In our population of professional overhead throwers, complaints of shoulder pain are investigated with a thorough history and physical exam. As we expect an MRI to demonstrate labral changes regardless of the cause of the player’s pain, MRIs are reserved for recalcitrant cases. Key aspects of the patient’s history are the locations of pain and the provocative phase or phases of pitching. Appreciating the stress on anatomic structures during the phases of pitching facilitates the diagnosis. In our experience, posterior pain with late cocking usually indicates a posterior superior labral tear or hypertrophy with or without undersurface tearing of the infraspinatus-supraspinatus junction. This is commonly referred to as “internal impingement” and is often caused by a flap of tissue (either labral or cuff) being trapped in the cocked position. Posterior pain during release or follow through is most commonly indicative of an eccentric failure of the posterior rotator cuff. Anterior pain during cocking is typically associated with some degree of dynamic anterior instability which can be multifactorial (cuff weakness, scapular dyskinesia, capsular laxity, labral pathology, etc.). Anterior pain with “finishing” the throw or terminal stage of follow-through can indicate mechanical impingement of the bicep or lesser tuberosity on the coracoid. These must all be questioned during the history, correlated with a provocative physical exam and critically evaluated with imaging, especially the MRI.

On physical exam, special attention to labral signs is helpful, with the O’Brien sign and Jobe Relocation test. Less commonly performed tests can be helpful in the throwing population such as the “Internal Impingement Sign” which is positive when posterior pain is reproduced by exaggerating the cocked position, especially with horizontal extension in the 90 degrees abducted position. Reproducing the patient’s localized pain in the posterior joint line during this maneuver indicates mechanical entrapment of posterosuperior labrum, rotator cuff tissue or both. This maneuver is similar to performing apprehension testing in the standing position but with increased horizontal extension. The patient must not only identify if this position is painful or uncomfortable, but specifically where the discomfort is located as well as the character of the pain (pinching/catching versus pain or apprehension) (Fig. 1). The deceleration sign is positive when the eccentric contraction of the humeral decelerators is painful in the follow through position. This is tested by placing the patient in the follow through position of throwing and applying downward pressure to the wrist while the patient resists the applied force. Posterior pain is suggestive of inflammation and eccentric failure of the posterior rotator cuff (Fig. 2). Scapula Dyskinesia and scapular posture can be assessed by inspecting scapular kinesis from behind with the patient moving his arm through all planes including internal and external rotation in the 90-degree abduction position. Thorough evaluation of winging, relative protrusion, and fluid movements of glenohumeral motion with relation to scapulothoracic motion. Hitches, sudden jump/catches, or pain should be assessed with shoulder flexion. Tightness of the posterior capsule is assessed with the patient supine and the examiner immobilizing the scapula against the table. The examiner pushes the humerus across the chest while stabilizing the lateral border of the scapula and keeping the forearm in neutral rotation to prevent coupled external rotation. The shoulder will externally rotate as the arm is pushed into adduction as the posterior-inferior capsule comes under tension. This must be resisted by the examiner in order to obtain accurate and reproducible results. A tight capsule will prevent the elbow from passing through the midsagittal plane, while a flexible capsule will allow movement almost to the midline. Reproduction of pain with the supine cross body test is indicative of posterior capsule tightness as the pain generator (Fig. 3).

The evaluation in non-overhead throwing athletes is similar to an overhead thrower, but the positional tests specific to throwing are deferred. The strength of the rotator cuff is evaluated in multiple planes, and signs specific to the long head bicep tendon are prioritized. Reproduction of symptoms with rotator cuff tests, impingement signs, and bicep tests is important. Specifically checking for coracoid impingement in those with anterior pain can be illuminating. The critical assessment of the posterior capsule and potential cuff contracture is imperative especially with the shoulder in 90 degrees of abduction. Comparisons between the symptomatic extremity relative to the asymptomatic side aid in determining the baseline from symptomatic pathology.

Fig. (1). Clinical photograph demonstrating positioning of the Internal Impingement Test. The patient must delineate the location and character of pain (pinching, catching, and instability). Localized pain in the posterior joint line is suggestive of internal impingement.

Fig. (2). Clinical photograph demonstrating position to assess for a Deceleration sign. With the patient in the follow through position of pitching, posterior pain with applied downward pressure of the wrist is suggestive of inflammation potentially due to eccentric failure or excessive strain of the posterior rotator cuff.

Fig. (3). Clinical photograph demonstrating positioning to assess for Posterior Capsule Tightness. The forearm must be kept in neutral rotation to adequately access the posterior inferior capsule. An inability of the elbow to cross the midsagittal plane is suggestive of tight posterior capsule.

Our data has demonstrated that surgical treatment of SLAP lesions in throwers has a significantly lower success rate compared to directed rehabilitation that prioritizes the posterior capsule flexibility and scapula positioning. Up to 85% of patients with isolated SLAP tears treated with non-operative management have done well. While many authors have reported good results with surgical repair [18, 21, 28-30], the criteria used do not accurately reflect on-the-field performance. Rather than, examining traditional subjective outcome measures or physical findings such as range of motion or strength, we studied the actual competitive performance of professional pitchers who had MRI documented SLAP lesions that failed a course of Physical Therapy (PT) and underwent surgical SLAP repair. When true baseball performance metrics were applied to pitchers, for those that underwent surgery, the return to play rate was 48% with a return to prior level of play rate at 7% compared to 40% with a return to play rate and a return to prior level of play at 22% rate for those who participated in physical therapy with a focus on cross body stretch and scapular posture [19]. Since that study was completed, we have noted an even higher success rate with non-operative management. We have found that in our overhead athletes, prognostic indicators of successful non-surgical management are a tight posterior capsule with a stretch that reproduces the pain and scapular dyskinesis with a forward rotated and protracted posture.

The role of posterior capsule and posterior rotator cuff tightness in the painful thrower’s shoulder has been well described [31-33]. This can be evaluated through the assessment of Glenohumeral Internal Rotation Deficit (GIRD) which is measured with the arm in 90 degrees of shoulder abduction and 90 degrees of elbow flexion (90-90 position) with comparisons of each side with internal and external rotation. This assessment provides an easy and reproducible measure of capsular maladaptation in this direction. Whether a portion of the loss of internal rotation is caused by bony retroversion is irrelevant since in practicality the bony component cannot be corrected. Wilk et at showed that within 122 professional baseball players the total arc of motion averaged 193 degrees with 130 degrees of external rotation and 63 degrees of internal rotation [34]. Of the players that demonstrate GIRD, they were twice as likely to get injured in a three-year window [35]. Posterior capsule and rotator cuff tightness is most commonly treated with internal rotation stretching at 90 degrees of shoulder abduction in a sleeper stretch and passive internal rotation stretching at 90 degrees of shoulder abduction. Other adaptations have provided improved results in the correction. McClure et al demonstrated that self-applied seated cross-body stretch with internal rotation and no scapular stabilization provided greater internal rotation [36]. Muscle energy techniques have also demonstrated greater immediate effects especially in cross body and internal rotation. Moore et al demonstrated in division 1 college pitchers that resisted contractions and relaxation of three reps in crossbody with internal rotation is more effective than similar techniques applied in internal rotation [37]. The stretching protocol can be a long arduous process, as pitchers involved with these stretches for a prolong period of time of three or more years have shown a greater total arc of the dominant side compared to their non-dominant side. For pitchers that have participated in these stretches for less than three years, the total arc of motion was almost equivocal [38]. Despite these common stretches, the mid-posterior capsule can remain tight even in those who enrolled in a stretching program and demonstrate improved internal rotation at 90 degrees. While certainly a step in the right direction, we have found the sleeper stretch and the self-administered cross-body stretch to be insufficient in the overhead athlete population. There is a subset of patients whose posterior capsule remains tight in cross-body adduction despite improvement in sleeper stretch internal rotation. If not specifically inspected, this is easily overlooked. These patients will note that this specific stretch of the posterior capsule is painful and, most importantly, reproduces their symptoms.

Patients participating in an internal rotation stretching program have found stretching with their hand behind the back similar to the “Towel Stretch” commonly performed during post-surgical rehabilitation. We do not recommend this stretch or motion for throwers as it promotes a forward rotated and protracted scapular position which increases stress of the anterior-superior capsule.

Scapular malposition of anterior tilt, protraction and upward rotation is commonly seen in overhead athletes [39]. Scapular malposition at rest has also been demonstrated to result in glenoid anterior tilting creating an increased contact in the posterior shoulder due to the increased hyperangulation [40]. Closed chain exercises have been proven to correct scapular malposition in protraction, retraction, elevation and depression [41]. In addition to correct scapular posture, focus on strength and conditioning of periscapular muscles are essential to the stamina and proper mechanics of pitching. In professional baseball pitchers, it has been shown that as scapular musculature fatigues, scapular position increases with anterior tilt and protraction resulting in decreased internal rotation [42, 43].

In throwers with scapular dyskinesia, a simple in-office demonstration can convince the patient that scapula posture control is important for success with non-operative management. This can be demonstrated by starting the patient in their baseline standing position and bringing the arm into a maximally cocked position while holding the scapula in the protracted posture causing the patient to feel the significant strain on their elbow and shoulder. The patient is then later instructed to “Set” their scapula with retraction which allows them to bring their arm further into a cocked position with ease and a lack of discomfort. With the scapula retracted, the shoulder and elbow experience significantly less strain which is immediately apparent to the patient. This demonstration often fosters greater patient commitment towards non-operative management and deters those who may have been biased toward surgical intervention for their observed MRI findings rather than their actual functional pathology.

Rehabilitation is best performed by a physical therapist or certified athletic trainer well-versed in these concepts and baseball throwing mechanics. Assessment of mechanics by a qualified professional is critical to confirm that the player maintains adequate scapular posture while throwing. Having a throwing lane in the therapy clinic is also helpful for observation and analysis of pitching mechanics.

Although posterior stretching has been demonstrated to be successful in 66.7 to 90% of athletes [13], in the cases of patients that have addressed their mechanics, posterior capsule flexibility, and scapular posture, yet fail to successfully return to competition due to continued symptoms, surgical intervention may be necessary. In cases of internal impingement secondary to a hypertrophic labrum or small partial articular-sided cuff tear, debridement of rotator cuff and/or labral flaps is imperative and may be sufficient alone. During the 2017 AOSSM annual meeting Sugaya et al demonstrated that overhead athletes with stable Type II SLAP lesions and concomitant PASTA lesions did well with debridement of the posterosuperior labrum and PASTA lesion. For overhead athletes with extensive detachment of the anterior and posterior portion of the labrum, the anterior superior labrum was repaired while the posterosuperior labrum was debrided. Meantime and return rate to play were similar between the debridement only group and the repair group [44, 45]. Debridement of the typically bulky posterior labrum minimizes posterior impingement when cocked. When evaluating softball and baseball players, Ciccotti et al demonstrated that 79.5% of their athletes were able to return to their prior level of activity after surgery. Of these players 84% of pitchers and 72% of the position players were able to return to play [17]. For the case of isolated tight posterior capsules, posterior inferior capsular release has shown to be effective in returning 11 of 16 throwers to their pre-injury level of participation. Two of the 16 had a reduction in pain while the other 14 of 16 had an elimination of pain [46]. Yung et al followed 13 overhead athletes with SLAP repairs for 28 months and found that only 4 were able to return to prior levels at 11 months, while 1 never did [47]. In a systematic review which included 506 athletes, 198 overhead athletes, 81 of which were pitchers, 83% of all athletes reported good to excellent satisfaction rates and a return to previous level of play rate at 73%. When looking at only overhead athletes 74% expressed satisfaction of good to excellent, while only 63% percent were able to return to prior levels of play [48]. Many other studies have been published demonstrating a wide array of players that able to return back to prior levels. The return to play rates in overhead athletes have ranged from 22% to 71% with satisfaction levels being reported at around 69% [18, 25, 28, 49, 50]. When addressing unstable Type 2 SLAP tears, the surgeon must be cautious because it has been shown that placing an anchor anterior to the bicep anchor during SLAP repairs can results in decreased external rotation [51] which correlates with a failure to return to competition [52]. In 2011 Paletta et al demonstrated that all eight of their pitchers that lost greater than 10 degrees of external rotation at 90 degrees of shoulder abduction were unable to return to throwing [52]. Due to these findings, it is advocated that the labrum should be repaired only behind the bicep anchor in this population to prevent the loss of external rotation. In regards to management of the long head of the biceps tendon, primary bicep tenodesis is being increasingly chosen as a treatment of choice versus slap repair [53]. With the exception of Type 4 SLAP lesions, bicep tenodesis is not recommended in the young thrower population as the long head of the bicep tendon is thought to be a dynamic stabilizer and the placement of a drill hole in the proximal humerus creates a stress riser in an area subject to high torsional stress. In the senior author’s (DML) experience, surgery on the long head of the bicep tendon as treatment for SLAP induced pain is rarely necessary in this population. The number of tenodeses in professional pitchers is almost nonexistent (as per personal communication and MLB Team Physicians Association Meeting of 2016) due to the concern for stress risers. Tenotomy may be considered if the surgeon is convinced that the bicep tendon itself is the source of discomfort. However, routine tenodesis for treatment of shoulder pain in throwers with SLAP lesions noted on MRI would be gross overtreatment in the large majority of cases.

Once the labrum has healed, the principles applied during the non-operative program are again applied postoperatively. During the early post-operative phase, scapular posture is again reinforced and early passive external rotation in the scapular plane is instituted to avoid the critical loss of external rotation. Closed chain cuff exercises using “Ball on the Wall” or Dynamic Stabilization and Strengthening (DS2) platforms are safe and effective modalities to initiate early rotator cuff and scapula stabilization and strengthening.

Non-operative management is the standard for non-throwers as well. Focus on rotator cuff strengthening, scapular kinetics, and capsule flexibility is paramount to recovery. Determining the cause or etiology of the onset of symptoms either through the history or a physical exam can guide the target of the therapy. The physician, physical therapist, or athletic trainer must be cautious with increased or new activities as they can result in painful inflammation that impairs rotator cuff strength resulting in dynamic instability. If overuse induced inflammation is the primary cause of symptoms, anti-inflammatory modalities, medication such as non-steroidal anti-inflammatories or even steroids, and treatment as simple as cryotherapy geared to controlling inflammation are initiated followed by strengthening and training of scapular rhythm. Trauma such as a fall or motor vehicle accident can result in dysfunction of the rotator cuff resulting in a similar cascade, however, treatment should focus more on cuff strength and scapula kinetics in the early phase.