lateral end of the clavicle, or the AC joint, to the CC ligaments is 46.3 ± 5 mm; the distance between the trapezoid laterally and the conoid medially is 21.4 ± 4.2 mm.15

 

In both the Weaver-Dunn and ACCR procedures, the incision is made to allow adequate exposure of the AC joint and coracoid.

 

The incision for the Weaver-Dunn is more lateral compared to the ACCR because of the exposure necessary for CA ligament acquisition and because the ACCR clavicle preparation is performed slightly more medially.

 

 

 

FIG 3 • The beach-chair position is used, with a small bump placed on the medial scapular edge to bring the coracoid anteriorly and to secure the scapula. The head should be mobile to allow repositioning if needed during clavicle reaming. The arm is free draped from the sternoclavicular joint laterally.

 

Although the AC joint and clavicle are superficial structures with little subcutaneous tissue, in our experience, full-thickness soft tissue flaps can be elevated to improve visualization without compromising the vascularity of the skin.

 

Full-thickness flaps of the deltotrapezial fascia during the approach are critical for closure. Tagging sutures can be placed during the approach to allow for quick and effective soft tissue coverage over the repair.

 

TECHNIQUES

  • Anatomic Coracoclavicular Ligament Reconstruction (ACCR)

    Surgical Exposure

     

    Arthroscopy of the glenohumeral joint can be performed to look for concomitant injuries.

     

    A skin incision is centered 3.5 cm medial to the AC joint starting at the posterior clavicle in a curvilinear fashion toward the coracoid process along the Langer lines.

     

    The incision is sometimes placed obliquely because the key is to have full visualization of the AC joint laterally and the coracoid process medially (TECH FIG 1).

     

    Superficial skin bleeders are controlled down to the deep fascia with a needle-tip Bovie. Full-thickness cutaneous flaps are elevated to define the underlying deltotrapezial fascia attachment onto the clavicle and acromion.

     

    Full-thickness fascioperiosteal flaps are elevated from the midline of the clavicle both posteriorly and anteriorly, skeletonizing the clavicle. One can identify a raphe between the deltoid and trapezius attachments on clavicle and acromion, which serves as a good avascular plane for dissection.

     

    Tagging sutures are placed on the edges of the deltotrapezial fascia. Traction on the tagging sutures or a Gelpi retractor under the flaps is used for adequate visualization. The tagging sutures also allow for easy and precise closure of the fascia at the end of the procedure.

     

    Once the surgical approach is complete, a trial reduction is attempted. This involves upward displacement of the scapulohumeral complex combined with the use of a large, pointed▪ reduction forceps placed on the coracoid process and the clavicle to reduce the AC joint.

     

     

     

    TECH FIG 1 • A,B. A curvilinear incision is made 3.5 cm medial to the AC joint along the lines of Langer. Visualization of the AC joint as well as the coracoid is possible. The deltotrapezial fascia is split along the midline of the clavicle and elevated as two full-thickness flaps.

     

     

    The distal end of the clavicle may need to be freed from the trapezius muscle, under the acromion, or rarely coracoid.

     

    Interposition of soft tissue may prevent anatomic reduction of the AC joint.

     

     

    P.107

     

     

     

    TECH FIG 2 • A. Grafts need tendon-grasping sutures at both ends for ease of passage around the coracoid and through bone tunnels. B. In our alternative method, grafts that are to be fixed to the coracoid are folded so that there is one short limb and one long limb. A no. 2 nonabsorbable suture is placed through the

    doubled-over tendon graft in a Krackow manner. Tendon ends are bulleted for ease of passage through bone tunnels.

  • Graft Preparation

 

An allograft (semitendinosus or anterior tibialis) or autograft (semitendinosus) can be used for this procedure (TECH FIG 2A). (See the Techniques section of Chaps. 49 and 50 for a description of obtaining a semitendinosus autograft.)

 

Tendon ends are bulleted for easy passage through bone tunnels.

 

 

 

TECH FIG 3 • A. The graft is looped around the coracoid. B. A suture passer can be used to safely loop the graft and a nonabsorbable suture around the coracoid base. C. In the alternative technique, a bone tunnel that approximates the diameter of the graft (usually 6 to 7 mm) is made in the coracoid. One limb of the Krackow suture is placed, and the doubled-over tendon is passed through the PEEK screw and driver (top inset). While traction is held with this suture, the tenodesis driver is advanced to touch the tendon graft (bottom inset), and the entire tendon, driver, and screw complex is placed into the coracoid bone tunnel.

 

 

A whipstitch or grasping suture is placed in the two free ends of the tendon for graft passage through bone tunnels. The tendon is sized using standard tendon sizers (usually 5 or 6 mm).

 

The graft is ready for use if the surgeon is performing our preferred loop technique.

 

An alternative method is interference screw fixation of the graft to the coracoid process (tenodesis technique). In this option, the graft is folded with one short limb (about 3 inches) and a limb containing the remaining length of the tendon. A no. 2 ultra-high-strength nonabsorbable suture is placed through the doubled-over tendon graft in a Krackow manner (TECH FIG 2B).

Coracoid Preparation and Graft Fixation to Coracoid

 

The graft can be fixed to the coracoid by either looping the graft around the base of coracoid (Loop technique) or by the tenodesis of the graft into the base of coracoid with the use of an interference screw (Tenodesis technique).

 

Loop technique (our preferred technique)

 

Soft tissue dissection is performed to expose the coracoid process from the base to the tip, including dissection of the medial and lateral margins of the coracoid.

 

A suture can be looped around the base of the coracoid process using an aortic cross-clamp (Satinsky clamp) or a suturepassing device (Arthrex, Inc., Naples, FL). The clamp or suturepassing device is passed from the medial to lateral direction.

 

A loop is created at one end of this suture and is used to pass the graft and collagen-coated no. 2

FiberWire (Arthrex, Inc.) around the coracoid.

 

The graft provides biologic form of fixation and collagencoated no. 2 FiberWire provides the nonbiologic form of fixation across the CC space (TECH FIG 3A,B).

 

P.108

 

Tenodesis technique (TECH FIG 3C)

 

The diameter of the doubled-over portion of the graft is measured with a standard tendon-measuring device. Using this number, the appropriate cannulated reamer is chosen (6 or 7 mm).

 

The surgeon should use a smaller reamer diameter first and ream up in size if necessary.

 

Finger palpation of both lateral and medial portions of the coracoid process and drilling into the coracoid base under direct visualization with a cannulated reamer guide pin are completed.

 

One limb of the Krackow suture is passed through a 5.5- × 8-mm nonabsorbable radiolucent tenodesis screw and driver using a Nitinol wire.

 

The tenodesis driver is advanced to touch the tendon graft, and the entire tendon, driver, and screw complex is placed into the coracoid bone tunnel until 15 mm of the Krackow suture disappears.

 

The sutures from the graft are tied together over the existing interference screw, giving both interference screw and suture anchor advantages.

Clavicle Preparation

 

Bone tunnels are drilled in the clavicle for the reconstruction of the conoid and trapezoid ligament attachment on the clavicle.

 

To recreate the conoid ligament, a cannulated guide pin is placed approximately 45 to 50 mm medial from the distal end of the clavicle. Alternatively, the conoid tubercle on the inferior surface of the lateral third of clavicle can also be used as an anatomic landmark for this guide pin placement. The drill hole should be drilled as posterior as possible, taking into consideration the space needed to not “blow out” the posterior cortical rim during subsequent reaming.

 

A 5-mm cannulated reamer is used to create the tunnel (TECH FIG 4).

 

If there is a question of what size of reamer to use, starting with the smallest reamer is always a good technique; if necessary, the surgeon can ream up.

 

The surgeon reams in under power. The surgeon disconnects the power driver and pulls the reamer out manually to ensure that the tunnel is a perfect circle and not widened by uneven reaming.

 

The depth of the tunnel is measured for appropriate screw length placement.

 

 

 

TECH FIG 4 • A. Anatomic reconstruction of the CC ligaments. For conoid ligament reconstruction, a guide pin is placed in the clavicle 45 mm from the AC joint in a posteromedial position. For trapezoid ligament reconstruction, a guide pin is placed 30 mm from the AC joint centered on the clavicle. B. After confirming the positions of the pins, a 5-mm cannulated drill is used to drill the clavicle. Care should be taken to place the conoid tunnel as far posterior as possible without violating the posterior cortex during reaming.

 

 

The same procedure is repeated for the trapezoid ligament, which is a more anterior and lateral structure than the conoid ligament.

 

The bone tunnel for conoid ligament is centered on the clavicle, approximately 15 mm lateral to the center portion of the previous tunnel but definitely 25 to 30 mm medial to the AC joint.

 

We have recently shown that the bone mineral density in the lateral third of the clavicle progressively

increases from lateral to medial direction.5 The optimal bone density was found in the anatomic insertion area of the CC ligaments between 20 and 50 mm from the lateral end of the clavicle. The distance from the AC joint demonstrated a positive correlation to the pullout strength of the graft in cadaveric

clavicles.5

Graft Fixation to the Clavicle and Reconstruction of Coracoclavicular Space and Acromioclavicular Joint Anatomy

 

The limbs of the graft are crossed over the coracoid and one limb of the biologic graft is placed through the posterior bone tunnel (represents the conoid ligament). The other limb is passed through the anterior bone tunnel in the same fashion (represents the trapezoid ligament; TECH FIG 5A,B). If there is significant posterior displacement of clavicle, the limbs of the graft are not crossed under the clavicle.

 

The no. 2 collagen-coated FiberWire looped around the coracoid is also passed through the tunnels for providing nonbiologic augmentation of the repair.

 

Reduction maneuver for AC join is performed. This involves an upward-directed force on the scapulohumeral complex combined with the use of a large, pointed reduction forceps placed on the coracoid process and the clavicle to reduce the AC joint (TECH FIG 5C).

 

Fluoroscopy is used to confirm adequate reduction of the AC joint.

 

The graft is pulled on cyclically multiple times and passed through the tunnels back and forth to reduce any displacement that might occur after fixation.

 

This step is critical to ensure that there is no migration or movement after the fixation is complete.

 

Nevertheless, we often overreduce the AC joint by 2 to 3 mm with the knowledge that a few millimeters of displacement still occurs.

 

The graft is positioned so that the graft tail representing the conoid ligament is left 2 cm proud from the superior margin of the clavicle.

 

P.109

The long tail of the graft exits the trapezoid tunnel and will later be used to augment the AC joint repair if indicated (see TECH FIG 5B).

 

 

 

TECH FIG 5 • A,B. The free ends of the graft are crossed and passed through the clavicle. The graft is pulled back and forth through the tunnels and cyclic loading is placed on the graft. A short tail is left superior to the clavicle for the conoid ligament while the remainder of the graft exits the trapezoid tunnel, with one end left longer than the other. A 5.5- × 8-mm nonabsorbable radiolucent screw is used for interference fixation of the graft to the conoid tunnel in the clavicle. Cyclic tension is again placed on the graft. While holding reduction and the graft under tension, another 5.5- × 8-mm nonabsorbable radiolucent screw (PEEK screw) is placed in the anterolateral trapezoid tunnel. C. The radiographic image of reduction with position of the pointed reduction forceps used for reduction of the AC joint.

 

 

With traction placed on the graft, ensuring its tautness, nonabsorbable screw of appropriate size and length is placed in the posteromedial tunnel anterior to the conoid ligament graft. We prefer a 5.5 size PEEK screw.

 

Again, the graft is cyclically loaded multiple times. While holding reduction and tension on the ligament, another nonabsorbable screw is placed in the lateral trapezoid tunnel anterior▪ to the trapezoid ligament

graft. Again, we prefer a 5.5 PEEK screw.

 

With both grafts secured, the no. 2 collagen-coated FiberWire is tied over the top of the clavicle, becoming the nonbiologic fixation for the reduced AC joint.

 

The deltotrapezial fascia is meticulously closed using interrupted nonabsorbable sutures, taking care to

leave the knots on the posterior aspect of the trapezius

 

A simple suture can be used to bury the knot if it is prominent.

  • Distal Clavicle Excision versus Acromioclavicular Joint Repair

     

    For acute injuries, our preferred approach is to perform an AC joint repair.

     

    The AC joint is exposed. Simple or figure-8 sutures using a no. 0 nonabsorbable suture are used to repair the AC joint capsule and ligaments primarily.

     

    The posterior and superior ligaments are key in preventing posterior and superior displacement of the clavicle.

     

    The AC joint repair can be augmented by using the limb of the graft used for the CC ligament repair.

     

    The short limb of the graft exiting the medial tunnel is folded laterally and sewn to the base of the▪ graft exiting the trapezoid tunnel in series (TECH FIG 6A).

     

    The long limb exiting the lateral (trapezoid) tunnel is taken laterally and looped on top of the AC joint and used for augmentation of the AC joint capsule repair (TECH FIG 6B,C).

     

    In chronic dislocations, two options exist.

     

    One approach is to repair the AC joint as detailed earlier.

     

    An alternative approach is to perform a distal clavicle excision especially if AC joint arthrosis is a concern.

     

     

    An oscillating saw is used to remove 1 cm of the distal clavicle. The posterior cortical rim of the clavicle is beveled.

     

     

    P.110

     

     

     

    TECH FIG 6 • A. The short limb of the graft representing the conoid ligament is folded laterally and sewn to the graft base representing the trapezoid ligament. B,C. The long limb representing the trapezoid ligament can be taken laterally and used to augment the AC ligament fixation.

  • Modified Weaver-Dunn Procedure

     

    Diagnostic arthroscopy is done if concomitant injuries are suspected.13

     

    The incision is centered at 1.5 cm from the AC joint starting at the posterior clavicle in a curvilinear fashion toward the coracoid along the Langer lines.

     

    The incision is sometimes placed obliquely to allow full visualization of the AC joint laterally and coracoid process medially.

     

    Superficial skin bleeders are controlled down to the deep fascia with a needle-tip Bovie. Full-thickness cutaneous flaps are elevated to define the underlying deltotrapezial fascia attachment onto the clavicle and acromion.

     

    Full-thickness fascioperiosteal flaps are elevated from the midline of the clavicle both posteriorly and anteriorly, skeletonizing▪ the clavicle (TECH FIG 7). One can identify a raphe between the deltoid and trapezius attachments on clavicle and acromion, which serves as a good avascular plane for dissection.

     

     

     

    TECH FIG 7 • Transfer of the acromial attachment of the coracoacromial (CA) ligament, the modified Weaver-Dunn procedure. Full-thickness flaps are made from the midline of the clavicle both posteriorly and anteriorly, skeletonizing the clavicle. Periosteal flaps are elevated and a tagging suture can be placed at the medialmost aspect of the flap for accurate closure. A small portion of the anterior deltoid is reflected from the anterior acromion to expose the CA ligament. (Adapted from Galatz LM, Williams GR Jr.

    Acromioclavicular joint injuries. In: Bucholz RW, Heckman JD, Court-Brown C, eds. Rockwood and Green's Fractures in Adults, vol 2. Philadelphia: Lippincott Williams & Wilkins, 2006:1354.)

     

     

    Alternatively, a “hockey stick” incision can be made laterally from the acromion along the midportion of the clavicle, ending in a hockey stick fashion down toward the coracoid.

     

    Periosteal flaps are elevated and a tagging suture can be placed at the medialmost aspect of the flap for accurate closure.

    Biologic Fixation: Coracoacromial Ligament Transfers

     

    The CA ligament is dissected out, especially laterally.

     

    The CA ligament is detached from its footprint that extends posteriorly on the acromion (TECH FIG 8A).

     

     

    P.111

     

     

     

    TECH FIG 8 • A. The ligament is released from the acromion and sutures are placed at the end. B. After a distal clavicle resection, two 2-mm unicortical drill holes are placed in the posterosuperior surface of the distal clavicle, exiting through the intramedullary canal. (Adapted from Galatz LM, Williams GR Jr.

    Acromioclavicular joint injuries. In: Bucholz RW, Heckman JD, Court-Brown C, eds. Rockwood and Green's Fractures in Adults, vol 2. Philadelphia: Lippincott Williams & Wilkins, 2006:1354.)

     

     

    Two heavy nonabsorbable sutures are placed at the end of the ligament using a whipstitch.

     

    The CA ligament is held directly superiorly and the corresponding area is marked on the clavicle.

     

    This marks the amount of clavicle that needs to be resected to allow easy passage of the CA ligament without sharp turns.

     

    If adequate arthroscopic resection has not already been performed, an oscillating saw is used to make an oblique cut on the clavicle, leaving more bone superiorly rather than inferiorly, at the level of the previously marked site.

     

    An intramedullary pocket is curetted inside the clavicle for the CA.

     

    The AC intra-articular disc is resected, leaving the AC ligaments undisturbed.

     

    A 2.0-mm drill is used to make two drill holes in a cruciate fashion (lateral clavicle anteriorly, medial clavicle posteriorly) 20 mm medial to the distal cut end of the clavicle (TECH FIG 8B).

     

    A wire loop is used to pass each limb of the CA ligament suture through the end of the clavicle and out the drill hole made superiorly.

     

    For augmentation of CA ligament transfer, a 3.5-mm drill hole is made into the clavicle medial to the previously made drill holes for the CA ligament.

     

    For nonbiologic augmentation, a suture cord is constructed.

     

    The surgeon takes three no. 1 absorbable sutures clamped at both ends. One clamp is turned clockwise while holding the other end until the sutures are intertwined together for the entire length of the sutures.

     

    This is done with two other sets of three sutures.

     

    The three sets are intertwined counterclockwise in the same fashion, resulting in a cord of nine total sutures. The suture cord is passed around the coracoid and through the 3.5-mm drill hole in the clavicle.

     

    For biologic augmentation, an autograft or allograft can be used.

    Reduction and Fixation

     

    Reduction maneuver for AC joint: Upward displacement of the scapulohumeral complex combined with the use of a large, pointed reduction forceps placed on the coracoid process and the clavicle are used to reduce the AC joint.

     

    Slight overreduction during fixation is recommended.

     

    After reduction is achieved, the surgeon pulls the suture limbs of the CA ligament reconstruction, exiting the bone tunnels, and ties them on the superior surface of the clavicle (TECH FIG 9).

     

    The pocket for the CA ligament must be long enough so that after anatomic reduction, the graft is nice and taut.

     

    If the suture cord was used, the suture cord that was passed around the coracoid and through the clavicle is tied.

     

    The surgeon should attempt to place the knot in the least prominent area.

     

    The ends of the suture cord are unraveled and each individual suture limb is tied to prevent unraveling of the cable.

     

    Finally, all free suture ends are cut.

     

    If ligament augmentation was used, the ligament is wrapped in a figure-8 fashion and sutured to itself using heavy nonabsorbable sutures.

     

    Closure is the same as the ACCR technique (see TECH FIG 6C).

     

     

     

    TECH FIG 9 • A. Using a curette, a pocket is made inside the clavicle for the coracoacromial (CA) ligament. The CA ligament is transferred to the intramedullary canal. The sutures are placed through the drill holes and tied over the top of the clavicle. This pocket has to be large enough so that after reduction of the joint, the CA ligament can be pulled inside without any impediment. If this is done correctly, the ligament should be taut and not overstuffed inside the pocket. (Adapted from Galatz LM, Williams GR Jr. Acromioclavicular joint injuries. In: Bucholz RW, Heckman JD, Court-Brown C, eds. Rockwood and Green's Fractures in Adults, vol

    2. Philadelphia: Lippincott Williams & Wilkins, 2006:1354.)

     

     

     

    P.112

     

     

    PEARLS AND PITFALLS

     

    Positioning and approach

    • The surgeon should make sure that the patient's head can be repositioned to the side, allowing room for conoid tunnel drilling.

    • An alternative is to displace the clavicle anteriorly with a towel clip to allow access for conoid tunnel drilling.

    • The deltoid and trapezial fascia are tagged for good repair.

 

Graft management

  • Graft ends are bulleted to allow for easy graft passage.

  • Sutures are passed under the coracoid either from medial to lateral direction.

  • If passing lateral to medial, the surgeon should make sure that the medial coracoid base is exposed and should insert a Darrach retractor on the medial base to “catch” the passing device.

  • Once the graft is passed under the coracoid, the limbs are crossed before they are passed through the clavicle tunnels.

     

    Tunnel preparation and graft fixation

    • The surgeon should ream in under power. When the power driver is disconnected, the surgeon should pull the reamer out manually to ensure that the tunnel is a perfect circle and not widened by uneven reaming.

    • Starting with the smallest reamer necessary is always a good technique. The surgeon can ream up at half-millimeter increments if the graft is too large.

    • The tenodesis screw is inserted anterior to the graft to equally recreate posterior CC ligaments.

 

POSTOPERATIVE CARE

 

The goals of postoperative rehabilitation are to restore and reinforce the stability to the AC joint through strength training of the supporting muscles of the shoulder girdle and achieve pain-free movement of shoulder.3

 

Postoperative support with a Lerman Shoulder Orthosis (DJO Inc., Vista, CA) or a Gunslinger Shoulder Orthosis (Hanger Prosthetics & Orthotics, Inc., Bethesda, MD) is used for 6 to 8 weeks. These braces are recommended to counter the pull on the shoulder complex by gravity. The importance of immobilization and protection in a brace should be emphasized to the patient as it is critical in preventing postoperative failure.

 

Early intervention is directed toward reducing pain and inflammation to allow strength-based exercise to begin as soon as possible. For the first 6 to 8 weeks, the brace may be removed for grooming and supine gentle

passive range of motion only.

 

 

Active and passive range-of-motion exercises are started at 8 weeks after surgery. If painless range of motion is obtained, strength training is started at 12 weeks.

 

OUTCOMES

 

Anatomic CC reconstruction

 

 

Martetschlager et al8 recently reported outcomes on anatomic CC reconstruction (tendon graft or cortical fixation button) in 59 shoulders with a mean age of approximately 43 years. At a mean follow-up of 2.4 years, the 12- and 24-month construct survivorship was calculated to be 86.2% and 83.2%, respectively. There was a significant improvement in the American Shoulder and Elbow Surgeons (ASES) scores and SF-12 physical component scores in cohort of patients without significant complications. The overall complication rate was 27.1%.

 

Weaver-Dunn procedure

 

Outcomes are difficult to compare due to the variations in the Weaver-Dunn method used and the makeup of the type of patients and severity of injury within study groups. The original Weaver-Dunn procedure (isolated CA ligament transfer) has led to modified Weaver-Dunn procedure in which the CA ligament transfer is combined with AC joint or CC space fixation.

 

Rauschning et al14 reported 12 acute and 5 chronic type III AC joint injuries treated by the Weaver-Dunn procedure (isolated CA ligament transfer). At follow-up 1 to 5 years after the operation, all patients had stable and painless shoulders with resumption of full activities and functionally excellent results even though there was 21% loss of reduction (level IV evidence).

 

Tienen et al20 presented 21 patients with Rockwood type V AC joint dislocations who underwent a modified Weaver-Dunn procedure with clavicle reduction and AC joint fixation using absorbable braided sutures. At a mean follow-up of 35.7 months, 18 patients had returned to their sports without pain within

2.5 months after operation; the average Constant score at last follow-up was 97. Radiographs taken at this time showed residual subluxation in two patients and, in one patient, redislocation of the joint that occurred because of infection (level IV evidence).

 

When chronic and acute repairs of type III AC joint injuries were studied, patients with early repair were

significantly better after 3 months. In a study by Weinstein et al,22 26 of 27 (96%) patients with early repairs and 13 of 17 (77%) patients with late reconstructions achieved satisfactory results with an average 4-year follow-up (level IV evidence).

 

COMPLICATIONS6,8,10

 

 

Loss of reduction and recurrence of deformity Infection

 

Adhesive capsulitis

 

ACCR specific complications: graft failure, coracoid fracture, clavicle fracture, clavicular or coracoid osteolysis, hypertrophic distal clavicle, brachial plexopathy, broken hardware complications (broken hardware, symptomatic hardware), osteoarthritis of AC joint

 

Modified Weaver-Dunn specific complications: hardware complications (wire migration, acromion fracture,

osteolysis of acromion, broken hardware), foreign body reaction to synthetic material

 

 

P.113

REFERENCES

  1. Berg EE, Ciullo JV. The SLAP lesion: a cause of failure after distal clavicle resection. Arthroscopy 1997;13:85-89.

     

     

     

  2. Bradley JP, Elkousy H. Decision making: operative versus nonoperative treatment of acromioclavicular joint injuries. Clin Sports Med 2003;22:277-290.

     

     

  3. Cote MP, Wojcik KE, Gomlinski G, et al. Rehabilitation of acromioclavicular joint separations: operative and nonoperative considerations. Clin Sports Med 2010;29(2):213-228.

     

     

  4. Debski RE, Parsons IM, Woo SL, et al. Effect of capsular injury on acromioclavicular joint mechanics. J Bone Joint Surg Am 2001;83A:1344-1351.

     

     

  5. Geaney LE, Beitzel K, Chowaniec DM, et al. Graft fixation is highest with anatomic tunnel positioning in acromioclavicular reconstruction. Arthroscopy 2013;29(3):434-439.

     

     

  6. Geaney LE, Miller MD, Ticker JB, et al. Management of the failed AC joint reconstruction: causation and treatment. Sports Med Arthrosc 2010;18(3):167-172.

     

     

  7. Klimkiewicz JJ, Williams GR, Sher JS, et al. The acromioclavicular capsule as a restraint to posterior translation of the clavicle: a biomechanical analysis. J Shoulder Elbow Surg 1999;8:119-124.

     

     

  8. Martetschlager F, Horan MP, Warth RJ, et al. Complications after anatomic fixation and reconstruction of the coracoclavicular ligaments. Am J Sports Med 2013;41:2896-2903.

     

     

  9. McFarland EG, Blivin SJ, Doehring CB, et al. Treatment of grade III acromioclavicular separations in professional throwing athletes: results of a survey. Am J Orthop 1997;26:771-774.

     

     

  10. Milewski MD, Tompkins M, Giugale JM, et al. Complications related to anatomic reconstruction of the coracoclavicular ligaments. Am J Sports Med 2012;40(7):1628-1634

     

     

  11. Mouhsine E, Garofalo R, Crevoisier X, et al. Grade I and II acromioclavicular dislocations: results of conservative treatment. J Shoulder Elbow Surg 2003;12:599-602.

     

     

  12. Phillips AM, Smart C, Groom AF. Acromioclavicular dislocation. Conservative or surgical therapy. Clin Orthop Relat Res 1998;(353):10-17.

     

     

  13. Ponce BA, Millett PJ, Warner JP. Acromioclavicular joint instability: reconstruction indications and techniques. Op Tech Sports Med 2004;12:35-42.

     

     

  14. Rauschning W, Nordesjo LO, Nordgren B, et al. Resection arthroplasty for repair of complete acromioclavicular separations. Arch Orthop Trauma Surg 1980;97:161-164.

     

     

  15. Rios C, Arciero R, Mazzocca A. Anatomy of the clavicle and coracoid process for reconstruction of the coracoclavicular ligaments. Am J Sports Med 2007;35:811-817.

     

     

  16. Rockwood CA, Williams GR, Young DC. Disorders of the acromioclavicular joint. In: Rockwood CA, Matsen F, eds. The Shoulder, ed 2. Philadelphia: WB Saunders, 1990:495-554.

     

     

  17. Schlegel TF, Burks RT, Marcus RL, et al. A prospective evaluation of untreated acute grade III acromioclavicular separations. Am J Sports Med 2001;29:699-703.

     

     

  18. Sood A, Wallwork N, Bain GI. Clinical results of coracoacromial ligament transfer in acromioclavicular dislocations: a review of published literature. Int J Shoulder Surg 2008;2(1):13-21.

     

     

  19. Tibone J, Sellers R, Tonino P. Strength testing after third-degree acromioclavicular dislocations. Am J Sports Med 1992;20: 328-331.

     

     

  20. Tienen TG, Oyen J, Eggen PJ. A modified technique of reconstruction for complete acromioclavicular dislocation: a prospective study. Am J Sports Med 2003;31:655-659.

     

     

  21. Walton J, Mahajan S, Paxinos A, et al. Diagnostic values of tests for the acromioclavicular joint pain. J Bone Joint Surg Am 2006;86A:807-812.

     

     

  22. Weinstein DM, McCann PD, McIlveen SJ, et al. Surgical treatment of complete acromioclavicular dislocations. Am J Sports Med 1995;23:324-331.