Rotator Cuff Deficiency ISAKOS Instructional Course. 1.) Dr. DiGiacomo (12 minutes) Rotator Cuff Deficiency: From Dysfunction to the Lesion

Transcription

1 Rotator Cuff Deficiency ISAKOS Instructional Course 1.) Dr. DiGiacomo (12 minutes) Rotator Cuff Deficiency: From Dysfunction to the Lesion 2.) Dr. Sugaya (12 minutes) Double Row Versus Single Row Repair for Rotator Cuff Repair 3.) Dr. Spang (12 minutes) Cuff Deficiency: Indications for Partial Repair versus Patches versus Latissimus Dorsi Transfer vs. Arthroplasty 4.) Dr. Randelli (12 minutes) The Role of Platelet Rich Plasma (PRP) in Cuff Repair 5.) Dr. Burkhart (12 minutes) Mobilization Techniques for Repair of Massive Cuff Tears 6.) Discussion (30 minutes)

2 ISAKOS 2011 Rotator Cuff Deficiency: Large To Massive Rotator Cuff Tears Stephen S. Burkhart, MD Samuel Koo, MD San Antonio, Texas PRE-OPERATIVE CONSIDERATIONS INTRODUCTION During the past 10 to 15 years, there has been a dramatic evolution in the arthroscopic treatment of massive rotator cuff tears. In the past, many massive rotator cuff tears (>5cm in greatest dimension as defined by DeOrio and Cofield)(1) were regarded as irreparable. Today, we have gone from being unable to repair any rotator cuff tears arthroscopically to being able to repair virtually all rotator cuff tears, even massive ones, arthroscopically. Massive rotator cuff tears make up approximately 20% of all cuff tears(2) and a considerably greater percentage (80%) of recurrent rotator cuff tears.(3) In the early 1990s, the recommendation often included simple debridement of the massive tears.(4) While debridement of massive tears has been relatively successful in terms of pain relief, overhead function is often not an attainable goal particularly in patients that do not have balanced force couples.(5, 6) Advancement in arthroscopic shoulder surgery has now improved our understanding of tear patterns and has offered new opportunities and capabilities in terms of rotator cuff repair techniques.(2) Understanding tear patterns is particularly important. Without a comprehensive understanding of tear patterns, the traditional repair techniques

3 have focused on covering the hole. This was usually accomplished via an open or mini-open approach and subsequent extensive release of the cuff muscles to achieve enough mobilization to allow a repair to the bone. This medial-to-lateral technique did not respect the true pattern of pathology. Also, the extensive mobilization required can result in over tensioning of the rotator cuff and its subsequent failure.(7) This can lead to damage to the suprascapular nerve, thereby leaving a repaired cuff completely nonfunctional.(8) This may explain the traditionally poor results repairing primary and recurrent massive rotator cuff tears via an open approach(1, 9, 10) or an arthroscopic approach based on a purely medial-to-lateral mobilization and repair.(11) More recently, some have proposed the use of orthobiological tissue patches to cover the hole in massive rotator cuff tears.(12) Again, this approach does not respect the biomechanics of the rotator cuff and is therefore doomed to failure. Unless the rotator cuff tendons can be appropriately tensioned to achieve an optimal position along the muscle length-tension curve, ultimate improvement in function is unlikely. While truly irreparable rotator cuff tears do exist (tears with 75% or greater fatty infiltration)(13), the majority of patients with massive rotator cuff tears can obtain a good cuff closure and clinical result. The key to repairing the traditional irreparable tear is in understanding the pattern of the tear and then knowing how to deal with each pattern. With a suitable knowledge of tear patterns and with adequate and appropriate mobilization and repair techniques, as outlined below, most massive rotator cuff tears can and should be repaired. This leads to not only improved pain relief but also a return of a significant amount of function, usually including overhead function.(2, 3)

4 PRINCIPLES AND ANATOMY Before we discuss rotator cuff repair, it would be instructive to review the principles and anatomy that guide our reconstructive strategies. Three key areas to understand are: 1. Force couples; 2. The rotator cable/crescent complex; and 3. Rotator cuff tear patterns. FORCE COUPLES A primary function of the rotator cuff is to balance the force couples about the glenohumeral joint. A force couple is a pair of forces that act on an object and cause it to rotate. For any object to be in equilibrium, the forces must create moments about a center of rotation that are equal in magnitude and opposite in direction. In the situation where the center of rotation is equidistant from the point of application of each force, the forces must be equal and opposite in direction for equilibrium to exist. In the shoulder, the coronal plane force couple was described by Inman et al.(14) This force couple is a result of the balance of moments created by the deltoid versus those created by the intact portions of the inferior rotator cuff. (Fig. 1) During abduction, the coronal plane force couple will only be balanced if the line of action of the rotator cuff force is below the center of rotation of the humeral head, so that it can oppose the moment created by the deltoid. Balancing the coronal plane force couple is essential because this maintains a stable fulcrum for glenohumeral joint motion. An equally important force couple is the transverse plane force couple. This force couple consists of the subscapularis anteriorly, balanced against the posterior rotator cuff. (Fig. 2) This force couple is relevant in massive rotator cuff tears in which the tear may

5 extend more posteriorly, leaving only a remnant of intact posterior cuff. In many cases, the posterior rotator cuff is so weak that it cannot balance the anterior moment created by the large subscapularis tendon. Furthermore, a large posterior rotator cuff tear can result in such a deficiency that the moment created by the inferior rotator cuff is also insufficient to maintain equilibrium in the coronal plane. This, then, can result in anterior and superior translation of the humeral head and the inability to maintain a stable fulcrum of motion. Therefore, when faced with a rotator cuff tear, the primary goal of surgery is to balance the force couples in the transverse and coronal planes and not necessarily to cover the hole. Again, the goal of rotator cuff repair is not to bring a medialized tendon stump laterally to bone, but to restore the balance of forces that control shoulder motion. SUSPENSION BRIDGE ANALOGY When arthroscopically viewed from the glenohumeral joint, the articular surface of the intact rotator cuff demonstrates an arching, cable-like thickening of the capsule surrounding a thinner crescent of tissue that inserts into the greater tuberosity of the humerus.(15) This cable-like structure, which represents a thickening of the coracohumeral ligament, is consistently located at the avascular zone margin of the rotator cuff. (Fig. 3) It extends from its anterior attachment into the greater tuberosity of the humerus just posterior to the biceps tendon, to its posterior attachment near the inferior border of the infraspinatus. This rotator cable potentially serves a protective role by stress-shielding the thinner, avascular crescent tissue, analogous to a load-bearing suspension bridge.

6 Similar to the intact rotator cuff, a rotator cuff tear can also be modeled after a suspension bridge where the free margin of the tear corresponds to the cable and the anterior and posterior attachments of the tear correspond to the supports at each end of the cable s span. This model would predict, and subsequent studies have shown, that despite a tear in the avascular zone of the supraspinatus tendon, the supraspinatus muscle could still exert a compressive effect on the glenohumeral joint by means of its distributed load along the span of the suspension bridge configuration.(16) The study by Halder et al. supports the concept that in small and medium sized rotator cuff tears, the rotator cuff muscle forces are effectively transmitted along the rotator cuff cable, bypassing the torn supraspinatus tendon. That is why certain rotator cuff tears, even massive ones, can demonstrate functional kinematics and why after rotator cuff repair, good results can be achieved even when a water-tight closure is not obtained.(11, 17) Furthermore, the implication of the cable-crescent concept contradicts the historical principle of covering the hole, particularly when using techniques such as tendon transfers to obtain closure of massive, irreparable rotator cuff tears. Other authors have advocated the use of tendon transfers, including the infraspinatus and subscapularis, to cover rotator cuff defects in massive tears.(17) Transferring these muscles superiorly, however, significantly alters the normal mechanics of the rotator cuff. TEAR PATTERNS The first step in approaching massive rotator cuff tears is recognizing the pattern of the tear. This point cannot be overemphasized. Arthroscopy has greatly enhanced our understanding of rotator cuff tear patterns. Unlike traditional open surgery, which is

7 limited by an anterolateral exposure, arthroscopy is not restricted by spatial constraints. Using arthroscopic techniques, rotator cuff tears can now be assessed and treated from several different angles with minimal disruption to the overlying deltoid. This new perspective on evaluating and treating rotator cuff tears has led to the recognition of four major types of rotator cuff tears. 1. Crescent-shaped tears. 2. U-shaped tears. 3. L- shaped and reverse-l shaped tears. 4. Massive contracted, immobile tears. Crescent-shaped tears are the simplest of all tears and although they can be massive, these tears do not typically retract medially to a significant degree. These tears demonstrate excellent mobility from a medial-to-lateral direction and can be repaired directly to bone with minimal tension to the anatomic bone bed. (Fig. 4) In contrast, U-shaped rotator cuff tears extend much farther medially than crescent-shaped tears, with the apex of the tear adjacent to or medial to the glenoid rim. Recognizing this tear pattern is critical, because attempting to medially mobilize and repair the apex of the tear to a lateral bone bed will result in over tensioning of the rotator cuff margin and subsequent failure. (Fig. 5) These tears demonstrate significant mobility from an anterior to posterior direction and should be initially repaired in a side-to-side fashion using the biomechanical principle of margin convergence. L-shaped and reverse-l-shaped tears are similar to U-shaped tears. These are usually massive tears with a longitudinal component in the direction of the fibers of the rotator cuff and a transverse component along the lateral cuff insertion. (Fig. 6) One of the leaves (usually the posterior leaf), is more mobile than the other leaf and can be easily brought to the bone bed.

8 These first three tear patterns represent about 90% of posterosuperior rotator cuff tears and can be repaired using the principles outlined here. Thus, most rotator cuff tears, even massive tears, can be repaired without extensive mobilization with an understanding and recognition of these tear patterns. Repairing tears according to their tear pattern can lead to excellent results.(2) In the fourth tear pattern, the massive, contracted, immobile rotator cuff tear, other techniques must be used. HISTORY AND PHYSICAL EXAMINATION As with all orthopedic conditions, a thorough assessment should begin with the history and physical examination. The chronicity of the tear is an important element of the history and is often difficult to fully ascertain. Although a history of a traumatic event, such as a fall onto an outstretched hand, is often reported as the initiating event, many patients with a massive rotator cuff tear will give a history of a long period of shoulder problems. These patients may have had a chronic rotator cuff tear that still allowed a balanced force couple across the glenohumeral joint. At the time of their recent trauma, they may extend their tears to the point where they lose overhead function. This is important to note in the history because patients with a long period of shoulder symptoms are more likely to have rotator cuff tears that are large and require mobilization for repair. The subscapularis exam is a key element to the shoulder examination that is frequently untested. The lift-off test is not positive until at least three fourths of the subscapularis tendon is detached and, therefore, is not a good test for upper subscapularis

9 tears(18). The bear hug test is the most sensitive test for a torn subscapularis (particularly a partial tear involving only the upper subscapularis).(19) In this test, the patient places the hand of the affected side on the opposite shoulder with the fingers extended and the elbow elevated into a forward position. The examiner then tries to pull the patient s hand off the shoulder perpendicular to the plane of the forearm as the patient resists. (Fig. 7) If the examiner is able to lift the patient s hand off the shoulder, this is a positive finding and is suggestive of at least a partially torn subscapularis tendon. Other tests for the subscapularis include the belly-press and Napoleon test.(20) DIAGNOSTIC IMAGING Plain radiographs are important in initial assessment. The status of the glenohumeral joint must be determined because patients who suffer from moderate to severe glenohumeral degenerative joint disease (DJD) will be less likely to benefit significantly from arthroscopy and rotator cuff repair. In addition to arthritis, the surgeon should examine the plain films for evidence of superior migration of the humerus. The next step in preoperative planning is to obtain an MRI of the shoulder. The MRI can give the surgeon a good idea of the severity of the cuff tear and reveals associated pathologies. It is also helpful in surgical planning as the amount of fatty infiltration can be determined, as we will discuss in the subsequent pages. INDICATIONS/CONTRAINDICATIONS Proper patient selection is important in any type of surgery. It is particularly vital in arthroscopic repair of massive rotator cuff tears. In the evaluation of a patient with a

10 massive rotator cuff tear, the surgeon must weigh numerous factors in the decision making process. First and foremost are patient related factors, such as the patient s general health status and comorbidities. Also, important is the patient s current and desired level of function. However, for most people with massive rotator cuff tears, surgery remains the best option to achieve improvement in both pain and function. Traditionally, fatty infiltration of greater than 50% on preoperative MRI has been considered a poor prognostic indicator for rotator cuff repairs.(22-24) These patients have been discouraged from undergoing cuff repair with the assumption that surgical repair would not improve their outcome. In the senior author s practice, assessment of fatty infiltration within the muscle belly of the infraspinatus is critical, as it impacts outcome.(13) Muscle imparts elasticity to the rotator cuff and without adequate muscle tissue it would be difficult, if not impossible to repair the tendon to the greater tuberosity. Lo and Burkhart reported the results of repair of massive immobile rotator cuff tears that required the interval slide technique.(21) The patients demonstrated significant improvements in pain, active forward elevation, active external rotation, strength and function. More recently, the senior author evaluated the outcomes of massive cuff repairs and correlated these outcomes to preoperative MRI findings.(13) The data suggest that patients who have greater than 75% fatty infiltration do indeed have a guarded prognosis for significant improvement as only 40% of these patients demonstrated clinical improvement. This is essential to know prior to surgery because these patients can be informed of their less favorable prognosis. They may choose not to proceed with surgical intervention given their limited probability of functional improvement. However, patients with 50% to 75% fatty infiltration actually improved significantly after rotator cuff repair.

11 In fact, 100% (17/17) of patients with less than 75% fatty infiltration had significant clinical and functional improvement after rotator cuff repair. Thus, in contradistinction to Goutallier s cut-off of 50%, we consider all patients with less than 75% fatty infiltration on the MRI to be potential surgical candidates. One area in which massive contracted rotator cuff tears are frequently encountered is during revision rotator cuff repair. Many authors have reported the results of revision rotator cuff surgery done through an open approach.(1, 9, 10, 22) Overall, these studies have demonstrated that while frequently effective in terms of pain relief, functional improvements have been slight. Recently, Lo et al has reported on the arthroscopic revision of failed rotator cuff tears and demonstrated significant functional improvement in 93% of these patients, with a mean increase in the UCLA score of 15.5.(3) Some authors have also suggested proximal migration as a poor prognostic sign for rotator cuff surgery.(23, 24) Burkhart et al have demonstrated results to the contrary.(18) In their study of patients who had proximal migration of the humeral head associated with anterosuperior cuff tears (subscapularis plus supraspinatus +/- infraspinatus), 80% of the patients demonstrated lasting reversal of the superior humeral head migration and a return of overhead function after repair. Proximal migration of the humeral head is not a contraindication to rotator cuff repair. Instead, one could argue that patients with proximal migration of the humeral head have the most to gain from rotator cuff repair. It is important to note, however, in the senior author s experience, proximal migration of the humerus combined with radiographic findings of a rounded greater tuberosity and acetabularization of the proximal humerus suggests a tear that is long

12 standing and may be irreparable. In these situations, arthroscopic surgery may have limited applications. TREATMENT OPTIONS CONSERVATIVE Non-operative treatment for massive rotator cuff tears includes lifestyle changes, exercise programs and steroid injections. These methods are preferred in dealing with elderly low-demand patients with massive rotator cuff tears before consideration of surgery. As these patients are often quite disabled at the time of their initial office visit, the temptation is to rush into surgical management. This can be a mistake. These patients should initially undergo non-operative treatment with an exercise program. If the primary complaint includes pain, then a series of steroid injections may dramatically benefit the patient. The senior author prefers a series of three monthly injections to control the inflammation and then limit the injections to once yearly. After these nonoperative measures have been used, a decision regarding surgical management can be considered. The surgeon may accelerate the surgical timetable somewhat if the involved extremity is on the patients dominant arm, if the patient is extremely disabled by his or her condition, and if the patient is physiologically younger than his or her age. ARTHROSCOPIC TECHNIQUE The surgeon should begin every shoulder surgery with an examination under anesthesia. In the case of massive rotator cuff tears, one should pay particular attention to the amount of passive external rotation of the affected shoulder. If the patient

13 demonstrates an increased arc of passive external rotation in the operative shoulder, this may be suggestive of a complete or near complete tear of the subscapularis tendon. After induction of general anesthesia, the patient is placed in the lateral decubitus position. Five to 10 lbs of balanced suspension is used with the arm in 20 to 30 degrees of abduction and 20 degrees of forward flexion. Diagnostic glenohumeral arthroscopy is then performed. One should consider placing the posterior portal more inferiorly than is often used, as significant fluid extravasation can be expected. As the shoulder swells, if the posterior portal is too high, the posterior acromion can prevent a direct parallel approach into the subacromial space. The arthroscopic examination should begin with the anterior structures. A 30 degree arthroscope is used and the biceps tendon, anterior labrum, glenohumeral ligaments and subscapularis tendons are examined. Particular attention must be paid to the insertion of the subscapularis tendon and the medial sling of the biceps. The junction of the medial sling with the superior border of the subscapularis tendon make up what has been called the comma sign. (25) (Fig. 8) [Pearl #1] The 70 degree arthroscope can provide a much improved view of the subscapularis footprint when evaluating for a tear. At this point, the 70 degree arthroscope should be inserted to provide an aerial view of the subscapularis insertion as well as the medial sling of the biceps tendon. To better visualize the subscapularis footprint, the assistant can hold the arm in internal rotation and perform a posterior lever push.(26) (figure 5-26) The relationship between the anterior surface of the subscapularis and the biceps tendon is extremely important. At no time during rotation of the humerus should the biceps cut posterior to the plane of the

14 subscapularis. If this occurs, it is suggestive of an incompetent medial sling of the biceps and early biceps tendon instability. This will require a biceps tenotomy or tenodesis. The order of repair in dealing with massive cuff tears is important. If the surgeon identifies any operative biceps or subscapularis pathology, these problems must be addressed prior to any other procedures. This is because the anterior procedures become much more difficult when the shoulder becomes distended by fluid extravasation. [Pearl #2] Once a tear is confirmed, the subscapularis should be the first pathology to be repaired. Next, it is important to determine the space available for the subscapularis. The phenomenon of the roller-wringer effect has been previously described, and subcoracoid impingement is important to diagnose and treat appropriately.(27) The best portal for approaching the subscapularis and coracoid is an anterosuperolateral portal, adjacent to the anterolateral corner of the acromion. The coracoid tip should be identified. If the subscapularis is not retracted, the tip of the coracoid should be at the superior border of the subscapularis. The surgeon should make a window in the rotator interval to identify the coracoid tip and determine whether there is subcoracoid stenosis. If the distance from the coracoid tip to the anterior aspect of the subscapularis is less than 7 mm, an arthroscopic coracoplasty is necessary. The posterolateral aspect of the coracoid can be skeletonized with a combination of the shaver and electrocautery through the anterosuperolateral portal. (Fig. 9) In exposing the coracoid, one must preserve the attachment of the conjoined tendon. The plane of the coracoplasty is parallel to the plane of the subscapularis tendon. The goal is to create a 7 8 mm space between the reconfigured coracoid tip and the anterior plane of the subscapularis tendon. The 30

15 degree arthroscope should be used initially to be sure one does not get disoriented and wander inferior to the coracoid. After appropriate treatment of any intra-articular pathology, the arthroscope is placed into the subacromial space through the same posterior skin incision. A lateral portal is created in line with the posterior aspect of the clavicle or slightly anterior or posterior depending on the position of the rotator cuff tear. [Pearl #3] A complete subacromial bursectomy should be performed to best visualize and recognize the rotator cuff tear pattern. To allow complete visualization and classification of the rotator cuff tear, all fibrofatty and bursal tissue must be removed from the margins of the tear. The tear is then identified and assessed for mobility. For tear pattern recognition, it is helpful to expose the scapular spine as it serves as a landmark to separate the supraspinatus tendon anteriorly and the infraspinatus located posteriorly. (Fig. 10) Then, with the arthroscope posterior, the medial to lateral mobility of the tear can be assessed using a soft tissue grasper introduced through the lateral portal. Noncontracted crescent-shaped tears have excellent medial to lateral mobility and reduce easily to the bone bed. These tears are repaired directly to bone. Tears with poor medial to lateral mobility are then further assessed for anterior and posterior mobility with the arthroscope in the lateral position. Posterior leaf mobility is assessed by pulling the leaf anteriorly with the grasper placed through the anterior portal; the anterior leaf is assessed by pulling the anterior leaf posteriorly with the grasper placed through the posterior portal. If the anterior and posterior leaves are mobile enough to allow side-to-side closure, then the tear is classified

16 as a U-shaped massive tear, and the technique of margin convergence is used. The converged rotator cuff margin is then repaired to bone as described below. [Pearl #4] Expose the scapular spine. The muscle anterior to the spine is the supraspinatus and the one posterior to the scapular spine is the infraspinatus. U-Shaped Tears Repair of massive U-shaped tears can be gratifying, because many of these tears appear irreparable on first view. U-shaped tears demonstrate significant mobility from an anterior to posterior direction and should be initially repaired in a side-to-side fashion using the biomechanical principle of margin convergence (discussed below). One or two side-to-side sutures often will achieve such dramatic margin convergence that repair to bone can be simple.(fig. 5) We typically begin side-to-side closure with a combination of the Penetrator and BirdBeak suture passers (Arthrex) that are used to pass sutures through the posterior and anterior leaves of the cuff tear, while he views with the arthroscope in a lateral subacromial position. Most of the large and massive tears require three to four side-to-side sutures. These sutures are tied sequentially, the most medial suture first, to achieve margin convergence of the cuff margin over the prepared bone bed. Two suture anchors are then placed, one for each leaf of the cuff tear. The anchor for the posterior leaf is placed approximately 1 cm anterolateral to the edge of the posterior leaf of the cuff so that the posterior leaf can be shifted proximally and anteriorly. This maneuver maximizes the moment produced by the posterior cuff in the transverse and coronal planes, thereby creating balanced force couples in both planes. The achievement of

17 balanced force couples allow the shoulder to establish a stable fulcrum of glenohumeral motion. The anterior leaf typically is not as mobile as the posterior leaf in a U-shaped tear, and a significant shift of the anterior leaf usually is not possible or necessary, so the anterior anchor is placed adjacent to the edge of the anterior leaf. The sutures from the anchor are then passed through the tissue and tied. The free margin of the rotator cuff can then be easily repaired to the bone bed in a tension-free manner. The technique of margin convergence both allows repair of seemingly irreparable tears and minimizes strain at the repair site.(28) Theoretically, this decreases the risk of rupture and subsequent failure of the rotator cuff repair. L-Shaped Tears In L-shaped and reverse-l-shaped tears, one of the leaves is more mobile than the other leaf and can be easily brought to the bone bed and to the other leaf. In these cases, side-to-side suturing is first performed along the longitudinal split and then the converged margin is repaired to bone. (Fig. 6) In more chronic cases, the physiologic pull of the rotator muscle posteriorly will cause a reversed L-shaped tear to assume a more U-shaped configuration. Preparation of the bone bed The bone bed must be meticulously prepared down to a bleeding base. Without this, good rotator cuff healing cannot occur. We use the electrocautery to remove the soft tissue from the tuberosity and then uses a high speed burr to shave the bone to a bleeding base. A ring curette is used to smooth the articular margin.

18 [Pearl #5] Meticulously prepare the rotator cuff footprint to a bleeding base. This allows to maximum healing. SPECIFIC TECHNIQUES A category of great interest is that of the immobile contracted rotator cuff tear. These are rotator cuff tears in which the tear margins will not reach the bone bed by standard repair and mobilization techniques. In the past, when such tears were encountered, only rudimentary mobilization techniques were available and frequently partial repairs were all that could be performed. With recent advances in arthroscopic shoulder surgery, we now have multiple tools in our arsenal to tackle these difficult tears. We will discuss some of them below. EXCAVATION OF THE ROTATOR CUFF In massive rotator cuff tears, the cuff is often scarred to the deltoid and the acromion. In such cases, one must excavate the cuff from the bone and soft tissue to which it has scarred. Identifying the fat pad posterior to the AC joint and then developing the fatty layer between the rotator cuff below and the acromion above is the best way to achieve this goal. (Fig. 11) One then proceeds laterally until the rotator cuff margin is found. In performing this dissection, we commonly view through a lateral portal and introduce our instruments through a posterior portal. By staying in the fatty layer, one can be sure to stay above any viable rotator cuff tissue. It is helpful to identify the spine of the scapula prior to doing this, to delineate the border between the supraspinatus and infraspinatus. The skeletonized spine of the scapula looks much like

19 the keel of a boat. The tissue anterior to the keel is the supraspinatus, while the tissue posterior is the infraspinatus. [Pitfall #1] Do not accidentally debride viable rotator cuff tissue. Excavate the cuff. It is also important to debride the synovialized bursal leaders that are frequently present in chronic rotator cuff tears. Such bursal leaders connect the tendon margin to the deltoid fascia laterally and can be confused with tendon. A good way to distinguish tendon from bursa is to remember that the bursal leader inserts into the deltoid fascia while tendon inserts into the bone. These bursal leaders must be appropriately debrided. Once the tendon margins are properly identified the appropriate repair can be performed. [Pearl #6] Rotator cuff tendon inserts into bone. Bursa inserts into the fascia. MARGIN CONVERGENCE This term refers to the phenomenon that occurs with side-to-side closure of large rotator cuff tears, in which the free margin of the tear converges toward the greater tuberosity as side-to-side repair progresses. (Fig. 5) This technique reduces the strain at the free edge of the cuff dramatically, leaving a virtually tension-free converged cuff margin overlying the humeral bone bed for repair. For example, side-to-side closure of 2/3 of a U-shaped tear will reduce the strain at the cuff margin to 1/6 the strain that existed at the preconverged cuff margin. This mechanical strain reduction creates an added safety factor for the repair of tendon to bone because decreased strain means that there will be a lower likelihood of failure of fixation to bone. Strain reduction should

20 also be effective in protecting against suture failure as well as propagation of the tear even if the cuff margin is not repaired to bone. It is possible that the reduced strain can enhance function indirectly by decreased mechanical stimulation of pain receptors in the rotator cuff, because deformation of these receptors should decrease as the strain decreases. Margin Convergence is a powerful tool in the surgeon s armamentarium in repairing massive rotator cuff tears. INTERVAL SLIDES Rarely, massive rotator cuff tears may be fixed and severely contracted, with poor mobility from a medial to lateral and an anterior to posterior direction. This lack of mobility precludes either a repair directly to bone (as in crescent-shaped tears) or after margin convergence (as in U-shaped tears or L-shaped tears). In these cases, an interval slide technique may be used to mobilize tendons. In the orthopedic literature, Bigliani and Flatow introduced the utility of the open interval slide.(29, 30) Cordasco and Bigliani described the open anterior interval slide, whereas Codd and Flatow suggested an open posterior interval slide as well. Tauro was the first to describe an arthroscopic interval slide for release of the rotator interval from the supraspinatus tendon.(31) He used an arthroscopic adaptation of the Bigliani technique to release the coracohumeral ligament and contracted immobile adhesed tears. His technique involved arthroscopic division of the rotator interval just anterior to the leading edge of the supraspinatus tendon. The line of this cut went just above the root of the biceps and aimed toward the base of the coracoid. This release improved the mobility of the supraspinatus, allowing repair of retracted tears.

21 [Pearl #7] The double interval slide can give you 3-5 cm of additional medial to lateral tendon excursion in severely contracted rotator cuff tears. Our procedure for the anterior interval slide is similar to the release of the subscapularis. The base of the coracoid is skeletonized and in so doing, adhesions securing the anterior edge of the supraspinatus to the coracoid are released. The supraspinatus tendon is then identified, and a traction stitch is placed at the anterolateral corner of the tendon and pulled out through a lateral portal. When performing an anterior interval slide, it is easiest to view from the lateral or posterior subacromial portal. These portals allow the correct orientation and visualization of the release. A dissecting scissor is introduced and the supraspinatus tendon is then released from lateral to medial, starting at the free margin of the tendon tear and progressing to the base of the coracoid. This release also incises the coracohumeral ligament. (Fig. 12) Alternatively, an anterior interval slide in-continuity can be done by bluntly releasing the coracohumeral ligament from the coracoid base.(32) In general, with an isolated anterior interval slide, only 1 to 2 cm of lateral excursion of the supraspinatus is gained. With massive adhesed retracted tears, this is often not enough lateral excursion to allow apposition of the tendon to its bone bed. In this case, the addition of a second, more posteriorly located interval slide is necessary. When done in combination, the procedure is known as a double interval slide. (21) The posterior interval slide releases the interval between the supraspinatus and the infraspinatus. (Fig. 13) Arthroscopically exposing the scapular spine, which marks the interval between the supraspinatus and infraspinatus tendon, is imperative. This can be done by resecting the medial fibrofatty tissue until the arching column of the scapular

22 spine is visible. Traction sutures are then placed on the supraspinatus and infraspinatus tendons. The posterior release is performed by cutting between the supraspinatus and infraspinatus tendons with an arthroscopic scissor, aiming toward the base of the scapular spine. (Fig. 14) Care must be taken to protect the suprascapular nerve as it curves around the base of the scapular spine. To help protect the nerve, the supraspinatus and infraspinatus should be pulled laterally while the surgeon releases the interval. This pulls the tendon away from the nerve to decrease the chance of damage while cutting the interval. Also, the blades of the scissors should be raised above the level of the posterior-superior glenoid neck in order not to entrap the nerve at the base of the scapular spine in the event that one inadvertently slips medially with the scissors. This allows a safe release of the posterior interval. The release is terminated once the fat pad is reached. By doing the double interval slide, 3 to 5 cm of additional lateral excursion of the supraspinatus and infraspinatus can be attained. This generally allows the tendon to be repaired directly to the bone bed on the humeral neck and greater tuberosity. Furthermore, the portion of the infraspinatus that is released gains a similar amount of lateral mobility. Because these 2 tendon flaps are quite floppy and difficult to control, we repair them to bone prior to placing side-to-side sutures. FOOTPRINT RECONSTRUCTION The rotator cuff footprint is a complex three-dimensional structure overlying a large surface of the proximal humerus. One potential shortcoming of suture anchor repair of the rotator cuff is that suture anchors provide point fixation only. Therefore, when

23 performing an arthroscopic rotator cuff repair with a single-row of lateral anchors, the normal footprint of the rotator cuff is not restored and the medial aspect of the rotator cuff tendon insertion can lift away from the bone bed during abduction of the shoulder. A double-row repair using a row of medial anchors at the articular margin and a row of lateral anchors more adequately restores the footprint of the rotator cuff and increases the area of contact for healing. Furthermore, by providing a second row of fixation, the number of points of fixation is increased, thereby increasing the strength of the initial repair construct and decreasing the load each anchor must resist. All these factors can potentially improve the mechanical strength and function of the repaired rotator cuff by providing more complete healing across the anatomic footprint.(33) Cadaveric studies have highlighted the superiority of a double-row repair at restoring the supraspinatus footprint compared with a single-row repair.(37-39) In our experience, a single lateral row reconstituted 47% of the footprint in 26 patients whereas the doublerow repair reconstituted the remaining 53% in these patients.(34) Today, in addition to the double-row, we now have transosseous equivalent or suture bridge techniques in which compression is applied to the tendon against the prepared bone bed. (Fig. 15) In this technique, two rows of fixation with sutures from the medial row draping over the tendon laterally provide increased tendon contact and compression over the anatomic footprint to improve and promote healing.(35, 36) Utilizing this technique, Frank et al. demonstrated a high healing rate on imaging studies at one year. Of the first 25 patients repaired with the technique, 88% had an intact rotator cuff repair on MRI evaluation.(37) This indicates excellent cuff healing, as judged by the intact repair sites, compared with most standard arthroscopic rotator cuff repair series.

24 Although this is a small sample size, continuing advancements in arthroscopic rotator cuff repair holds a lot of promise for the future. SUBSCAPULARIS MOBILIZATION AND REPAIR When there is a complete tear of the subscapularis with retraction, finding the retracted subscapularis tendon can be difficult. The key to finding the subscapularis and differentiating it from the conjoined tendon and the coracoacromial ligament is to locate the comma sign. (25) (Fig. 8) The comma sign is a comma shaped arc of tissue located at the superolateral border of the subscapularis, which always will lead the surgeon to the superolateral border of the subscapularis. The comma is actually the remnant of the medial sling of the biceps and is composed of fibers of the medial head of the coracohumeral ligament as well as a portion of the superior glenohumeral ligament. Typically, when the subscapularis fails completely, the medial sling of the biceps will pull away from the lesser tuberosity, so that it remains confluent with the superolateral subscapularis tendon. This is convenient because the comma then allows the surgeon to be able to fully delineate the superolateral aspect of the subscapularis. If the biceps is intact, visualization will be much easier if one does a biceps tenotomy (in preparation for later tenodesis) prior to repairing the subscapularis. We generally prefer to do a biceps tenodesis except in elderly patients who have low demands. In these patients, we perform a simple tenotomy. Initially, two half- racking sutures are placed through the biceps tendon and the tendon is detached from the superior labrum with arthroscopic scissors. (Fig. 16) The tendon is then exteriorized through the anterosuperolateral portal and a whipstitch is

25 placed in the tendon. (Fig. 17) The biceps tendon is then allowed to retract down the bicipital groove prior to performing a tenodesis with a BioTenodesis interference screw (Arthrex, Inc, Naples, FL) after the subscapularis repair. One must recognize that biceps tenotomy or tenodesis is important in the case of biceps subluxation or dislocation. If the biceps is not transferred out of the way of the subscapularis to a tenodesis site, the persistent force of the subluxed biceps over the top of the subscapularis repair will cause the repair to fail. In mobilizing a retracted subscapularis, one must become comfortable dissecting around the coracoid. Remember that the posterolateral aspect of the coracoid is at least 15 mm away from all neurovascular structures.(38) First, a traction suture is placed at the junction between the comma tissue and the upper border of the subscapularis. Using the traction suture and pulling this suture through the anterosuperolateral portal makes the subscapularis release much easier since it gives a counterforce for the dissecting instruments (scissors, elevator) to work against. In the case of a complete tear, the subscapularis will retract considerably, often to the level of the anterior labrum medially. For a retracted subscapularis, a 3-sided release (anterior, superior and posterior) is necessary, using a combination of a shaver and electrocautery to release the tendon from the coracoid neck and base. (Fig. 18) We also use an arthroscopic elevator to release adhesions from the arch of the coracoid neck and anterior glenoid neck. In performing the release, one should be careful not to plunge inferomedial when working around the base of the coracoid. The anterior release is achieved by dissecting the subscapularis from the coracoid. In doing this, the posterolateral aspect of the coracoid is essentially skeletonized,

26 exposing the neck and the base of the coracoid. Then, a superior release is done by using an elevator to release any adhesions between the upper subscapularis and the lateral arch of the coracoid base and coracoid neck. Finally, the posterior release from the glenoid neck is done using an elevator. At this point, the subscapularis tendon should have enough additional lateral excursion to allow the surgeon to make a window in the rotator interval to visualize the tip of the coracoid all the way to the base. In doing this, the attachment of the coracohumeral ligament to the coracoid is completely released, allowing maximal lateral excursion of the subscapularis and also achieving an anterior interval slide incontinuity which gives added lateral excursion to the supraspinatus. In some cases of chronic tears, these mobilization techniques may not bring the subscapularis tendon as far laterally as desired to obtain a good footprint on the lesser tuberosity. In such a case, the surgeon should consider medialization of the bone bed up to 5 mm for creation of a larger footprint. This degree of medialization of the footprint has not caused any loss of function in our experience. It is better to have a larger footprint by medializing the lesser tuberosity than to risk disruption of the repair by over tensioning. In repairing the subscapularis, it is optimal to use one anchor per linear centimeter of detachment. In anatomic dissections, we have found that the superior-inferior length of the footprint of the normal subscapularis is 2.5 cm.(39) Therefore, for a 50% tear, one anchor should be should be sufficient and for a 100% tear, two or three anchors are optimal.

27 Anchors are placed through an accessory anterior portal to obtain an appropriate angle of approach to the lesser tuberosity. Once the anchors are placed, sutures are passed through the superolateral border of the subscapularis tendon using a Viper suture passer (Arthrex, Inc, Naples, FL) and tied down through the anterosuperolateral portal. (Fig. 19) We prefer using static knots here, rather than sliding knots because the acute angle makes the use of sliding knots difficult. PARTIAL ROTATOR CUFF REPAIR: Balancing the force couples. In situations where a massive, contracted immobile rotator cuff tear is not completely repairable despite the application of all available tools, partial rotator cuff repair is a valid option. Partial repair respects and restores the biomechanical function of the rotator cuff. The goal of partial repair is to achieve sufficient tendon healing to regain overhead function. To accomplish this, the rotator cuff repair must satisfy the following five biomechanical criteria. 1. Force couples must be balanced in the coronal and transverse planes. 2. A stable fulcrum kinematic pattern must be reestablished. 3. The shoulder s suspension bridge must be reestablished. 4. The residual defect must occupy a minimal surface area. 5. The residual defect must possess edge stability.(40, 41) These five criteria are primarily achieved by balancing the force couple between the anterior and posterior portions of the shoulder. This balance requires an intact subscapularis tendon anteriorly, and an intact inferior half of the infraspinatus tendon posteriorly. Anatomically, this requisite configuration corresponds to the anterior and posterior attachments of the rotator cable. Thus, during arthroscopic surgery, the major

28 goal of partial rotator cuff repair is to mobilize and repair the rotator cuff to reestablish these cable attachments. It should be emphasized, however, that complete anatomic closure and healing of the rotator cuff still achieves superior and more predictable functional results when compared with partial closure or partial healing of the rotator cuff with a persistent defect. COMPLICATIONS AND TECHNICAL PITFALLS Obviously, when dealing with a retracted, immobile, massive rotator cuff tear, the risk of intraoperative and postoperative complications escalates. Many of these complications can be minimized with meticulous surgical technique. First and foremost, the surgeon should understand the complexity and difficulty of these cases. They can easily take 2 to 3 hours to complete even in the hands of an experienced arthroscopic shoulder surgeon. The first difficulty the surgeon may encounter is the increased fluid extravasation that often occurs. Since the rotator cuff and capsule are incompetent, intra-articular fluid can easily extravasate. The resultant swelling can pose a significant problem when performing a repair on a torn subscapularis. For this reason, as soon as a subscapularis tear is identified, it is important to proceed directly to repair of the torn subscapularis and coracoplasty, if indicated. When mobilizing a massive retracted tear of the supraspinatus and infraspinatus, the surgeon must respect the anatomy of the suprascapular nerve to avoid injury to this structure during the interval slide technique.

29 A less serious problem when performing the arthroscopic repair is passing sutures in floppy cuff tissue. Once the cuff is well mobilized, the surgeon must pass the sutures from the bone anchors through the cuff tissue. There are many techniques to perform this step. We use the Scorpion suture passer (Arthrex, Naples, FL) for antegrade suture passage in floppy tendon tissue. Retrograde suture passage is also frequently utilized, maintaining tissue tension by pulling on the traction sutures while the retrograde passer penetrates the tendon. POST-OPERATIVE REHABILITATION PROTOCOL After repair of a massive rotator cuff tear, with or without associated repair of the subscapularis, the patient is placed in a sling for 6 weeks and only elbow motion is allowed. No overhead motion is allowed for the first 6 weeks. The patient may use the hand in the straight ahead position for writing or for eating. The sling can be removed daily for showering. At 6 weeks post-op, the sling is discontinued. From the 7 th to 16 th postoperative weeks, the patient begins a stretching program geared toward gaining external rotation and overhead motion. If the subscapularis has been repaired, external rotation is limited to 45 degrees. If the subscapularis was not involved, the patient may perform passive external rotation stretches as tolerated. No active motion is allowed during this time. At 17 weeks post-op, strengthening is begun, first with Thera-Band elastic resistive bands followed by light weights as dictated by the patient s progress. Unrestricted activities are delayed until12 months post-op for patients with massive rotator cuff repairs.

30 REFERENCES 1. DeOrio JK, Cofield RH. Results of a second attempt at surgical repair of a failed initial rotator-cuff repair. J Bone Joint Surg Am Apr;66(4): Burkhart SS, Danaceau SM, Pearce CE, Jr. Arthroscopic rotator cuff repair: Analysis of results by tear size and by repair technique-margin convergence versus direct tendon-to-bone repair. Arthroscopy Nov-Dec;17(9): Lo IK, Burkhart SS. Arthroscopic revision of failed rotator cuff repairs: technique and results. Arthroscopy Mar;20(3): Rockwood CA, Jr., Williams GR, Jr., Burkhead WZ, Jr. Debridement of degenerative, irreparable lesions of the rotator cuff. J Bone Joint Surg Am Jun;77(6): Burkhart SS. Arthroscopic treatment of massive rotator cuff tears. Clin Orthop Relat Res Sep(390): Burkhart SS. Arthroscopic treatment of massive rotator cuff tears. Clinical results and biomechanical rationale. Clin Orthop Relat Res Jun(267): Gerber C, Meyer DC, Schneeberger AG, Hoppeler H, von Rechenberg B. Effect of tendon release and delayed repair on the structure of the muscles of the rotator cuff: an experimental study in sheep. J Bone Joint Surg Am Sep;86-A(9): Greiner A, Golser K, Wambacher M, Kralinger F, Sperner G. The course of the suprascapular nerve in the supraspinatus fossa and its vulnerability in muscle advancement. J Shoulder Elbow Surg May-Jun;12(3):256-9.

31 9. Djurasovic M, Marra G, Arroyo JS, Pollock RG, Flatow EL, Bigliani LU. Revision rotator cuff repair: factors influencing results. J Bone Joint Surg Am Dec;83-A(12): Bigliani LU, Cordasco FA, McIlveen SJ, Musso ES. Operative treatment of failed repairs of the rotator cuff. J Bone Joint Surg Am Dec;74(10): Galatz LM, Ball CM, Teefey SA, Middleton WD, Yamaguchi K. The outcome and repair integrity of completely arthroscopically repaired large and massive rotator cuff tears. J Bone Joint Surg Am Feb;86-A(2): Dejardin LM, Arnoczky SP, Ewers BJ, Haut RC, Clarke RB. Tissue-engineered rotator cuff tendon using porcine small intestine submucosa. Histologic and mechanical evaluation in dogs. Am J Sports Med Mar-Apr;29(2): Burkhart SS, Barth JR, Richards DP, Zlatkin MB, Larsen M. Arthroscopic repair of massive rotator cuff tears with stage 3 and 4 fatty degeneration. Arthroscopy Apr;23(4): Inman V, Saunder J, Abbott L. Observations on the function of the shoulder. J Bone Joint Surg Am. 1944;26: Burkhart SS, Esch JC, Jolson RS. The rotator crescent and rotator cable: an anatomic description of the shoulder's "suspension bridge". Arthroscopy. 1993;9(6): Halder AM, O'Driscoll SW, Heers G, Mura N, Zobitz ME, An KN, et al. Biomechanical comparison of effects of supraspinatus tendon detachments, tendon defects, and muscle retractions. J Bone Joint Surg Am May;84-A(5): Cofield RH. Subscapular muscle transposition for repair of chronic rotator cuff tears. Surg Gynecol Obstet May;154(5):

32 18. Burkhart SS, Tehrany AM. Arthroscopic subscapularis tendon repair: Technique and preliminary results. Arthroscopy May-Jun;18(5): Barth JR, Burkhart SS, De Beer JF. The bear-hug test: a new and sensitive test for diagnosing a subscapularis tear. Arthroscopy Oct;22(10): Burkhart SS, Lo IK, Brady PC. Burkhart's View of the Shoulder: A Cowboy's Guide to Advanced Shoulder Arthroscopy. Lippincott Williams & Wilkins Lo IK, Burkhart SS. Arthroscopic repair of massive, contracted, immobile rotator cuff tears using single and double interval slides: technique and preliminary results. Arthroscopy Jan;20(1): Neviaser RJ. Evaluation and management of failed rotator cuff repairs. Orthop Clin North Am Apr;28(2): Klinger HM, Steckel H, Ernstberger T, Baums MH. Arthroscopic debridement of massive rotator cuff tears: negative prognostic factors. Arch Orthop Trauma Surg May;125(4): Vandenbussche E, Bensaida M, Mutschler C, Dart T, Augereau B. Massive tears of the rotator cuff treated with a deltoid flap. Int Orthop Aug;28(4): Lo IK, Burkhart SS. The comma sign: An arthroscopic guide to the torn subscapularis tendon. Arthroscopy Mar;19(3): Adams CR, Schoolfield JD, Burkhart SS. The results of arthroscopic subscapularis tendon repairs. Arthroscopy Dec;24(12): Lo IK, Burkhart SS. The etiology and assessment of subscapularis tendon tears: a case for subcoracoid impingement, the roller-wringer effect, and TUFF lesions of the subscapularis. Arthroscopy Dec;19(10):

33 28. Burkhart SS, Athanasiou KA, Wirth MA. Margin convergence: a method of reducing strain in massive rotator cuff tears. Arthroscopy Jun;12(3): Cordasco FA, Bigliani LU. The rotator cuff. Large and massive tears. Technique of open repair. Orthop Clin North Am Apr;28(2): Codd T, Flatow EL. Anterior acromioplasty, tendon mobilization, and direct repair of massive rotator cuff tears. In: Burkhead WZ Jr, ed. Rotator Cuff Disorders. Baltimore: Williams and Wilkins. 1996: Tauro JC. Arthroscopic "interval slide" in the repair of large rotator cuff tears. Arthroscopy Jul-Aug;15(5): Lo IK, Burkhart SS. The interval slide in continuity: a method of mobilizing the anterosuperior rotator cuff without disrupting the tear margins. Arthroscopy Apr;20(4): Lo IK, Burkhart SS. Double-row arthroscopic rotator cuff repair: re-establishing the footprint of the rotator cuff. Arthroscopy Nov;19(9): Brady PC, Arrigoni P, Burkhart SS. Evaluation of residual rotator cuff defects after in vivo single- versus double-row rotator cuff repairs. Arthroscopy Oct;22(10): Park MC, Cadet ER, Levine WN, Bigliani LU, Ahmad CS. Tendon-to-bone pressure distributions at a repaired rotator cuff footprint using transosseous suture and suture anchor fixation techniques. Am J Sports Med Aug;33(8): Sugaya H, Maeda K, Matsuki K, Moriishi J. Repair integrity and functional outcome after arthroscopic double-row rotator cuff repair. A prospective outcome study. J Bone Joint Surg Am May;89(5):

34 37. Frank JB, ElAttrache NS, Dines JS, Blackburn A, Crues J, Tibone JE. Repair site integrity after arthroscopic transosseous-equivalent suture-bridge rotator cuff repair. Am J Sports Med Aug;36(8): Lo IK, Lind CC, Burkhart SS. Glenohumeral arthroscopy portals established using an outside-in technique: neurovascular anatomy at risk. Arthroscopy Jul;20(6): Richards DP, Burkhart SS, Tehrany AM, Wirth MA. The subscapularis footprint: an anatomic description of its insertion site. Arthroscopy Mar;23(3): Burkhart SS. Partial repair of massive rotator cuff tears: the evolution of a concept. Orthop Clin North Am Jan;28(1): Burkhart SS, Nottage WM, Ogilvie-Harris DJ, Kohn HS, Pachelli A. Partial repair of irreparable rotator cuff tears. Arthroscopy Aug;10(4):

35 SUGGESTED READING 1. Burkhart s View of the Shoulder: A Cowboy s Guide to Advanced Shoulder Arthroscopy. - A comprehensive review of advanced shoulder arthroscopic concepts and technique. Step by step details on procedures including repairing massive rotator cuff tears are outlined. 2. Burkhart SS, Lo IK. Arthroscopic rotator cuff repair. J Am Acad Orthop Surg. 2006; 14(6): Good review article for understanding the fundamentals of rotator cuff repair. 3. Lo IK, Burkhart SS. Double-row arthroscopic rotator cuff repair: re-establishing the footprint of the rotator cuff. Arthroscopy. 2003;19(9): Provides information on the concept and biomechanical principles of the double-row rotator cuff repair technique. 4. Frank, J.B., et al., Repair site integrity after arthroscopic transosseous-equivalent suture-bridge rotator cuff repair. Am J Sports Med, (8): p An interested article on the outcomes following transosseous equivalent rotator cuff repair. 5. Lo IK, Burkhart SS. The interval slide in continuity: a method of mobilizing the anterosuperior rotator cuff without disrupting the tear margins. Arthroscopy Apr;20(4): A technical note on the interval slide technique.

36 Figure Legend Figure 1 Coronal plane force couple. The inferior rotator cuff must balance the moment created by the deltoid. C (rotator cuff force); D (deltoid force); O (center of rotation); a (moment arm of the inferior rotator cuff); A (moment arm of the deltoid) Figure 2 Transverse plane force couple (axillary view). The anterior rotator cuff must balance the moment created by the posterior rotator cuff. I (infraspinatus); S (subscapularis); O (center of rotation); r (moment arm of the subscapularis); R (moment arm of the infraspinatus and teres minor)

37 Figure 3 The rotator cable and crescent. A) superior view B) Posterior view. The rotator cable spans the entire length of the supraspinatus and infraspinatus insertions. C (rotator cable width); B (rotator crescent); I (infraspinatus); S (supraspinatus); TM (teres minor); BT (biceps tendon) Figure 4 Crescent-shaped tear A) superior view B) these tears demonstrate excellent mediolateral mobility and can be repaired directly to bone. I (infraspinatus); S (supraspinatus)

38 Figure 5 U-shaped tear A) superior view B) these tears demonstrate excellent anteroposterior mobility. They should be repaired with side-to-side margin convergence sutures first. C) They can then be repaired directly to bone. I (infraspinatus); S (supraspinatus) Figure 6 Chronic L-shaped tear A) superior view B) these tears demonstrate excellent anteroposterior mobility. Margin convergence sutures should restore the anterolateral corner of the supraspinatus (A ) to its anatomical insertion point (A) first. C) It can then be repaired directly to bone in a tension-free manner. I (infraspinatus); S

39 (supraspinatus); Sub (subscapularis); RI (rotator interval); CHL (coracohumeral ligament) Figure 7 The bear hug test. The extended hand of the affected shoulder is placed on the opposite shoulder as the patient resists the examiners force to pull the hand off the shoulder. The test is positive if the examiner is able to lift the hand off the shoulder.

40 Figure 8 The comma tissue. The comma is always located just lateral to the upper border of the subscapularis tendon (SSc). coracoid tip (CT) Figure 9 Posterior viewing portal of right shoulder (70 degree scope). The coracoid neck (CN) and the coracoid tip (CT) are visible. subscapularis tendon (SSc). Figure 10 Lateral viewing portal of left shoulder. The scapular spine (SP) separates the infraspinatus (IS) from the supraspinatus (SS)

41 Figure 11 Lateral viewing portal of right shoulder. A) The fibrofatty layer is initially identified above the rotator cuff just posterior to the acromioclavicular joint. B) The layer is developed to identify the rotator cuff. Bursal tissues insert into the deltoid muscle fascia while the rotator cuff tendon inserts into the bone. G (glenoid); RC (rotator cuff); AC (acromion); H (humerus); B (bursal leader) Figure 12 Massive, contracted, immobile tear A) superior view; the anterior interval slide incises the interval between the supraspinatus (SS) tendon and the rotator

42 interval B) The slide gives an additional 1 2 cm of lateral excursion C) The residual defect is closed by side-to-side sutures between the infraspinatus and supraspinatus, and then the distal ends of these two tendons are repaired to bone. IS (infraspinatus); Sub (supraspinatus); Sub (subscapularis); RI (rotator interval); CHL (coracohumeral ligament) Figure 13 Massive, contracted, immobile tear A) superior view; the double interval slide involves an anterior interval slide between the supraspinatus (SS) tendon and the rotator interval and a posterior interval slide, between the supraspinatus (SS) and the infraspinatus (IS) B) The anterior slide gives an additional 1 2 cm of lateral excursion

43 while the posterior slide gives up to 3-5 cm of excursion C) The tendons can then be repaired to the lateral bone bed D) The residual defect between the tendons (SS and IS) is closed by side-to-side sutures. Sub (supraspinatus); Sub (subscapularis); RI (rotator interval); CHL (coracohumeral ligament) Figure 14 Posterior interval slide. While aiming toward the scapular spine, the arthroscopic scissors cut between the tendons of the infraspinatus and supraspinatus. Figure 15 Subacromial view of a double-row footprint reconstruction technique.

44 Figure 16 Posterior viewing portal, left shoulder. Half-racking sutures placed in the biceps tendon. It creates a strong strangulation effect to present suture cut-out. Figure 17 The biceps is pulled out through the anterosuperolateral portal and a whipstitch placed into the tendon.

45 Figure 18 Posterior viewing portal, right shoulder (70 degree arthroscope). A 30 degree elevator is used through the anterosuperolateral portal to perform the superior release between the subscapularis (SSc) and the coracoid neck (CN) Figure 19 Posterior viewing portal, right shoulder. The sixth-finger knot pusher is used to manipulate and tie down the subscapularis (SSc) tendon into the lesser tuberosity.