Summary: Understanding the effect of superior labral

Transcription

1 Techniques in Shoulder & Elbow Surgery 2(2):74 84, Lippincott Williams & Wilkins, Inc., Philadelphia T E C H N I Q U E Dead Arm Syndrome: Torsional SLAP Lesions versus Internal Impingement STEPHEN S. BURKHART, M.D. Department of Orthopedic Surgery Baylor College of Medicine University of Texas Health Science Center, San Antonio San Antonio, Texas, U.S.A. PETER M. PARTEN, M.D. Institute for Orthopedic Research and Education San Antonio, Texas, U.S.A. Summary: Understanding the effect of superior labral lesions on the function of the shoulder is essential to successfully treating the overhead athlete. Recognizing the pseudolaxity due to SLAP lesions and the pathologic peel-back sign is critical in evaluating the injured shoulder and repairing the SLAP lesion. The mechanical characteristics of suture anchors are more favorable in resisting the pathologic forces responsible for the peelback mechanism. The higher success rate of arthroscopic suture anchor repair of SLAP lesions compared with open capsulolabral reconstruction suggests that SLAP lesions are the usual cause of the dead arm syndrome. In our experience, arthroscopic repair of SLAP lesions can return the overhead athlete to pre-operative level of function in the vast majority of cases (87% return to pre-operative level for two or more seasons). Address correspondence and reprint requests to Dr. Stephen S. Burkhart, 540 Madison Oak Drive, Suite 620, San Antonio, TX 78258, USA. HISTORICAL PERSPECTIVE The dead arm is perhaps the most feared malady among throwing athletes (1). This condition, which we define as an inability for the thrower to throw with his preinjury velocity and control because of a combination of pain and subjective unease in the shoulder, is extremely disabling and potentially career-ending to the overhead athlete. For years, physicians have been frustrated by poor results with conventional treatment in this group of athletes. In fact, as recently as the 1970s, pitchers with dead arm syndrome were often referred to psychologists and psychiatrists to discover why they didn t want to throw (Red Murff, New York Mets, 1972, personal communication). This attitude received solid support in the orthopedic literature. Rowe and Zarins (2) defined a dead arm syndrome in patients with recurrent transient anterior subluxation of the shoulder. They stated that patients with this syndrome experienced sudden pain and weakness with the arm in abduction and external rotation. Overhead athletes who developed this syndrome were unable to throw hard. Our definition of the dead arm as a pathologic shoulder condition in which throwers are unable to throw with their preinjury velocity and control is a functional description of the symptom complex described by Rowe and Zarins. Interestingly, part of the mystery and mythology of the dead arm lies in the fact that throwers often have difficulty in describing the uneasy sensations they feel as they attempt to throw a ball. They usually relate the discomfort to the late cocking phase of the throwing sequence, when the arm begins to accelerate forward. This is the same part of the pitching sequence in which the injury is sustained; pitchers feel a sudden sharp pain in late cocking, when the shoulder is maximally abducted and externally rotated, and then the arm goes dead as they try to accelerate it. This consistent history has led the senior author (S.S.B.) to conclude that this is an acceleration injury (1) rather than a deceleration injury, as previously hypothesized by Andrews et al. (3). Dr. Frank Jobe et al. (4,5) described impingementinstability overlap. They postulated that repetitive throwing gradually stretched out the anterior capsuloligamentous complex, allowing anterosuperior migration of the humeral head during throwing, thus causing subacromial impingement symptoms. They reported some success with open anterior capsulolabral reconstruction, but their numbers were small and their results far from ideal (50% returned to pitching in a report of 12 pitchers). 74 Techniques in Shoulder and Elbow Surgery

2 Dead Arm Syndrome Andrews et al. (3) first observed anterosuperior glenoid labrum tears in throwers, and their treatment was to arthroscopically debride these lesions. They postulated that this labral injury was a deceleration injury that occurred in the follow-through phase of throwing, with the biceps acting as a decelerator of the rapidly extending elbow. They theorized that this tensile force in the biceps caused a traction injury to the anterosuperior labrum by virtue of the biceps root attachment to the anterosuperior labrum. Snyder et al. (6) subsequently described SLAP (superior labrum anterior and posterior) lesions in the general population but did not specifically relate them to the overhead athlete. Dr. Christopher Jobe described posterosuperior glenohumeral impingement ( internal impingement ), whereby a portion of the rotator cuff contacts the posterosuperior glenoid and labrum when the arm is in the cocked position of abduction and external rotation (7). He credited Walch et al. (8) with initially describing this internal impingement, but he applied his observations to throwing athletes and elucidated an expanded spectrum of injury to the rotator cuff, glenoid labrum, and even bone as a result of this internal impingement. He also hypothesized that the internal impingement in throwers might progressively worsen by gradual repetitive stretching of the anterior capsuloligamentous structures. His theory of anterior microinstability aggravating internal impingement was offered as justification for using anterior capsulolabral reconstruction to treat patients with this problem, even though the results of treatment of pitchers by this procedure were unpredictable (50% return to pitching) (4). Interestingly, Christopher Jobe (7) agreed with Walch (8) that the internal impingement that they had both described was physiologic and occurred normally in every shoulder that was placed in the cocked position. Therefore, in our opinion, it is difficult to understand how this normal phenomenon could be the source of such dramatic shoulder dysfunction as one sees with the dead arm. Morgan et al. (9) reported on 53 throwing athletes with torsional type II SLAP lesions who underwent arthroscopic repair of the SLAP lesions without additional surgical treatment. These athletes had an 87% return to preinjury levels of throwing. Of the 53 baseball players, 44 were pitchers, of whom 84% returned to their preinjury level of throwing. This is by far the largest group of surgically treated pitchers in the orthopedic literature, and the results, as judged by return to preinjury levels of throwing, are much better than those of the open instability repairs. In view of the vast improvement in results with this approach to the dead arm, it is our firm belief that the torsional SLAP lesion is the most common culprit in the injured overhead athlete and that this lesion must be strongly considered in evaluating the injured throwing shoulder. PATHOLOGY AND PATHOMECHANICS The Peel-Back Sign We categorized superior labral lesions into three subtypes by anatomic location (9) (Fig. 1). In throwers with posterior SLAP lesions and those with combined anterior and posterior SLAP lesions, we have observed a dynamic torsional peel-back phenomenon (10). When the arm is removed from traction and brought into abduction and external rotation, the biceps tendon assumes a more vertical and posteriorly directed orientation. This dynamic FIG. 1. Three subtypes of type II superior labrum anterior and posterior (SLAP) lesions shown by anatomic location. A. Anterior. B. Posterior. C. Combined anteroposterior. Volume 2, Issue 2 75

3 S. S. Burkhart and P. M. Parten FIG. 2. The dynamic peel-back test. As the arm is brought from the restingposition (A) into 90 abduction and 90 external rotation (B), the biceps/superior labral complex is observed to drop medially over the edge of the glenoid, confirming a posterior torsional SLAP lesion. angle change produces a twist at the base of the biceps, which then transmits a torsional force to the posterosuperior labrum, causing it to rotate medially over the corner of the glenoid onto the posterosuperior scapular neck. We call this phenomenon the peel-back sign (Fig. 2). This is a consistent arthroscopic finding in patients with posterior SLAP lesions and those with combined anteroposterior SLAP lesions, and it is absent in normal shoulders. Furthermore, the dynamic peel-back sign is eliminated by repair of the SLAP lesion. In anterior SLAP lesions, the dynamic peel-back sign may be diminished or even absent, because the posterosuperior labral attachment may be secure enough to prevent the labrum from rotating medially over the edge of the glenoid. The primary surgical implication of the peel-back mechanism is that any surgical repair must eliminate the peel-back sign by neutralizing the torsional effect of the biceps twist. This can most effectively be done by a FIG. 3. Single suture anchor placed at the posterior root of the biceps anchor to neutralize peel-back stresses. (Note: All arthroscopic photos are of a right shoulder with the patient s head toward the top of the photo). suture anchor placed into the glenoid bone at the supraglenoid tubercle, under the root of the biceps, with a simple translabral suture tied as a loop just posterior to the root of the biceps (Fig. 3). This fixation configuration will always eliminate the peel-back sign. In contrast, translabral tacks provide, at least visually, less effective resistance to peel-back than suture anchors. From a mechanical standpoint, this arthroscopic observation makes sense. The most effective way to resist an applied torque (e.g., the torsional force that creates the peel-back phenomenon) is by means of an opposing torque applied at the periphery of the torsionally loaded element (in this case the superior labrum) (11 13). With a suture anchor, the circumferential suture loop around the labrum develops tensile forces in response to the applied peel-back torque, providing an effective peripherally placed opposing torque. A translabral tack, on the other hand, has a single point of contact acting at the periphery of the labrum and has to resist the applied torque by means of flexural bending loads on the shaft of the tack, a much less mechanically effective and less predictable means of resisting torque. The literature on SLAP lesion repair documents a higher success rate with the use of suture anchors than with translabral tacks. Specifically, Morgan et al. (9) achieved a 97% success rate (99 of 102) compared with success rates ranging from 71% to 88% with absorbable tacks (11 18). The higher success rates of suture anchors over absorbable tacks is not surprising to us, in view of the more favorable mechanical characteristics of the suture anchors in resisting the pathologic forces. Therefore, for overhead athletes, we prefer suture anchor fixation with one loop placed just posterior to the root of the biceps and additional anchors as needed for the larger lesions. The Pathologic Cascade Everyone who treats throwers should know that a large percentage of them, even asymptomatic ones, have a 76 Techniques in Shoulder and Elbow Surgery

4 Dead Arm Syndrome tight posteroinferior capsule (1). We believe that this is the primary pathologic entity that is responsible for torsional SLAP lesions and the dead arm. To understand the pathologic cascade from tight posteroinferior capsule to disabling torsional SLAP lesion, one must think of the anatomy in dynamic terms, visualizing the stresses that might occur not with the arm at the side but with the arm in abduction and external rotation, the cocked position of the throwing shoulder. With the arm in this position, the posteroinferior capsule, which is the posterior portion of the inferior glenohumeral ligament hammock, will have rotated beneath the humeral head, where it acts as a tight band that tends to push the humeral head in a posterosuperior direction. This repetitive superiorly directed shear force can damage the labral attachments over time. The shear force on the labrum is at its maximum at exactly the point in the pitching cycle (late cocking) where the peel-back forces are maximized, just as the athlete begins to rapidly accelerate the arm. This application of maximum forces at the point of greatest vulnerability is a prescription for disaster in the thrower with a tight posteroinferior capsule. FIG. 4. Circle concept of pseudolaxity, due to the SLAP lesion disruptingthe continuity of the periarticular labral fibers. Instability versus Pseudolaxity Previous investigators have considered subtle anterior instability with anterior capsular stretching to be the primary problem in the dysfunctional throwing shoulder (4,5,7). However, the results of open capsulolabral repair have been less than spectacular, with only 50% of throwers returning to their preinjury level of function. We agree that on cursory arthroscopic review many of these shoulders appear to have some degree of instability, as evidenced by a positive drive-through sign in which the surgeon can easily drive his scope through the shoulder from superior to inferior, between the glenoid and humeral head, with very little resistance. However, if one simply repairs a posterosuperior torsional SLAP lesion, the drive-through sign will almost always be eliminated. This phenomenon indicates that the drive-through sign in the face of a SLAP lesion is actually an indicator of pseudolaxity due to the SLAP lesion rather than true instability. The concept of pseudolaxity is consistent with the circle concept of the periarticular labral fibers acting as a unit (Fig. 4), so that the disruption of the fibers in one part of the labrum may manifest itself as apparent laxity on the opposite side of the glenoid (9). Pagnani et al. (10) have reported in a cadaver model that a complete lesion of the superior portion of the labrum that destabilized the insertion of the biceps resulted in significant increases in anteroposterior and superiorinferior glenohumeral translation. Repairing these posterosuperior labral lesions results in restoration of the circle and elimination of the anteroinferior pseudolaxity. Warren had originally proposed a circle concept as a mechanism for capsular and labral dysfunction in instability, and this concept was presented in reports with his associates (19,20). Our philosophic approach to the question of laxity in the thrower is to be guided by the drivethrough sign. If repair of the SLAP lesion eliminates the drive-through sign, then we do nothing further at the time of surgery. If the drive-through sign persists after SLAP repair, we consider adjunctive capsular suture plication or thermal capsulorrhaphy. However, in the overwhelming majority of patients, SLAP repair alone eliminates the drive-through sign. Bankart lesions rarely occur in conjunction with the dead arm. We have observed Bankart lesions infrequently and then only in longstanding, chronically sore throwing shoulders that suddenly break down. Internal Impingement: Is It Normal or Pathologic? Walch described an intra-articular impingement of the greater tuberosity and rotator cuff against the posterosuperior glenoid with the arm in abduction-external rotation; this became known as internal impingement (8). Internal impingement was noted by Dr. Walch to occur in all shoulders when they were placed in combined abduction and external rotation, and it was not considered pathologic. Dr. Christopher Jobe described this same type of internal impingement in throwing athletes, but he sug- Volume 2, Issue 2 77

5 S. S. Burkhart and P. M. Parten gested that it was a cause of rotator cuff injury. He suggested that internal impingement was pathologic in overhead athletes, and he coined the term posterosuperior glenohumeral impingement (7). We agree with Dr. Walch s opinion that internal impingement occurs normally in all shoulders. If it were pathologic in the throwing athlete, one would expect all throwers to develop shoulder dysfunction, but that is not the case. We noted a 31% incidence of rotator cuff tears in our report on repair of 102 SLAP lesions (9). Most of the cuff tears were partial-thickness articular surface tears, and they were lesion-location specific as they related to the SLAP lesions. That is, the cuff tears that we observed with posterior torsional SLAP lesions were located posteriorly in the rotator crescent, whereas those associated with anterior torsional SLAP lesions were located in the anterior portion of the rotator crescent. We do not think these tears resulted from internal impingement, which would require a mechanism of direct injury to the cuff from contact with the posterosuperior glenoid. Instead, we think that SLAP lesions cause a superior instability with selective tensile failure of cuff fibers that are repetitively overtensioned by superior subluxation of the humeral head. FIG. 5. Angled arthroscopic probe used to test the stability of the biceps/superior labral attachment to the glenoid via the anterior cannula. INDICATIONS AND CONTRAINDICATIONS In our opinion, definitive diagnosis of a SLAP lesion can only be made arthroscopically. Therefore, the indication for SLAP repair is the discovery of a SLAP lesion at diagnostic arthroscopic surgery. The indication for the diagnostic arthroscopy is another matter. SLAP lesions may be incidentally found when arthroscopy is being done for instability, rotator cuff tear, or other categories of shoulder dysfunction. When they are found, they should be repaired. In non-athletes, one might consider fixation by means of a biodegradable tack. However, in athletes, particularly overhead athletes, we strongly believe that a suture anchor technique is the only way to effectively neutralize the peel-back forces that must be resisted by the fixation device. As for contraindications to SLAP repair, we do not think that there are any. Although an asymptomatic SLAP lesion in a relatively inactive individual would not need to be repaired, such a lesion could not be unequivocally diagnosed without an arthroscopy. However, an arthroscopy would not be done in the absence of symptoms. We believe that all SLAP lesions that are seen arthroscopically in symptomatic shoulders with appropriate findings on physical examination should be repaired. PREOPERATIVE PLANNING The senior author has previously reported his results of treatment of type II SLAP lesions, which were classified as anterior, posterior, or combined anteroposterior le- FIG. 6. Angled arthroscopic probe used to assess the displacement of anterior medial angle of the biceps root. A. Stable biceps root with nondisplaceable vertex of biceps/labral angle. B. Unstable biceps root with displaceable vertex. 78 Techniques in Shoulder and Elbow Surgery

6 Dead Arm Syndrome FIG. 7. A and B. The standard anterosuperior portal used to access the superior glenoid for suture anchor placement, suture passing, and knot tying. The portal is located off the anterolateral tip of the acromion, which allows access to the superior glenoid at a 45 angle to the glenoid articular surface. sions according to the portion of the superior glenoid over which they were located (Fig. 1) (9). In general, the Speed and O Brien tests were useful in predicting anterior type II SLAP lesions, and the Jobe relocation test was useful in predicting posterior type II SLAP lesions, as detailed in the senior author s previous reports (1,9). Our routine radiographic series for all shoulder patients includes anteroposterior views in internal and external rotation, axillary view, outlet view, and 30 caudal tilt view. We routinely obtain a magnetic resonance imaging scan on every patient that we are considering for surgery. It has been reported that noncontrast magnetic resonance imaging can accurately diagnose superior labral lesions (21), but that has not been our experience. We have recently begun to obtain contrast magnetic resonance imaging scans, but false-negative studies have continued to be a problem. Although magnetic resonance imaging frequently does not demonstrate the SLAP lesion, it may show other associated lesions (e.g., Bankart lesion, rotator cuff tear, spinoglenoid ganglion cyst). TECHNIQUE Although biodegradable tacks can be used for SLAP repair, we do not use them in the overhead athlete because we do not think that they adequately neutralize the peelback forces. We prefer suture anchors with simple translabral loop sutures. The most critical element to resisting peel-back forces is to position the suture loop just posterior to the root of the biceps, with the loop attached to a suture anchor placed beneath the root of the biceps (Fig. 3). In the past, we have primarily used a screw-in metallic anchor (FASTak, Arthrex, Naples, FL), but we have recently been using a screw-in biodegradable PLA (poly-lactic acid) anchor (Bio-FASTak, Arthrex). We perform SLAP repairs arthroscopically in the lateral decubitus position. Balanced suspension of 5 to 10 pounds is used, with the arm in 30 to 45 of abduction and 20 of forward flexion, using the Star Sleeve Traction system (Arthrex). General anesthesia is administered in each case. A warming blanket is used to prevent hypothermia. An arthroscopic pump maintains the intra-articular pressure at 60 mm Hg. A posterior viewing portal and an anterior working portal are established. As a part of the diagnostic arthroscopy, we use an angled arthroscopic probe to test the stability of the biceps/superior labrum attachments to the glenoid (Fig. 5). We also test whether the biceps root is easily displaceable with a probe (Fig. 6). We test for the drive- FIG. 8. The bone bed is prepared beneath the superior labrum via the anterior cannula usinga motorized shaver (A) to debride the soft tissues from the superior glenoid down to a bleeding bone surface (B). Volume 2, Issue 2 79

7 S. S. Burkhart and P. M. Parten through sign by sweeping the arthroscope from superior to inferior, between the glenoid and humeral head, to see if the scope can be easily driven through the joint. Then we take the arm out of traction and observe the superior labrum arthroscopically as an assistant brings the arm to 90 abduction and 90 external rotation. Performing this dynamic peel-back maneuver in a shoulder with a posterior torsional SLAP lesion causes the entire biceps/superior labrum complex to drop medially over the edge of the glenoid, often quite dramatically (Fig. 2). In general, the arthroscopic signs that confirm a pathologic posterior SLAP lesion are 1) positive drive-through sign; 2) positive peel-back sign (Fig. 2); 3) superior sublabral sulcus >5 mm in depth (Fig. 5); and 4) displaceable biceps root (Fig. 6). It is important to note that isolated anterior SLAP lesions generally have a negative peel-back sign, but the other arthroscopic signs are positive. Once the diagnosis is made, we establish an anterosuperior portal. A spinal needle is used to precisely locate this portal so that it provides a 45 angle of approach to the anterosuperior corner of the glenoid for proper placement of the suture anchor (Fig. 7). The anterosuperior cannula is also used for passing suture through the labrum and for tying arthroscopic knots. Through an anterior portal, we use a motorized shaver to prepare the bone bed on the superior glenoid, beneath the detached labrum (Fig. 8). We do not remove FIG. 9. Arthroscopic suture anchor repair. A. 3.5-mm Spear delivery device (Arthrex, Naples, FL) placed through posterolateral portal (Port of Wilmington) to access posterosuperior glenoid. B. Pilot hole for suture anchor produced by 2-mm punch. C and D. Threemillimeter tap placed through delivery device to create threaded channel for suture anchor. E G. Three-millimeter biodegradable suture anchor (Bio- FASTak, Arthrex), placed through delivery device into prethreaded channel, may accommodate one or two sutures per anchor. 80 Techniques in Shoulder and Elbow Surgery

8 Dead Arm Syndrome FIG. 10. The posterolateral (i.e., acromial) portal (Port of Wilmington) used to approach a posteriorly located type II SLAP lesion for anchor placement. A. Location is 1 cm anterior and 1 cm lateral to the posterior acromial angle. B. Intra-articular view of the angle of access to the posterosuperior quadrant of the glenoid, as viewed with the arthroscope positioned from a standard posterior portal. bone but carefully debride soft tissue down to a bleeding base of bone. Next we prepare for anchor insertion. It is important to realize that a biodegradable screw-in anchor requires a pre-tapped hole in the bone. The Spear guide (Arthrex) is inserted along with a pointed trochar punch that is impacted into the bone with a mallet to create a pilot hole (Fig. 9A and B). Then a tap is placed through the Spear guide to create a helical channel for the screw threads (Fig. 9C and D). Then the Bio-FASTak is inserted up to the laser mark on the inserter, and the inserter is removed (Fig. 9E and F). The eyelet of the Bio-FASTak accommodates one or two No. 2 Ethibond sutures (Fig. 9G). For lesions that extend posteriorly to overlie the posterosuperior quadrant, we place a second anchor through a posterolateral portal (Port of Wilmington) (1,9) (Figs. 10 and 11). The Spear guide is passed through the cuff near the musculotendinous junction of the infraspinatus by this approach. Because the diameter of the Spear guide is only 3.5 mm, we prefer to use it rather than a standard 7-mm arthroscopy cannula in this position to minimize damage to the rotator cuff due to portal placement. Through the posterolateral portal, the only instrument that is placed is the 3.5-mm Spear guide, which is the insertion guide for the FASTak suture anchor. This posterolateral portal is used only for anchor placement. Su- FIG. 11. Relative location of posterolateral portal (Port of Wilmington) access to posterosuperior quadrant of glenoid and anterosuperior portal access to the anterosuperior glenoid. Volume 2, Issue 2 81

9 S. S. Burkhart and P. M. Parten FIG. 12. A single limb of the suture is passed through the labrum with a 45 suture passer (BirdBeak, Arthrex, Naples, FL) through the anterosuperior cannula. The BirdBeak suture passer penetrates the labrum from superior to inferior (A) and grasps the suture from the anchor beneath the labrum (B). The BirdBeak is then withdrawn to pull the suture out through the anterosuperior cannula. ture passage and knot tying are accomplished through the anterosuperior portal. The steps for creating the pretapped hole and inserting the anchor are the same as for the more anteriorly placed anchor. Suture passage through the labrum is the next step (Figs ). We use BirdBeak suture passers (Arthrex) for this step. The 45 BirdBeak is ideal for passing the posterior suture and the 22 BirdBeak is best for the anterior suture. The BirdBeak passer penetrates the labrum from superior to inferior, grasps the suture, and is then withdrawn to pull the suture out the anterosuperior cannula (Fig. 12). Finally we tie the knots. The sutures create simple loops around the labrum that must be very tight to neutralize the peel-back forces (Fig. 13). We prefer to tie stacked reversing half-hitches with a double-diameter knot pusher (Surgeon s Sixth Finger, Arthrex). After the repair, we test the peel-back and drivethrough tests to be sure that they are negative, indicating that the pathology has been corrected. If the drivethrough test were to remain positive, one might consider adjunctive measures for capsular tightening, either by suture plication or electrothermal application. COMPLICATIONS We have seen two loose anchors that had been placed for SLAP repair but were probably never seated in bone. The surgeon must be certain to visualize the anchor going into bone. We have had one patient who developed significant postoperative stiffness that required arthroscopic release. Noncompliance with his early rehabilitation program may have played a role in his stiffness. When the senior author first began using this technique for SLAP repairs, he did not allow external rotation beyond 0 for 3 weeks to avoid peel-back stresses on the repair. With this regimen, return of full motion was sometimes prolonged. Therefore, for the past 2 years we have started passive external rotation immediately, with a goal of obtaining at least 45 of external rotation by 3 weeks after surgery. Arthroscopically, the repairs have appeared secure as the arm was taken through this arc of motion, so we are quite comfortable now that this exer- FIG. 13. A and B. Secure arthroscopic knots are tied usingarthroscopic double diameter knot pusher (Surgeon s Sixth Finger, Arthrex, Naples, FL). 82 Techniques in Shoulder and Elbow Surgery

10 Dead Arm Syndrome FIG. 14. BirdBeak suture passer inserted through the anterosuperior portal with the jaws closed, penetratingthe labrum from superior to inferior. The suture anchor has been previously placed through the anterosuperior portal and free suture ends have been transferred out the anterior cannula. cise does not jeopardize the repair. Since starting early passive external rotation, prolonged stiffness has not been an issue. FIG. 16. BirdBeak suture passer jaws closed to capture suture beneath labrum. POSTOPERATIVE MANAGEMENT We place the operated arm at the side in a sling with a small pillow. All procedures are performed on an outpatient basis, and the patients leave the surgery center with their slings approximately hours after surgery. Passive external rotation is begun immediately. Elbow flexion and extension are allowed right away. The sling is discontinued after 3 weeks. From week 3 to week 6, progressive passive motion as tolerated is observed in all planes. From week 6 to week 16, stretching and flexibility exercises are continued. Passive posteroinferior capsular stretching is begun, as is external rotation in abduction. Strengthening exercises for the rotator cuff, scapular stabilizers, deltoid, and biceps are initiated. At 4 months, athletes begin an interval throwing program on a level surface. They continue a stretching and strengthening program, with particular emphasis on posteroinferior capsular stretching. At 6 months, pitchers begin throwing from the mound. At 7 months, pitchers are allowed full velocity throwing from the mound. They continue posteroinferior capsular stretching indefinitely. One must remember that a tight posteroinferior capsule probably initiates the pathologic cascade to a torsional SLAP lesion, and that recurrence of the tightness can be expected to place the repair at risk in a throwing athlete. FIG. 15. BirdBeak suture passer jaws opened to grasp single limb of suture from anchor beneath labrum. FIG. 17. BirdBeak suture passer is withdrawn from the cannula. Volume 2, Issue 2 83

11 S. S. Burkhart and P. M. Parten FIG. 18. Arthroscopic knots have been tied through the anterosuperior cannula RESULTS We have reported on 102 type 2 SLAP lesions (53 in throwers) without associated anterior instability that underwent arthroscopic repair of the SLAP lesions alone (9). In the group of 53 throwers, all returned to throwing and 87% returned to their preinjury level of throwing. Of the 53 throwers, 44 were baseball pitchers, of which 84% returned to their preinjury performance level or better. The remaining nine pitchers who did not reach their preinjury level of performance had associated undersurface rotator cuff tears. These results in throwers with the dead arm syndrome are far superior to those reported for open capsulolabral reconstruction and reinforce our opinion that the usual cause of the dead arm is the SLAP lesion (either posterior type 2 or combined anteroposterior type 2) rather than instability, and that SLAP repair alone will return the athlete to his preinjury performance level in a high percentage of cases. REFERENCES 1) Burkhart SS, Morgan CD, Kibler WB. Shoulder injuries in overhead athletes: the dead arm revisited. Clin Sport Med 2000;19: ) Rowe CR, Zarins B. Recurrent transient subluxation of the shoulder. J Bone Joint Surg[Am] 1981;63: ) Andrews JR, Carson W Jr, McLeod W. Glenoid labrum tears related to the long head of the biceps. Am J Sports Med 1985;13: ) Jobe FW, Giangarra CE, Kvitne RS, et al. Anterior capsulolabral reconstruction of the shoulder in athletes in overhead sports. Am J Sports Med 1991;19: ) Jobe FW, Tibone JE, Jobe CM, et al. The shoulder in sports. In: Rockwood CA Jr, Matsen FA III, eds. The shoulder. Philadelphia: WB Saunders, 1990: ) Snyder SJ, Karzel RP, Delpizzo W, et al: SLAP lesions of the shoulder. Arthroscopy 1990;6: ) Jobe CM. Posterior superior glenoid impingement: expanded spectrum. Arthroscopy 1995;11: ) Walch G, Boileau J, Noel E, et al. Impingement of the deep surface of the supraspinatus tendon on the posterior superior glenoid rim: an arthroscopic study. J Shoulder Elbow Surg 1992;1: ) Morgan CD, Burkhart SS, Palmeri M, et al. Type II SLAP lesions: three subtypes and their relationships to superior instability and rotator cuff tears. Arthroscopy 1998;14: ) Burkhart SS, Morgan CD. The peel-back mechanism: its role in producing and extending posterior type II SLAP lesions and its effect on SLAP repair rehabilitation. Arthroscopy 1998;14: ) Resnick R, Halliday D. Physics. part I. New York: John Wiley and Sons, 1965; ) Hibbeler RC. Engineering mechanics. 5th edn. New York: Macmillan, 1989; ) Riley WF, Zachary L. Introduction to mechanics of materials. New York: John Wiley and Sons, 1989; ) Berg EE, Ciullo JV. The SLAP lesion: a cause of failure after distal clavicle resection. Arthroscopy 1997;13: ) Pagnani MJ, Speer KP, Altchek DW, et al. Arthroscopic fixation of superior labral tears using a biodegradable implant: a preliminary report. Arthroscopy 1995;11: ) Segmüller HE, Hayes MG, Saies AD. Arthroscopic repair of glenolabral injuries with an absorbable fixation device. J Shoulder Elbow Surg 1997;6: ) Warner JJP, Kann S, Marks P. Arthroscopic repair of combined Bankart and superior labral detachment anterior and posterior lesions: technique and preliminary results. Arthroscopy 1994;10: ) Samani JE, Marston SB, Buss DD. Arthroscopic stabilization of type II SLAP lesions using an absorbable tack. Arthroscopy 2001;17: ) O Brien SJ, Warren RF. Anterior shoulder instability. Orthop Clin North Am 1987;18: ) Pagnani MJ, Deng XH, Warren RF, et al. Effect of lesions of the superior portion of the glenoid labrum on glenohumeral translation. J Bone Joint Surg [Am] 1995;77: ) Connell DA, Potter HG, Wickiewicz TL, et al. Noncontrast magnetic resonance imaging of superior labral lesions. 102 cases confirmed at arthroscopic surgery. Am J Sports Med 1999;27: Techniques in Shoulder and Elbow Surgery