Abstract
Lesions of the long head of the biceps tendon can often be the source of shoulder pain. Pathology of the biceps includes “superior labrum anterior-to-posterior” (SLAP) tears, subluxation, tenosynovitis, hypertrophy, entrapment, adhesions, partial tearing, and complete tearing. The pathology can be managed by benign neglect, debridement, SLAP repair, tenodesis, or tenotomy. A variety of techniques have been developed to perform SLAP repairs and tenodesis.
Keywords
SLAP, long head, biceps tendon, tenotomy, tenodesis
The long head of the biceps tendon has both intra-articular and extra-articular segments. Biceps lesions can occur at the supraglenoid attachment, intra-articularly (lateral to the supraglenoid attachment), or extra-articularly. Regardless of the specific site of pathology, the long head of the biceps tendon is a common source of pain in the shoulder. Debridement, “superior labrum anterior-to-posterior” (SLAP) repair, biceps tenodesis, or biceps tenotomy are options for the treatment of the following lesions ( ):
- 1.
Superior labrum tears from anterior to posterior
- 2.
Partial biceps tears
- 3.
Biceps instability (subluxation or dislocation)
- 4.
Biceps synovitis (the tendon, sheath, or both)
- 5.
Biceps hypertrophy with entrapment
- 6.
Biceps adhesions
Superior Labrum Anterior-to-Posterior Lesions
SLAP lesions offer an interesting and complex challenge to shoulder surgeons. Patients with such lesions present with a wide spectrum of clinical complaints; the findings on physical examination are variable, the clinical findings are nonspecific, and radiographic diagnosis is imprecise. Even at operation the findings are variable, and the decision whether to repair a SLAP lesion requires a thorough understanding of the patient’s clinical condition and shoulder pathophysiology.
Anatomy
The anterior, inferior, and posterior labra are firmly attached to the glenoid, and separation of any of these areas from the glenoid is pathologic. An exception to this is the normal sublabral hole that exists near the anterior-superior glenoid ( Figs. 5.1 and 5.2 ). The superior labrum, in contrast, has wide variability in terms of its attachment to the glenoid. A normal superior labrum is not always attached, or it may have only a flimsy connection to the glenoid. If the glenoid underlying the superior labrum is covered with smooth cartilage and neither the superior labrum nor the glenoid demonstrates any evidence of trauma, we consider this superior labrum separation to be a normal anatomic variant and not a pathologic lesion ( Figs. 5.3 and 5.4 ). Evidence of trauma includes fraying or tearing of the superior labrum or damage to the glenoid cartilage directly underneath the labrum separation. Superior labrum separation without evidence of trauma does not require repair.
A SLAP lesion is an abnormal separation of the superior labrum from anterior to posterior. The entity was first described by Andrews, but Snyder subsequently documented four variations. In a type 1 lesion, the superior labrum is attached to the glenoid rim, but there is fraying of the leading edge of the labrum. In a type 2 lesion, the superior labrum is detached from the glenoid. A type 3 lesion is similar to type 2, but there is also a bucket-handle tear, whereas a type 4 lesion has a longitudinal split in the biceps tendon ( Figs. 5.5–5.11 ).
Several variations of SLAP lesions have subsequently been noted that are essentially on a continuum, based on the propagation of the tear. Labral tearing can propagate anteriorly, posteriorly, or both. SLAP lesions have been identified in many settings and can often be noted in patients with full-thickness rotator cuff tears and those with glenohumeral instability. A number of publications have addressed this lesion’s frequency and the clinician’s ability to diagnose it. There is quite a bit of variability in the normal insertion of the biceps on the supraglenoid tubercle. There can often be a normal cleft that is mistaken for a pathologic lesion. Because of the variability of the anatomy and the lack of clarity on how symptomatic SLAP tears are, the diagnosis is very inconsistent. Some authors have noted that there is a moderate lack of interobserver agreement and a more than expected lack of intraobserver reliability in assessing SLAP tears arthroscopically. Many magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) reports overestimate SLAP tears, and there was a period of time in the past decade when SLAP tear repair reached an alarmingly high rate, suggesting overdiagnosis of symptomatic lesions. That trend has since changed, but it is still not clear if the diagnosis is made appropriately.
Making the Diagnosis
Patients may present with symptoms of intermittent catching, locking, or simply pain of the shoulder during overhead sports or activities of daily living. The pain is often sharp and localized vaguely as “deep within the shoulder joint.” The classic mechanism of acute injury is either a traction event or a fall on an outstretched arm. The other mechanism is recurrent microtrauma such as occurs with overhead throwing. This occurs because of the “peel back” mechanism and is also classified with internal impingement.
Physical examination findings are variable. There have been a plethora of special physical examination maneuvers that can detect SLAP tears. We commonly rely on the active compression test, also known as the O’Brien test ( Fig. 5.12 ). Other tests include the biceps active tests (I and II), the Kim test, the crank test, the clunk test, Speed’s test, and even the apprehension/relocation test ( Fig. 5.13 ). The issue is that several of these tests can be positive for acromioclavicular joint pathology, more distal biceps pathology, and even rotator cuff pathology. However, none of these tests have been noted to be extremely sensitive and specific. Rather, a combination of them will increase sensitivity and specificity to the point where the diagnosis can reasonably be entertained.
As already mentioned, imaging studies are imperfect. MRI is neither highly sensitive nor specific for SLAP tears, but the addition of contrast helps ( Fig. 5.14 ). Even with this, there are many normal variants that make it difficult to diagnose SLAP tears by imaging.
Management of SLAP Tears
Although history, clinical examination, and imaging are very helpful, management of SLAP tears depends greatly on the clinical scenario and associated lesions. Patients with SLAP lesions may present in the setting of subacromial impingement, partial or complete rotator cuff tearing, or glenohumeral instability. In these cases, the surgeon must determine if the SLAP lesion is important. If it is deemed important, does it need to be addressed? Finally, the surgeon must determine how it should be addressed. This issue may have to be resolved prior to surgery or during surgery.
Nonsurgical Treatment
Prior to surgery, clinical examination findings (besides the special exams to diagnose a SLAP tear) include assessment of motion and contractures. Not uncommonly, a posterior capsular contracture or limitation of internal rotation may contribute to symptoms of a SLAP lesion. The symptoms may resolve over time with an effective posterior capsular stretching program. Additionally, scapular dyskinesis may also result in excessive pressure or impingement on the superior labrum. This can be addressed with a scapular stabilizer strengthening program and muscular re-education, along with anterior capsular and pectoralis minor stretching.
Surgical Treatment
Surgical treatment of SLAP tears varies depending on the several factors we have mentioned. At the time of surgery, the decision on how to manage the tear depends on the type of tear and the associated pathology. Several scenarios can be considered for each type of SLAP tear.
Type 1 Superior Labrum Anterior-to-Posterior Lesion
Most often type 1 SLAP lesions are considered nonpathologic, so they are often not addressed. If there is an obvious rotator cuff tear or other labral pathology that is consistent with presentation, there is no reason to address a likely incidental type 1 SLAP lesion. On the other hand, there is likely little negative impact of performing a minor debridement. We leave it alone in most cases.
There are a couple of scenarios in which this lesion may present an issue. The first is that of a young patient, less than 40 years of age, who has impingement symptoms by history and impingement signs on examination. MRI is normal or equivocal. The patient has failed adequate conservative management and a diagnostic arthroscopy is done. At the time of arthroscopy, if there are no other findings in the glenohumeral joint, the type 1 SLAP can be debrided along with a subsequent subacromial decompression upon entry into the subacromial space. If there are any other intra-articular findings that can explain the pain, the type 1 SLAP can be left alone or addressed with debridement if desired ( Figs. 5.15 and 5.16 ). There would not be any indication to repair a type 1 SLAP tear.
Type 2 Superior Labrum Anterior-to-Posterior Lesions
Type 2 SLAP lesions are the ones that cause the most confusion and angst for the surgeon. These lesions are often found at the time of surgery, particularly in older patients. It is difficult to determine if they are symptomatic; whether to address them or not is truly a matter of the surgeon’s judgment. In younger patients, there are often fewer abnormalities to cloud the issue, but it still may be difficult to determine if the SLAP lesion should be addressed.
A simple scenario is that of a young overhead-throwing athlete with an isolated type 2 SLAP tear in the dominant arm. Those tears are addressed with SLAP repair. Another relatively straightforward scenario is that of an older patient (>40 years) with an isolated type 2 SLAP tear in the nondominant arm. This could be addressed with either a SLAP repair or biceps tenodesis, but we generally gravitate toward a tenodesis. SLAP repairs may tend to result in some level of stiffness in older patients, so we generally try to avoid the issue with a tenodesis. The more difficult scenarios are those involving younger patients with isolated type 2 SLAP tears in the nondominant arm or an older patient with an isolated type 2 SLAP tear in the dominant arm. Either SLAP repair or biceps tenodesis would be appropriate in such cases, but the final decision depends on the patient’s symptoms, goals, personality, and exam. For older patients, we still tend to lean toward a tenodesis ( Figs. 5.17–5.19 ).
A common, difficult scenario in a younger patient arises when the surgeon strongly suspects a SLAP tear on clinical grounds, based on history and exam, but the MRI or MRA is either negative or equivocal. There are no other findings on imaging. However, primary impingement, tendinosis, or microinstability with secondary impingement cannot be ruled out by exam or imaging. At the time of surgery, the type 2 SLAP tear may obviously be traumatic, which would make the decision to address it easier. However, often, it simply appears abnormal, with some fraying of the labral attachment, and it can be lifted off the supraglenoid tubercle, revealing underlying cartilage that is worn or damaged but is not obviously pathologic ( Figs. 5.20–5.23 ). Despite this abnormal appearance, it still may be an anatomic variant with mild chronic injury that is not the cause of the symptoms. In this setting, the surgeon must carefully check for subtle signs of anterior-inferior instability, such as labral fraying, fissures, or minor separations. The surgeon should be aware that the SLAP lesion might be causing or exacerbating subtle anterior-inferior glenohumeral instability and that the “impingement” symptoms are secondary. It is usually impossible to determine whether (1) the SLAP lesion is the result of the altered shoulder biomechanics that accompany chronic impingement, (2) the SLAP lesion involves enough altered shoulder biomechanics to cause impingement, or (3) there is any relationship between the two. It is possible that two separate pathologic processes are involved. The clinical history is the ultimate guide as to how to address the lesion. The surgical options are not to address the lesion at all, implement SLAP repair, or do a biceps tenodesis. If there is concern about microinstability and secondary impingement based on the examination or other findings, a SLAP repair is done. If there is any concern that the patient is more likely to have issues with stiffness postoperatively and instability is not the primary issue, a biceps tenodesis may be done. One concept that helps the surgeon reach a decision is whether he or she believes that a subacromial decompression will help. If that is the case, it means that instability is likely not the major concern and perhaps a tenodesis is a better option. However, in overhead-throwing athletes or patients below the age of 30 years, a SLAP repair is usually the preferred option.
Another common scenario is the type 2 SLAP tear encountered when a known rotator cuff tear is being addressed. With the increasing use of arthroscopy, surgeons now routinely inspect the glenohumeral joint and identify type 2 SLAP lesions almost incidentally. Type 2 SLAP lesions are not seen during open rotator cuff repair, so their incidence has been underreported in publications dealing with open techniques. The issue then becomes whether the type 2 SLAP tear is related to the current presentation and whether it should be addressed surgically. We generally use a few factors to make a decision. First, we do not want to divide the patient’s care into two surgeries, one to address the rotator cuff and another to address the SLAP tear later if it is left alone and the patient has persistent symptoms. Therefore we tend to be more aggressive about addressing it surgically if the damage is significant. Second, if the lesion appears minor, we will leave it alone. Third, on the basis of our experience and the published literature, we will not, as a rule, address it with SLAP repair, as we feel that there is a risk of moderate stiffness and pain postoperatively. We will more likely do either a biceps tenodesis or a tenotomy. The tenotomy may be done for patients above 70 years of age, those who are obese, or low-demand patients. The reason for the tenotomy is that even a tenodesis may result in some pain anteriorly, as the tendon in older patients is likely to have some more distal pathology that may generate symptoms. Additionally, the reason to address the lesion at all is that the recovery will be incorporated in the recovery for the rotator cuff repair. If a tenodesis is done, the postoperative care is altered only by limiting active elbow flexion for 4 to 6 weeks.
Type 2 SLAP lesions may contribute to glenohumeral instability directly and indirectly. Some studies indicate that the biceps and its intact attachment play a role in glenohumeral stability. Other studies suggest no role in stability. Regardless of the studies, the superior labrum is continuous with the posterior labrum, so whenever a posterior labral repair is done, the superior labrum, if detached, is also addressed. As for anterior instability, if at the time of arthroscopy it is noted that the superior labrum is continuous with the superior and middle glenohumeral ligaments (as it often is), this suggests that it plays a role in anterior shoulder stability, so it is addressed surgically. Therefore, in a young patient who is undergoing an anterior or posterior labral repair for instability, we will generally repair the type 2 SLAP at the same time ( Figs. 5.24–5.27 ). Care must be taken to do only an in situ repair with no increased tension on the proximal biceps, and the anterior superior labral attachment is left alone.
Type 3 Superior Labrum Anterior-to-Posterior Lesions
Unlike type 1 and 2 lesions where the diagnosis is not clear and the decision-making process is complex, type 3 and 4 SLAP lesions do not pose a diagnostic dilemma. This makes addressing them more straightforward. A true type 3 SLAP tear is not detached from the superior glenoid. It generally needs only debridement, regardless of the associated pathology ( Figs. 5.28–5.30 ).
Type 4 Superior Labrum Anterior-to-Posterior Lesions
Type 4 SLAP lesions can be addressed with debridement, biceps tenotomy, or biceps tenodesis. Usually, the bucket-handle component is detached; once it is debrided, there is no true detachment to repair. If there is a residual detachment, repair may result in overtightening, since some of the labral tissue will have been lost. For this reason we generally do not repair a type 4 lesion. This is surgeon preference; others may consider repair ( Figs. 5.31–5.37 ).
Operative Technique ( )
Before undergoing general anesthesia, patients receive an interscalene block to diminish postoperative pain. The patient is placed in the sitting position. Recordings are made of the range of motion for external and internal rotation with the arm in 90 degrees abduction and the range of motion for external rotation with the arm in 0 degrees abduction. The shoulder is examined for anterior, inferior, and posterior translation and the results are recorded. The shoulder is then prepared and draped routinely. The bony outlines of the acromion and coracoid process are palpated and marked with a surgical marking pen ( Fig. 5.38 ).
The shoulder joint is entered with a cannula and blunt trocar through a posterior skin incision placed approximately 1 cm inferior and 1 cm medial to the posterolateral border of the acromion. The arthroscope is inserted into the glenohumeral joint. The glenohumeral joint is then visually examined. Once the interval has been examined, the location of the anterior-inferior portal is identified with a spinal needle, so that the cannula enters the shoulder immediately superior to the subscapularis tendon and 1 cm lateral to the glenoid. An 8-mm cannula is inserted. The glenohumeral joint is then examined again using a probe from the anterior portal to palpate the labrum, capsule, and biceps tendon. The biceps is pulled into the joint to identify any lesions more distally. If other pathology not involving the biceps is identified that is more easily addressed before establishing an anterior superior portal, that pathology is addressed prior to establishing the anterior superior portal. For example, debridement of an undersurface supraspinatus tear may be done more easily through the anterior inferior cannula with the anterior superior cannula not present. If the superior labrum is the only pathology that needs to be addressed, an anterior superior portal is established with an 8-mm cannula. The reason for two 8-mm cannulas is that often curved suture passers will be used and they will not fit in a 5-mm cannula. If an anterior or posterior labral tear needs to be addressed first, a switching stick is placed at the site of the anterior superior portal to allow the camera to be moved to the anterior superior portal. Even if the superior labrum is all that needs to be addressed, once the 8-mm cannula is placed in the anterior superior portal, the camera can be briefly shuttled here, if desired, to view the posterior structures ( Figs. 5.39–5.45 ).
Type 1 Superior Labrum Anterior-to-Posterior Lesions
These are addressed with simple debridement, as mentioned earlier.
Type 2 Superior Labrum Anterior-to-Posterior Lesions
The high anterior superior portal is critical to obtain a proper angle for the bur and drill. The spinal needle is always used to identify both the entry point and the angle for this cannula. The spinal needle should enter the joint very close to where the biceps exits from the glenohumeral joint and should approach the superior glenoid perpendicularly.
Our prior technique was to use suture anchors preloaded with suture. Our current technique is to use knotless suture anchors. The preloaded suture anchor technique was a very good one, but it left sizable knots in the joint that can be a source of irritation and failure ( Figs. 5.46 and 5.47 ). Regardless of the technique used, the main obstacle for SLAP repair is attaining a good angle of approach for anchor placement. This is an issue with loaded suture anchors or knotless anchors, which is why we emphasize placement of the anterosuperior portal in a high anterior position. Other techniques have been published, using trans-rotator cuff portals such as the port of Wilmington and the Neviaser portal. Our preference is to avoid damage to the rotator cuff if at all possible.
