Throwing Shoulder

 

 

 

 

DEFINITION

The repetitive acceleration and deceleration of the arm during the throwing motion places the thrower's shoulder in extreme positions and under significant stresses, which can lead to chronic overuse-type injuries as well as acute injuries to the throwing shoulder.

The overhead athlete develops well-described adaptations in response to the stresses of throwing, including range-of-motion changes (glenohumeral internal rotation deficit [GIRD]), soft tissue changes, and bony adaptations.

Soft tissue adaptations that occur in overhead athletes result from the large rotational and distractive forces the glenohumeral joint experiences during throwing; over time, this leads to anterior capsular laxity

and maladaptive contracture of the posteroinferior glenohumeral joint capsule.6

Posteroinferior capsular contracture alters the biomechanics of the glenohumeral joint during the throwing motion and produces a predictable constellation of injuries in disabled throwers, termed internal impingement, including superior labral and biceps anchor pathology, undersurface partial-thickness rotator cuff tears that can progress to full-thickness rotator cuff tears, and disruption of the anteroinferior

capsule or labrum.2

Symptoms resulting from these injuries can lead to “dead arm syndrome,” where the throwing athlete cannot compete at a premorbid level due to shoulder discomfort with throwing and resultant loss of pitch

velocity and control.5

Muscle strength imbalances and scapular dyskinesia can contribute to the development of shoulder pain in the throwing athlete and should not be ignored as a potential etiology for symptoms.

 

ANATOMY

 

It is important to consider both native shoulder anatomy as well as adaptive bony and soft tissue anatomic changes in the thrower's shoulder.

 

The scapula plays a critical role in energy transfer from the trunk to the humerus. Eighteen muscles attach to the scapula and control its position on the chest wall.

 

 

Changes in scapular position can lead to external impingement due to anterior tilt, internal impingement, decreased rotator cuff strength, and anterior capsular strain. Altered static and dynamic scapular mechanics arise from overuse and weakness of scapular stabilizers and posterior rotator cuff muscles.

 

A pitcher's shoulder experiences forces equal to nearly half their body weight during the late cocking phase and distraction forces of nearly the entire body weight during the deceleration phase. Professional pitchers can generate up to 92 Nm of humeral rotation torque, which is above the torsional failure limit found in cadavers. The scapular stabilizers and posterior rotator cuff muscles contract violently at ball release and protect the glenohumeral joint from the deceleration force of the arm.

 

The relative position of the glenohumeral ligaments changes with different arm positions. As the arm is brought into full abduction and external rotation (late cocking phase), the posterior band of the inferior glenohumeral ligament (PIGHL) complex moves from a posteroinferior position to a position directly inferior (6 o'clock) in

relation to the glenoid.4

 

As many as five anatomic structures are at risk in the pathologic thrower's shoulder: the posterior superior labrum, the rotator cuff tendon (specifically the articular side of the posterior supraspinatus and anterior infraspinatus), the greater tuberosity, the inferior glenohumeral ligament (IGHL) complex, and the posterior superior glenoid.

 

PATHOGENESIS

Internal Impingement

 

Internal impingement of the shoulder is characterized by excessive or repetitive contact of the greater tuberosity of the humeral head with the posterosuperior aspect of the glenoid when the arm is abducted and externally rotated; this leads to impingement of the rotator cuff and labrum.

 

 

Controversy exists regarding whether internal impingement is a normal or pathologic condition; however, it has most often been described as a chronic, pathologic condition that is associated with throwing and other repetitive, overhead athletic activities.

 

The inciting lesion causing disability in throwers is posterior shoulder muscle weakness due to chronic, repetitive loading.

 

Posterior muscle weakness leads to shoulder dysfunction as a result of both scapular dyskinesis (described in the following texts) and posterior capsular (PIGHL) contracture. One of these pathologic entities may

predominate in the disabled thrower, but they are generally intimately related.6

 

PIGHL contracture develops primarily due to failure of the weakened posterior shoulder muscles to counteract the distraction force of the arm after ball release. This exposes the posterior capsule to abnormal stress due to the forward-flexed and adducted position of the arm at follow-through. Fibroblastic thickening and contracture of the PIGHL occurs as a maladaptive response to these substantial stresses.

 

 

PIGHL contracture can be identified clinically as a scapular-stabilized GIRD in the throwing shoulder.4

 

The thickened PIGHL alters the normal biomechanics of the glenohumeral joint, particularly as the arm is brought into abduction and external rotation (late cocking phase). The center of glenohumeral rotation is shifted posterosuperiorly due to the contracted PIGHL occupying a position directly inferior to the humeral

head in this arm position (FIG 1A,B).7

 

 

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FIG 1 • A,B. Depiction of altered glenohumeral biomechanics due to an acquired PIGHL contracture and the resulting posterosuperior shift in the glenohumeral contact point as the arm is brought from neutral (A) to full abduction and external rotation (B) or late cocking phase. In the fully cocked position, the PIGHL occupies a position inferior to the humeral head, which forces the humeral head superiorly and tethers it posteriorly. C,D. Drawings in the axial plane showing relative relaxation of the anterior capsule in the late cocking position as a result of the posterosuperior shift in the glenohumeral contact point in a shoulder with PIGHL contracture. C. In a normal shoulder, the anterior capsule is taut over the cam shape of the humeral head. D. In PIGHL contracture, the humeral head shifts posteriorly, which decreases tension in the anterior capsule, creating relative laxity. C, center of glenoid.

 

 

Alteration of the glenohumeral contact point leads to a predictable pathologic cascade with continued throwing.4

 

Posterosuperior shift allows greater clearance of the tuberosity over the posterosuperior glenoid rim, enabling pathologic hyperexternal rotation of the arm in the late cocking phase, which leads to the following:

 

An abnormal posteriorly directed shear stress and torsion on both the rotator cuff and biceps insertion point of the labrum. The biceps anchor ultimately fails and “peels back” medially along the posterosuperior glenoid neck (superior labral anterior posterior [SLAP] tear). SLAP tears are typically

anterior and posterior or posterior subtypes of type II tears (the “thrower's SLAP”).10

 

Rotator cuff tears occur because of repeated abrasion and torsion of tendon fibers. Torsion failure is most pronounced on the articular side of the tendons, resulting in the partial undersurface tears most commonly seen in throwers, which may progress to full thickness with continued throwing.

 

 

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Posterosuperior shift of the glenohumeral contact point causes relative relaxation and “pseudolaxity” in the anterior capsule (FIG 1C,D). This is termed microinstability or the acquired anterior capsular laxity that allows increased humeral head translation with arm motion. Although some capsular laxity and increased translation represent functional adaptations, beyond a certain threshold, the increased laxity becomes pathologic.

 

With continued hyperexternal rotation, tension may ultimately cause anteroinferior capsular fiber attenuation, leading to tertiary anterior glenohumeral instability. Discrete “Bankart-type” lesions of the labrum can occasionally occur in this group. Anterior instability is a later event in the pathologic cascade,

not the primary lesion as previously described.8

 

Muscle Imbalances

 

Both symptomatic and asymptomatic throwers have been shown to have imbalances in shoulder muscle strength. The throwing athlete requires a balanced ratio of concentric agonist and eccentric antagonist muscle strength for stability and function.

 

In throwers with internal impingement, imbalances in rotator cuff musculature, including relative weakness of the internal rotators, result in abnormal internal/external rotational strength ratios.

 

 

These imbalances alter the anterior/posterior force couples that stabilize the glenohumeral joint and increase compressive forces in the joint.

 

This also decreases the ability of the shoulder to decelerate during the later phases of throwing.

 

Scapular Dyskinesis

 

In scapular dyskinesis, the position of the scapula on the chest wall is altered owing to loss of scapular elevation and retraction control. The scapula drops (infera), moves lateral from the midline (protraction), and abducts from the midline. The inferior scapular angle may also lift off the chest wall and pitch toward the front of the body (antetilt).

 

 

These changes in scapular position lead to external impingement due to anterior tilt, internal impingement, decreased rotator cuff strength, and anterior capsular strain.9

 

Altered scapular position causes abnormal tension on the insertion of scapular stabilizer muscles and over time leads to inflammation and pain.6

 

The abnormally positioned thrower's scapula has been labeled SICK for Scapular malposition, Inferior medial border prominence, Coracoid pain, and dysKinesis of scapular movement by Burkhart.6

NATURAL HISTORY

 

Throwing athletes manifesting clinical findings of posterior muscle weakness and scapular asymmetry, including decreased pitch velocity, heaviness, or fatigue, without signs of labral or rotator cuff pathology may attempt to correct their shoulder dysfunction with a progressive scapular strengthening program and return to normal function through a pitching program when the asymmetry resolves.

 

Throwers who have vague shoulder discomfort and demonstrate an internal rotation deficit (GIRD) are started on focused internal rotation stretches (“sleeper” stretches) to alleviate PIGHL contracture and restore normal glenohumeral biomechanics and range of motion. GIRD reduction to less than 20 degrees removes the athlete from being at risk for shoulder injury and generally allows return to premorbid function.

 

Pain with throwing is indicative of an injury to glenohumeral structures.

 

 

Once actual injury to glenohumeral structures, particularly the labrum, has occurred, mechanical symptoms ensue and the thrower will more frequently not be able to return to prior function without surgical intervention.

 

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Presenting symptoms typically include subjective feelings of heaviness and sluggishness, stiffness, fatigue, and weakness.

 

Objective indications of dysfunction include decreased throwing velocity, lack of movement on pitches, and decreased accuracy and control.

 

Acute injuries do occur in overhead throwing athletes; however, it is much more common for injuries to be secondary to overuse and fatigue.

 

The timing of onset of symptoms, previous and current treatments, and history of previous shoulder injuries should be determined.

 

In addition to standard history questions, the throwing athlete should be asked questions specifically related to their pitching including changes in mechanics, addition of new pitches, increased pitch count, changes in training, and if injury to other areas of the body (ie, hip, core, lumbar spine) has occurred, which could lead to compensatory alterations in throwing mechanics.

 

Physical examination should not just focus on the shoulder or upper extremity but also on the rest of the kinetic chain including the lower extremities and trunk.

 

Pain is most prominent during the late cocking phase of throwing when the peel-back phenomenon of the superior labrum occurs caused by the posterosuperior glenohumeral shift.5

 

Pain is localized to the antero- or posterosuperior shoulder and is described as “deep.”

 

Mechanical symptoms, such as painful popping, clicking, or snapping, may occur after injury to the superior labrum, particularly during late cocking and early acceleration.

 

The surgeon should check for tenderness in the coracoid, the acromioclavicular joint, and the superomedial scapular angle.

 

Both shoulder girdles must be completely exposed or subtle asymmetry will be overlooked.

 

 

Inspection is done with the patient standing in front of fixed vertical and horizontal references (such as window blinds or door frames) so that affected and unaffected shoulders can be compared for scapular height and malposition (FIG 2).

 

Superior and inferior angles as well as the medial scapular border are marked as a visual reference.

Spinous processes are marked for a midline reference.

 

Asymmetry from the unaffected side when in protraction or infera indicates scapular stabilizer muscle weakness.

 

When in abduction or antetilt, increasing magnitude compared to opposite side signifies scapular muscle weakness.

 

Both active range of motion (AROM) and passive range of motion (PROM) should be assessed with special attention paid to glenohumeral and scapulothoracic motion. The patient should be examined in both the standing and supine positions.

 

 

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FIG 2 • Thrower with right scapular dyskinesis. Scapular asymmetry is highlighted by marking the superior and inferior scapular angles as well as the midpoint of the medial border. Affected right side shows scapular infera and protraction compared to the unaffected left side.

 

 

Glenohumeral PROM is assessed for external rotation (ER) and internal rotation (IR) at 90 degrees of abduction and for ER at 45 degrees of abduction in the scapular plane.

 

 

Increased external rotation with the arm at the side with patient supine can be indicative of rotator interval laxity.

 

Increased external rotation in abduction and external rotation reflects anteroinferior capsular laxity or humeral retroversion.

 

A careful assessment for GIRD must be made. The posteroinferior capsule is evaluated by stabilizing the scapula and passively rotating the arm when it is abducted at 90 degrees. Internal rotational deficits of 15 to 20 degrees can be seen in the throwing arm due to both bony and soft tissue adaptations of the throwing shoulder; however, the overall arc of motion should be similar between the throwing (ts) and nonthrowing

shoulders (nts).

 

 

 

ER + IR = total mobility arc (TMA) IRnts − IRts = GIRD

 

TMAts = TMAnts in healthy throwers

 

GIRDts greater than 20 degrees seen in “shoulders at risk” for injury; generally GIRDts loss of TMAts versus TMAnts

 

Muscle strength should be evaluated after range of motion is determined. The rotator cuff musculature, including subscapularis, should be isolated and assessed.

 

Subacromial impingement is assessed using the Hawkins-Kennedy and Neer tests.

 

Several tests are available to examine the labrum of the throwing athlete. The examiner should use the tests they are comfortable using and develop a consistent pattern of examination. The following tests for type II SLAP lesions in throwers are commonly used:10

 

 

 

FIG 3 • A-B Coronal MRI arthrogram study. The vertically oriented high-signal lesion in the substance of the biceps anchor (circle) suggests a SLAP tear. In addition, there is evidence of partial undersurface tearing of the supraspinatus tendon.

 

 

The modified Jobe relocation test is specific for a posterior subtype. In throwers with SLAP tears, their usual pain is reproduced and they will localize to the posterosuperior joint line (“deep”). Pain in the abduction and external rotation (ABER) position is due to an unstable labrum; anterior pressure reduces the labrum and

relieves pain.2

 

The O'Brien active compression test is specific for an anterior subtype. A positive result is defined as pain with resisted forward flexion and pronation; pain is diminished or relieved with supination.

 

The Speed test is specific for an anterior subtype. A positive result is defined as pain with resisted forward flexion.

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Plain radiographs: anteroposterior (AP), scapular lateral (Y), and axillary views to detect bone or joint space abnormalities

 

 

Possible radiographic findings in association with internal impingement include exostosis of the posteroinferior glenoid rim, sclerotic changes of the greater tuberosity, posterior humeral head osteochondral lesions, or rounding of the posterior glenoid rim.

 

Magnetic resonance imaging (MRI): MRI remains the gold standard imaging modality for young patients with shoulder pain, particularly overhead athletes. The decision whether to include intra-articular contrast is widely debated and depends greatly on the preferences of the radiologists reading the studies. We routinely order intra-articular contrast material because it improves the ability to detect labral and capsular abnormalities as well as partial-thickness rotator cuff tears (FIG 3A,B).

 

 

Typical MRI findings of internal impingement include articular-sided partial-thickness rotator cuff tears and posterior or superior labral lesions.

 

Specialized MRI imaging sequences taken with the affected arm positioned in ABER view can be helpful in this patient population to demonstrate subtle superior labral pathology and partial-thickness rotator cuff tears with delamination.

 

DIFFERENTIAL DIAGNOSIS

 

Subacromial bursitis secondary to rotator cuff weakness and dysfunction

 

Various forms of anterior shoulder pain, acromioclavicular joint dysfunction, and posterior periscapular pain secondary to scapular dyskinesis and the SICK scapula syndrome.6

 

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Pain with throwing may occur with rare conditions such as bone tumors, stress fractures, and growth plate abnormalities in adolescent athletes.

 

NONOPERATIVE MANAGEMENT

 

With a few notable exceptions, conservative options should be exhausted in throwing athletes prior to consideration for surgical intervention.

 

Rest, cryotherapy, oral anti-inflammatory medications, and a supervised phased physical therapy program are the cornerstones of nonoperative treatment.

 

Symptomatic athletes are begun on a scapular reconditioning program combined with internal rotation posteroinferior capsular sleeper stretches.

 

Scapular reconditioning focuses on regaining scapular elevation and retraction control; progress is assessed by repeat examination for normalization of scapular symmetry.

 

 

 

Initially, bilateral shoulder shrugs and rolls are combined with retraction “no money” exercises. The patient progresses to closed-chain “table top” movements and wall-washing motions.

 

Finally, prone “Blackburn"-type exercises are instituted.

 

Strengthening of the periscapular musculature and rotator cuff can minimize hyperextension and external rotation of the glenohumeral joint.

 

Sleeper stretches focus on the posteroinferior capsular contracture that initiates the internal derangement in the glenohumeral joint (FIG 4). Response to a course of internal rotation stretching will determine the extent of the PIGHL contracture.

 

 

90% of athletes will decrease their GIRD to an acceptable magnitude with 10 to 14 days of focused stretching (<20 degrees) with near-normalization of TMAts and TMAnts.

 

The remaining 10% have recalcitrant PIGHL contracture and will show little or no decrease in GIRD after a period of stretching; they are termed stretch nonresponders. These are generally veteran athletes with long-standing GIRD and may require posteroinferior capsulotomy to regain internal rotation.

 

SURGICAL MANAGEMENT

 

In general, indications for surgery in overhead athletes are the same as those in the general public, specifically the failure to improve symptomatically or inability to return to competitive play despite completing a thorough rehabilitation protocol.

 

Athletes presenting with pain and mechanical symptoms during throwing as well as findings suggestive of intraarticular pathology on magnetic resonance arthrogram are indicated for arthroscopic evaluation and treatment.

 

Rarely, posteroinferior capsulotomy is indicated in throwers unresponsive to internal rotation stretching to decrease GIRD. This portion of the procedure is almost never necessary in a young thrower, however.

 

Contraindications to the surgical technique in the following texts include those similar to other elective arthroscopic shoulder procedures.

 

Preoperative Planning

 

Surgical treatment of the throwing shoulder may involve repair of the superior labrum as well as associated injuries to the rotator cuff and anterior capsulolabral structures, as well as contracture of the posteroinferior capsule.

 

 

 

FIG 4 • Sleeper stretch of the posteroinferior capsule of the left shoulder. Patient lies on the affected side to stabilize the scapula and isolate stretch to the glenohumeral capsule. Affected shoulder and elbow are flexed 90 degrees. The opposite hand is used to exert a downward force on the affected arm to stretch the shoulder in internal rotation and decrease PIGHL contracture.

 

 

All pathology must be anticipated before beginning the case, and all necessary instruments and materials need to be present on the back table to prevent intraoperative delays.

 

A fluid pump is used during the procedure to distend the joint and limit bleeding to improve visualization. Prolonged procedures increase the risk of having to perform the surgery through distended tissue, which makes instrument manipulation in the joint difficult and can severely compromise the procedure.

 

The following order of possible interventions is recommended to ease visualization and prevent loss of access to various locations in the joint:

 

 

 

Anteroinferior labral repair (if required) Posterior SLAP repair

 

Anterior SLAP repair

 

 

 

Anterior capsular redundancy (if present) Posteroinferior capsulotomy (if required) Rotator cuff tear (if present)

Treatment of Associated Injury

 

We débride partial-thickness rotator cuff tears that represent less than 50% of the diameter and repair those larger than 50% of the diameter as described in Chapter 10.

 

Anteroinferior capsulolabral injury

 

 

Throwers may develop stretching and attenuation of the anteroinferior capsule, separation of the anteroinferior labrum from the glenoid rim, or a combination of the two.

 

We perform anterior capsulorraphy in the following circumstances:

 

 

Evidence of frayed or attenuated anterior capsule with intact anterior labrum

 

A persistent drive-through sign after superior labral repair or more than 120 degrees of external rotation at 90 degrees of abduction noted during the preoperative examination

 

 

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Posterior capsular release is rarely indicated (about 10% of cases).

 

 

Response to internal rotation stretching is assessed preoperatively.

 

Patients displaying little to no response to stretching (unable to attain GIRD less than 20 degrees) are indicated for capsulotomy to allow restoration of full motion and normal glenohumeral biomechanics.

 

Positioning

 

 

A preoperative intrascalene nerve block is recommended to improve pain control postoperatively. Antibiotics for skin flora are administered.

 

The patient can be positioned in the beach chair or lateral decubitus position depending on surgeon preference.

 

 

We usually favor the beach-chair position for these procedures. In this position, the patient's anatomy can be viewed in situ and visualization of the joint space and subacromial bursa is optimized.

 

After prep and drape, the operative arm is placed in an articulated positioner which allows for positioning of the extremity and gentle traction to improve access and visualization for the various procedures performed (FIG 5).

 

Approach

 

The following arthroscopic portals are used to varying extents in the surgical treatment of disabled throwers (FIG 6A,B):

 

 

Posterior: established first; main viewing portal

 

Direct anterior: main working portal; versatile; may be used for diagnostic arthroscopy, débridement of the articular portion of the rotator cuff, and viewing posteriorly

 

Low anterior: placed just above the superior border of the subscapularis tendon; working portal for anchor placement, capsular plication, and knot tying for anterior labral repair or capsulorraphy

 

Anterosuperior: placed high in the rotator interval anterior to the biceps pulley; used for anchor placement for superior labral repair from the 11 o'clock to 1 o'clock position; knot tying for SLAP repair; ideal for visualization of the anterior labrum during repair or for visualization of the posterior labrum and capsule

 

 

 

FIG 5 • Typical beach-chair positioning. The authors usually favor the beach-chair position for these procedures. In this position, the patient's anatomy can be viewed in situ and visualization of the joint space and subacromial bursa is optimized. After prep and drape, the operative arm is placed in an articulated positioner, which allows for positioning of the extremity and gentle traction to improve access and visualization for the various procedures performed.

 

 

 

FIG 6 • A-B. Portal placement. P, posterior: established first; main viewing portal. A, direct anterior: main working portal; versatile; may be used for diagnostic arthroscopy, débridement of the articular portion of the rotator cuff, and viewing posteriorly. LA, low anterior: placed just above the superior border of the subscapularis tendon; working portal for anchor placement, capsular plication, and knot tying for anterior labral repair or capsulorraphy. AS, anterosuperior: placed high in the rotator interval anterior to the biceps pulley; used for anchor placement for superior labral repair from the 11 o'clock to 1 o'clock position; knot tying for SLAP repair; ideal for visualization of the anterior labrum during repair or for visualization of the posterior labrum and capsule. L, lateral: used for access to subacromial space, rotator cuff repair. 7, posterolateral (7 o'clock position): accessory portal added for access to the posterior labrum for anchor placement and repair.

 

 

Portal of Wilmington: anchor placement in the posterosuperior glenoid; passage of sutures through the posterosuperior labrum. No cannulas are used in this percutaneous portal. Only small-diameter anchor insertion devices and suture passers are used to minimize injury to the cuff musculature because this portal traverses the muscular portion of the posterosuperior rotator cuff.

 

Posterolateral (7 o'clock position): accessory portal added for access to the posterior labrum for anchor placement and repair

 

 

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TECHNIQUES

• Establishing Portals

The posterior portal is established by identifying the posterolateral acromial border and making a 5-mm skin incision about 2 cm medial and 2 to 3 cm inferior to the posterior corner of the acromion in the palpated soft spot between the infraspinatus and teres minor portions of the rotator cuff.

 

 

A blunt trocar is directed from this incision anteriorly with gentle pressure to palpate the space between the rounded humeral head laterally and the glenoid rim medially.

 

The coracoid process is palpated with the opposite index finger and is used as a guide to direct the trocar to the correct plane into the glenohumeral joint.

 

The remaining portals are established after arthroscopic examination of the joint using an “outside-in” technique with an 18-gauge spinal needle.

 

The spinal needle creates minimal soft tissue trauma, and multiple passes can be made as needed to determine the proper location of secondary portals to yield unimpeded trajectories to areas of the joint requiring repair (TECH FIG 1).

 

 

 

TECH FIG 1 • 18-gauge spinal needle is used to localize the anterosuperior portal.

 

• Examination Under Anesthesia

   

  The first step in the surgical management of throwing shoulder is an examination of the patient under anesthesia, as an awake exam is challenging to interpret due to apprehension, guarding, and pain.

   

  The examination under anesthesia should be completed prior to draping so that the affected shoulder can be compared to the contralateral shoulder.

   

  Each shoulder should be evaluated for range of motion and stability, documenting any translation or laxity. Discrepancies in external and internal range of motion can be documented accurately as can instability in the anterior, posterior, and inferior directions using a load and shift maneuver.

   

  Grade 1: mild but normal translation

   

   

  Grade 2: translation over the rim of the glenoid, with spontaneous reduction Grade 3: translation that results in a fixed dislocation

• Diagnostic Arthroscopy

   

  The final surgical plan is determined during diagnostic arthroscopy after structural pathology has been directly visualized and confirmed.

   

  The joint is systematically inspected to ensure that all areas are examined and no pathology is overlooked.

   

  This includes complete visualization and probing of the articular cartilage; the articular side of the rotator cuff; superior, anterior, and posterior labrum; joint capsule; subscapularis; intra-articular biceps tendon and pulley; and the rotator interval structures.

   

  Dynamic evaluation of the shoulder should be performed by bringing the arm in external rotation at 90 degrees of shoulder abduction to evaluate any abnormal contact between the posterosuperior rotator cuff and humeral head with the glenoid.

   

  The following provocative tests can also be performed during diagnostic arthroscopy:

   

  Peel-back test: The posterosuperior labrum is assessed dynamically for evidence of instability in the abducted and externally rotated position (late cocking position). The arm is released from traction and is brought into the full cocking position; an unstable labrum will fall off the glenoid rim and shift medially along the glenoid neck (TECH FIG 2A-D).

   

  Drive-through test: Normally, intact capsular and labral restraints appose the humeral head into the glenoid such that easy passage of the arthroscope from posterior to anterior at the midpoint of the glenoid or sweeping of the scope from superior to inferior along the anterior glenoid rim is not possible. When these maneuvers are possible, they are nonspecific evidence of disruption of the labrum or

  capsular ligaments according to the “circle concept” of glenohumeral stability.2,11

   

  After provocative tests, secondary portals are established depending on the pathology requiring repair as outlined earlier.

   

  A probe is introduced to palpate structures and confirm visual findings (TECH FIG 2A,B).

   

   

  Signs of labral injury may be subtle.5 Careful inspection and probing are often required to detect Fraying and disruption of superior labral fibers inserting into the glenoid

   

  Adjacent irritation of the capsule

   

  Disruption of the smooth contour of the articular cartilage at the glenoid rim

   

  Superior labral sulcus more than 5 mm or a biceps root that can be displaced medially along the glenoid neck

   

   

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  TECH FIG 2 • Diagnostic arthroscopy in overhead athlete with shoulder pain. A. In the beach-chair position with the arthroscope in the posterior portal, a probe is introduced through a standard anterior portal and the labrum is examined, demonstrating a type II SLAP tear. B. The intra-articular biceps tendon is examined and found to be intact without synovitis or tearing. C,D. Examination of the rotator cuff demonstrates partial articular-sided tearing.

  Intra-Articular Débridement

   

  A full-radius motorized shaver is used to gently remove frayed or flap-like tissue and loose debris from the joint.

   

  Careful control of suction pressure on the shaver will ensure that only loose tissue is removed and the bulk of the repairable labrum remains.

• Superior Labral Repair

Portal Placement

 

Portal placement is of critical importance in SLAP repair to facilitate anatomic repair while minimizing associated trauma to the surrounding structures.

 

Anterior and posterior portals are created at an appropriate angle to the face of the glenoid to allow for anchor placement.

 

A high and laterally placed anterior portal can be effective to carry out an isolated repair of the superior labrum. This portal is positioned high and lateral in the rotator interval using a spinal needle for localization. Use of a nonrigid cannula can further facilitate anchor placement posterior to the biceps anchor.

 

Accessory portals that can be used in SLAP repair include the portal of Wilmington (1 cm lateral and anterior to the posterolateral corner of the acromion) or a Neviaser portal (1 cm medial to the acromion within the triangle formed by the clavicle, acromion, and spine of the scapula) (TECH FIG 3A).

 

The appropriate location and direction for the accessory portals should first be established with a spinal needle. A small stab wound is then made in the skin, and the drill guide introduced into the joint (TECH FIG 3B).

 

 

 

TECH FIG 3 • A. Approximate location for the skin incision for the “portal of Wilmington.” B. The appropriate location and direction for the accessory portals should first be established with a spinal needle. A small stab wound is then made in the skin and the drill guide introduced into the joint. (continued)

 

 

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TECH FIG 3 • (continued) C. A high-speed shaver on forward or a small motorized burr is used to remove cartilage from the rim and lateral glenoid neck, yielding a punctate-bleeding cortical bone bed to accept the repaired labrum. D. A suture anchor is placed on the glenoid rim immediately posterior the biceps anchor and suture passed around the labrum. E,F. A PDS suture can be advanced through a spinal needle and used to shuttle one limb of the anchor suture from the anterosuperior portal through the labrum and up through the Neviaser portal. This suture is then retrieved through the anterosuperior portal above the biceps tendon using an atraumatic grasper. G,H. For a standard repair, sutures are tied in a simple configuration with the post-limb suture superior to the labrum. I. This patient also had a full-thickness rotator cuff tear, which was repaired using a standard double-row technique.

Site Preparation

 

The goal of SLAP repair is secure fixation of the biceps anchor to the glenoid rim and stabilization of the peel-back phenomenon.

 

An arthroscopic rasp is used to separate any loose attachments of the labrum to the glenoid rim to mobilize the lesion and free it from medialized scar.

 

A rasp is preferred over a sharp elevator, which can skive and injure normal labral tissue.

 

A high-speed shaver on forward or a small motorized burr is used to remove cartilage from the rim and lateral glenoid neck, yielding a punctate-bleeding cortical bone bed to accept the repaired labrum (TECH FIG 3C). This step is crucial to ultimate healing of the repair.

 

Care is taken while preparing the glenoid rim to avoid collateral damage to the labral tissue, biceps insertion, and surrounding synovium.

Posterior Anchor Insertion

 

Evaluation is made for appropriate anchor location. The number and position for anchors in arthroscopic SLAP repair can be variable and should be delineated based on the location and dimensions of the tear. In the majority of SLAP lesions, the tear extends from the biceps anchor posteriorly, requiring one or two anchors placed posterior to the biceps anchor.

 

We prefer bioabsorbable, tap-in anchors for SLAP repair because they are easier to control during insertion than the screw-in type of anchors.

 

The previously established high and lateral anterior portal used for probing is used for anchor insertion in the superior labral region, including anchors placed just posterior to the biceps anchor.

 

For more posterior anchors, an accessory portal is used (typically, the portal of Wilmington, as described earlier.)

 

A 4-mm skin incision is made and a small sharp trocar or straight hemostat is used to pierce the muscular portion of the posterior rotator cuff as it is advanced into the joint.

 

Penetration of the rotator cuff is done under direct arthroscopic visualization to ensure that the guide enters the joint medial to the rotator cable, which marks the intra-articular location of the musculotendinous junction of the rotator cuff. Because of its small diameter and passage in the muscular portion of the cuff, there is minimal iatrogenic injury with this approach.

 

The trocar or hemostat is removed and the anchor guide is brought immediately onto the glenoid rim adjacent to

 

P.48

the previously prepared bone bed and held firmly in the proper orientation as described previously.

 

An assistant passes the power drill into the guide and carefully advances the drill bit to the hilt.

 

Position of the guide is carefully maintained as the drill is removed and the anchor is introduced in the guide and tapped into a fully seated position in the bone.

 

We insert these anchors to the hilt of the handle of the insertion device.

 

Gentle twisting inline with the anchor is often needed to remove it in dense bone.

 

Alternatively, gentle tapping with a mallet inline can be used to remove the inserter.

 

The guide is removed and the anchor fixation is tested with gentle pulling on the sutures (TECH FIG 3D).

Suture Passage

 

Both suture limbs are brought out the anterior cannula using a looped suture retriever (TECH FIG 3E).

 

The medial suture (closest to labrum) is designated for passage through the labrum.

 

A small-diameter suture-passer device with a retrievable wire loop or a spinal needle with a 0 PDS suture is used to shuttle the suture through the labrum (TECH FIG 3F).

 

The suture-passer device is brought into the joint via the anterosuperior portal.

 

It is used to pierce the labrum from superior to inferior at the location of the anchor to achieve an appropriate bite of labral tissue.

 

The wire loop is advanced over the glenoid rim and retrieved through the anterior portal.

 

The previously identified suture is threaded into the loop and the suture-passer device is gently removed from the portal while shuttling the “post-limb” suture through the superior labrum.

 

Suture passage is done slowly and under visualization so that tangles may be identified and corrected from the anterior portal using the suture retriever.

 

Alternatively, a spinal needle can be placed percutaneously through a Nevaiser's portal position entering the joint through the superior capsule. The needle can then be advanced from superior to inferior through the labrum in the position of the anchor. A PDS suture is then advanced through the spinal needle and used to shuttle one limb of the anchor suture from the anterosuperior portal through the labrum and up through the Nevaiser portal. This suture is then retrieved through the anterosuperior portal above the biceps tendon using an atraumatic grasper. (TECH FIG 3E,F).

 

For a standard repair, sutures are tied in a simple configuration with the post-limb suture superior to the labrum (TECH FIG 3G,H). Alternatively, each limb can be passed forming a horizontal mattress and secured superiorly.

 

Some surgeons prefer knotless techniques for labral repair in this region. For a knotless repair, a suture or small “tape” (broad suture) is passed using one of the techniques described earlier. Both limbs are externalized through the anterosuperior portal and loaded into the anchor system. The anchor position is located and a drill hole is created through a guide. The anchor is then placed and the sutures tensioned to secure the labrum position.

 

The cited steps are repeated as needed for additional posterior anchors in the superior labrum. Anterosuperior Repair

 

Anterosuperior anchors are placed through the anterior cannula with the same orientation concerns and technique as described for posterior anchors.

 

Anterior suture limbs are passed and retrieved through the same anchor, which can create tangling of sutures. In addition, given the orientation of passage and retrieval of anterior sutures through the anterior cannula, a “sawing” effect can be created as the suture is drawn through the tissue, which may damage the anterosuperior labrum.

 

It should be noted that anchors anterior to the biceps anchor should be placed judiciously, as there is anatomic variability in this region. In most SLAP lesions, posterior anchors alone are able to stabilize the biceps labral complex and normalize the peel-back phenomenon.

 

When anterior anchors are required, care should be taken to repair the labrum without incorporating the anterior capsule, middle glenohumeral ligament, or rotator interval structures to avoid associated motion loss. Dynamic Assessment of Repair

 

Peel-back test: The peel-back phenomenon should be obliterated and the labrum should remain firmly fixed to the superior glenoid during full cocking of the arm (TECH FIG 3H).

 

Drive-through test: Advancement through the joint at midglenoid should not be possible after SLAP repair; if this test continues to be positive, then additional anteroinferior capsular redundancy is likely (see the following texts).

Partial-Thickness Rotator Cuff Repair

 

In the overhead population, partial-thickness rotator cuff tears are most commonly found posterior to the rotator cable and can have varying degrees of intrasubstance delamination.

 

“Low-grade” tears involve less than 50% of the thickness of the rotator cuff insertion and are ideally addressed with débridement and management of any associated pathology.

 

For partial-thickness articular-sided tears making up greater than 6 mm (or 50%) of the rotator cuff

footprint, consideration should be made for formal repair.

 

The repair technique and construct chosen is determined by tear characteristics such as location, depth, and tissue quality.

 

A PDS suture is placed through the tear so that the tear may be accurately evaluated on the bursal side.

 

Prior to tendon repair, a complete bursectomy and acromioplasty are performed for better visualization. The tissue marked by the PDS suture is evaluated to confirm that the tear is truly partial thickness and does not have substantial bursal-sided involvement.

 

Once the tissue is deemed reasonable for either traditional or transtendinous repair, the arthroscope is reintroduced into the glenohumeral joint.

 

P.49

 

 

 

TECH FIG 4 • Intratendinous repair of a partial articularsided rotator cuff tear. A. The partial-thickness tear is identified and held in placed with two spinal needles placed percutaneously through the tendon. B,C. A PDS suture is placed through each needle and shuttled through an anterior portal. D. Nonabsorbable sutures are then used to replace each of the PDS sutures. E. The nonabsorbable sutures are then retrieved in the subacromial space and tied arthroscopically, creating a mattress configuration that reduces the articular-sided partial defect and closes the intrasubstance delamination.

 

 

In the setting of a high-grade partial articular-sided tear (PASTA), repair is generally carried out by completion of the tear and formal repair of the full-thickness defect.

 

The extent of the tear is visualized intra-articularly and the remaining bursal insertional fibers are sharply detached.

 

The tuberosity is carefully débrided with stimulation of bony bleeding to encourage healing.

 

A single row or transosseous equivalent repair is then carried out with the goal of anatomically reinserting the rotator cuff tissue over the extent of the footprint without overtensioning the involved musculotendinous unit.

 

An alternative option in circumstances where there is a significant intrasubstance delamination injury is intratendinous repair.

 

The first step of this technique is to visualize the tear and confirm that the inner lamina of the tear can be reduced anatomically (TECH FIG 4A).

 

Next, the footprint bone is débrided to stimulate healing in a similar fashion to standard repair.

 

An atraumatic grasper is used to reduce the inner lamina, which is held in place while paired spinal needles or suture shuttle devices are placed percutaneously through the tendon from bursal to articular. Sutures are advanced and brought through the anterior cannula and used to shuttle a mattress suture reducing the tear. Additional mattress sutures are passed based on tear size and configuration (TECH FIG 4B-D).

 

The sutures are then tied arthroscopically in the subacromial space, compressing the delaminated layers of the tendon and restoring the tendon's prior structure (TECH FIG 4E).

 

One or more suture anchors can be added to this construct to add further stability based on surgeon preference.

 

Full-thickness tears of the rotator cuff in the throwing athlete population are approached much like those in the nonathletic population.

 

It should be noted that this patient population can be poorly tolerant to overtensioning and thus more rigid repair constructs may be less effective. Every effort should be made to repair structural pathology without altering the normal anatomy and architecture of the rotator cuff insertion.

• Mini-Plication of the Anterior Capsule

   

  The extent of capsular plication is subjective. The goal is to reduce the redundant capsule by placing sutures sequentially from inferior to superior to eliminate anterior instability while preventing inadvertent restriction to full external rotation (TECH FIG 5A,B).

   

  A rasp or “whisker” shaver is used to abrade the capsule to aid in healing of the plication (TECH FIG 5C,D).

   

  No. 1 PDS sutures are placed beginning anteroinferiorly with pointed suture advancement instruments of varying curvatures.

   

  A “bite” capsule is taken laterally and advanced and sutured to the anteroinferior labrum, obliterating a redundant anterior recess (TECH FIG 5E,F).

   

  Placement of sequential sutures allows for repeat examination to ensure anterior stability is restored without creating motion restriction (TECH FIG 5G).

   

  Rarely, a discrete anteroinferior labral avulsion from the glenoid is present that is repaired as described elsewhere in the text. This is most easily accomplished before superior labral repair.

   

  An additional anteroinferior portal may be required to achieve an appropriate anchor insertion angle onto the glenoid rim and to ease suture passage and management.

   

  P.50

   

   

   

  TECH FIG 5 • A. Multiple anterior plication sutures are used to obliterate redundant anteroinferior capsular tissue. B. Diagram in axial orientation to the glenoid showing accordion-like plication and shortening of the anterior capsule as it is sutured to the labrum. C. An arthroscopic rasp is used through the anterosuperior portal to abrade the capsular tissue and generate a healing response in the tissue after plication. D. Anterior capsule after abrasion and before suture placement. E. Starting anteroinferiorly, a pointed suture-passing device is used to suture a bite of lateral capsule to the labrum, as shown in F. As the knot is tied, this suture effectively shortens and reduces the anterior capsule. G. Multiple no. 1 PDS anteroinferior capsular plication sutures after tying of the final and most superior plication stitch.

   

   

   

• Posteroinferior Capsulotomy

P.51

 

As stated earlier, a posterior capsulotomy is indicated only in patients unable to attain a GIRD of less than 20 degrees to allow restoration of full motion and normal glenohumeral biomechanics (TECH FIG 6A).

 

Arthroscopic findings in these recalcitrant cases include inferior recess restriction and a thickened PIGHL

(more than 6-mm thick).

 

The procedure is carried out most commonly with the arthroscope positioned in the anterosuperior cannula and instruments placed through the standard posterior portal (TECH FIG 6B).

 

A hooked-tip arthroscopic electrocautery with long shaft is used to create a full-thickness capsulotomy from the 6 o'clock to the 3 or 9 o'clock position in the posteroinferior quadrant.

 

 

 

TECH FIG 6 • A. Location of the posteroinferior quadrant capsulotomy. B. Intraoperative view showing the instrument placement for posteroinferior quadrant capsulotomy. The arthroscope is in the standard posterior viewing portal and the cautery is in the portal of Wilmington. A small-diameter cannula (5.5 mm) may be required for passage of the hook-tipped cautery device through the portal of Wilmington. C. View of the posteroinferior capsule showing thickening and restriction of the inferior recess. D. The hook-tipped cautery is used to successively divide the capsule about 3 to 5 mm from the labrum under direct visualization. E. Completed capsulotomy. Muscle fibers just posterior to the capsule are visible between the divided edges of the capsule.

 

 

The capsulotomy is made approximately a quarter inch from the labrum.

 

Gentle sweeping motions are used to successively divide tissue under direct visualization (TECH FIG 6C-E).

 

It is critical to perform the procedure without chemical paralysis induced by the anesthesia staff.

 

Muscular twitching will alert the surgeon that the electrocautery is too close to the axillary nerve with the potential for neurologic injury.

 

If this occurs, the capsulotomy should be shifted to a more superior and medial position or abandoned altogether if no safe zone is found.

 

Posteroinferior capsulotomy typically results in a 50- to 60-degree increase in internal rotation

immediately postoperatively.

 

 

 

P.52

 

PEARLS AND PITFALLS

 

Physical examination

• Examiner must stabilize the shoulder girdle with anterior pressure over the glenohumeral joint to negate scapulothoracic motion while performing range-of-motion measurements and determining total mobility arch and glenohumeral internal rotation deficit. Failure to measure isolated glenohumeral motion will yield erroneously high values that are useless in diagnosing the pathology and monitoring treatment.

   

  Positioning ▪ All procedures can be carried out in the beach-chair or lateral decubitus positions.

  The beach-chair position offers circumferential access to the glenohumeral joint and superior visualization in the subacromial space.

   

  Steps to avoid shoulder distention when using a fluid pump

• An efficient surgical plan should be developed before the case; it is modified as needed after diagnostic arthroscopy. The surgeon should work expeditiously; sufficient arthroscopic skills, including suture passage and knot tying, are required.

• All anticipated instruments should be open on the back table at the start of the procedure.

• The pump should be turned off if a pause in the procedure is needed.

• An assistant should hold cannulas in the joint once they are passed through the capsule, particularly during suture passage and knot tying, or the cannulas will back out and allow distention of superficial tissues.

   

  Suture anchors

  • Small absorbable anchors are recommended for labral procedures. Knots should be secured on the periphery of the joint to avoid irritation of the surrounding soft tissues or chondral wear during subsequent joint motion or athletics. Alternatively, knotless labral fixation can be used.

     

    Suture passage

  • Tangling of sutures during suture passage can easily occur. It is also easily corrected when there is slack in the sutures. Suture limbs should be passed slowly and under visualization to allow for corrections.

     

    Knot tying ▪ The surgeon should not attempt to tie knots percutaneously because tissue will interfere with sliding and tightening of the knot. Suture limbs should be transferred to a cannula for knot tying.

    • An assistant should point and stabilize the cannula at the anchor to simplify tying.

    • The surgeon should learn and become proficient with one sliding and one nonsliding knot.

 

POSTOPERATIVE CARE

 

 

Follow-up

 

Procedures are performed on an outpatient basis.

 

 

Ice or cooling pad is encouraged for first 72 hours postoperatively. Sutures are removed at ˜ 10 days postoperatively.

 

Starting at 1 week, self-directed range-of-motion exercises are begun under specific guidelines (see following texts). Patients are seen regularly to assess progress and modify rehabilitation as needed.

 

REHABILITATION TIME TABLE

 

Immediate

 

 

 

Passive external rotation with arm at side (not abduction) within specific parameters Elbow flexion and extension

 

Capsulotomy patients are started on sleeper stretches on postoperative day 1.

 

Weeks 1 to 3

 

 

Pendulum exercises

 

 

PROM using pulley device in forward flexion and abduction to 90 degrees only Start shoulder shrugs and scapular retraction exercises in sling.

 

 

Sling should be worn when not out for exercises. Weeks 3 to 6

 

Sling is discontinued between 4 and 6 weeks.

 

 

PROM is advanced to full motion in forward flexion and abduction. Sleeper stretches are started in patients not having capsulotomy.

 

Weeks 6 to 16

 

 

Stretching and flexibility exercises are continued.

 

 

 

Passive external rotation stretching in 90 degrees of abduction is begun. Strengthening for rotator cuff, scapular stabilizers, and deltoid is started at 6 weeks. Biceps strengthening is delayed until 8 weeks.

 

Daily sleeper stretches are continued.

 

4 months

 

 

Interval throwing program on level surface

 

Stretching and strengthening is continued (internal rotation stretches are emphasized).

 

6 months

 

 

 

Pitchers begin throwing full speed depending on pain-free progression through interval throwing program. Continue daily internal rotation stretches.

 

7 months

 

Full-velocity throwing from mound

 

Sleeper stretches and scapular conditioning are performed daily indefinitely while the patient continues throwing competitively.

 

OUTCOMES

 

Burkhart et al3: SLAP repair in high-level throwers: 182 pitchers treated over 8 years (one-third professional, onethird college, one-third high school)

 

Ninety-two percent returned to premorbid performance or better.

 

 

Average UCLA score was 92% excellent at 1 year and 87% excellent at 3 years. The 164 pitchers undergoing SLAP repair and posteroinferior capsular stretching

 

Average GIRD = 46 degrees preoperatively, 15 degrees at 2 years

 

 

Eight pitchers undergoing SLAP repair and posteroinferior quadrant capsulotomy Average GIRD = 42 degrees preoperatively, 12 degrees at 2 years

 

Average fastball velocity = 11-mph increase at 1 year

 

 

P.53

 

Brockmeier et al1: prospective outcomes after arthroscopic repair of type II SLAP lesions in 47 patients, 34 of which were athletes

 

Eighty-seven percent rated the outcome as good or excellent.

 

Median American Shoulder and Elbow Surgeons (ASES) and L'Insalata scores were 97 and 93, respectively.

 

Twenty-five out of 34 (74%) of athletes were able to return to their preinjury level of competition.

 

 

Van Kleunen et al12: Retrospective study of 17 high-level baseball players with GIRD and both a SLAP tear and more than 50% infraspinatus tear who underwent surgical repair of both injuries.

 

 

Only 6 patients were able to return to the same or superior level of performance. Five patients returned to play at a lower level or switched positions.

 

Six patients were unable to return to play.

 

More than 50% tear of the infraspinatus in combination with SLAP tear and GIRD results in guarded prognosis in return to play at the same level.

 

COMPLICATIONS

Similar to other arthroscopic shoulder reconstructions: rare incidence of infection, failed repair, painful adhesion formation, subacromial irritation; stiffness

Physicians and therapists must be vigilant about development of postoperative stiffness in overhead athletes. Stiffness can be addressed effectively with modification of the rehabilitation program if it is identified early with regular follow-up and directed therapy.

 

REFERENCES

1. Brockmeier SF, Voos JE, Williams RJ III, et al. Outcomes after arthroscopic repair of type-II SLAP lesions. J Bone Joint Surg Am 2009;91(7):1595-1603.

    

    

2. Burkhart SS. Arthroscopically-observed dynamic pathoanatomy in the Jobe relocation test. Presented at Symposium on SLAP Lesions. 18th Open Meeting of the American Shoulder and Elbow Surgeons, Dallas, TX, Feb. 16, 2002.

    

    

3. Burkhart SS, Morgan CD. SLAP lesions in the overhead athlete. Orthop Clin North Am 2001;32:431-441.

    

    

4. Burkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology, part I: pathoanatomy and biomechanics. Arthroscopy 2003;19:404-420.

    

    

5. Burkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology, part II: evaluation and treatment of SLAP lesions in throwers. Arthroscopy 2003;19:531-539.

    

    

6. Burkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology, part III: the SICK scapula, scapular dyskinesis, the kinetic chain, and rehabilitation. Arthroscopy 2003;19:641-661.

    

    

7. Grossman MG, Tibone JE, McGarry MH, et al. A cadaveric model of the throwing shoulder: a possible etiology of superior labrum anterior-to-posterior lesions. J Bone Joint Surg Am 2005;87A:824-831.

    

    

8. Jobe CM. Posterior superior glenoid impingement: expanded spectrum. Arthroscopy 1995;11:530-537.

    

    

9. Kibler WB, Kuhn JE, Wilk K, et al. The disabled throwing shoulder: spectrum of pathology-10-year update. Arthroscopy 2013;29(1):141-161.

    

    

10. Morgan CD, Burkhart SS, Palmeri M, et al. Type II SLAP lesions: three subtypes and their relationship to superior instability and rotator cuff tears. Arthroscopy 1998;14:553-565.

     

     

11. Panossian VR, Mihata T, Tibone JE, et al. Biomechanical analysis of isolated type II SLAP lesions and repair. J Shoulder Elbow Surg 2005;14:529-534.

     

     

12. Van Kleunen JP, Tucker SA, Field LD, et al. Return to high-level throwing after combination infraspinatus repair, SLAP repair, and release of glenohumeral internal rotation deficit. Am J Sports Med 2012;40(11):2536-2541.