Commentary - Archives of Orthopaedics (2020) Volume 1, Issue 1
Editorial Commentary for In Throwers with Posterior Instability, Rotator Cuff Tears are Common but Do Not Affect Surgical Outcomes
Andrew J. Sheean1*, James P. Bradley2
1Department of Orthopaedic Surgery, San Antonio Military Medical Center, San Antonio, TX, USA
2University of Pittsburgh Medical Center; Burke and Bradley Orthopedics, Pittsburgh, PA, USA
- *Corresponding Author:
- Andrew Sheean
Received date: May 15, 2020; Accepted date: June 08, 2020
Citation: Sheean AJ, Bradley JP. Editorial Commentary for In Throwers with Posterior Instability, Rotator Cuff Tears are
Common but Do Not Affect Surgical Outcomes. Arch Orthop. 2020; 1(1): 14-16.
Copyright: © 2020 Sheean AJ, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Superior labral pathology is an exceedingly common entity among throwers, and in recent years, a number of reports have elucidated the prevalence of posterior glenohumeral instability among overhead athletes (baseball, softball, volleyball.) However, within this unique patient population, these conditions should not be viewed as separate clinical entities, but, rather as findings that exist on a single pathomechanic spectrum. In 2020, we now know that the complexity of the symptomatic thrower’s shoulder is a consequence of the complex anatomic relationships between the biceps tendon, capsulolabral tissues, posterosuperior rotator cuff, and the glenoid. In 2003, Burkhart et al. noted that diminished glenohumeral range of motion (i.e. glenohumeral internal rotation deficit “GIRD”) was common among throwers with painful shoulders. These authors further described a posterior-inferior capsular contracture as the “essential lesion” in the development of diminished range of motion in conjunction with impingement of the supraspinatus tendon between the greater tuberosity and the posterior-superior labrum (“pathologic internal impingement”) [1,2]. It is this internal impingement that so often manifests as partial thickness, articular sided supraspinatus tears in the throwing athlete. But these findings are now perhaps better understood as sequelae of a number of anatomic factors, including humeral retrotorsion, contractures of the coracohumeral ligament, pectoralis, and anterior deltoid, as well as dynamic muscle stiffness that can occur in response to the repetitive strains involved in overhead throwing.
The labrum does not have a consistent anatomy around the entire glenoid face, as the superior labrum is more loosely attached to the glenoid margin, and, consequently, is more mobile throughout the range of motion during overhead activities . Conversely, the inferior labrum, is well attached to the glenoid margin and relatively immobile. These zone-specific, anatomic variations have important implications for glenohumeral mechanics during the throwing cycle. As long as the superior labrum is capable of maintaining its function as an adequate tension band linked to an intact inferior labrum, some degree of superior labral detachment may actually be beneficial in order to facilitate maximum cocking during the throwing cycle . This fact likely explains why asymptomatic throwers are so commonly found to have SLAP lesions on MRI . However, the throwing shoulder can become symptomatic when a labral tear extends from the biceps anchor into the posterior band of the inferior glenohumeral ligament (PIGHL.) Oftentimes, the progression of this pathology in an inferior direction leads to flattening of the labrum and/or an intrasubstance delamination. The result is an ensuing pathologic cascade, as the tension band becomes incompetent, decreasing both the capsulolabral bumper effect of the labrum inferior and the tension in the PIGHL. Posterior instability during overhead throwing is the end result of this process.
Despite the growing body of literature pertaining to posterior glenohumeral instability, there remains a relative paucity of results specific to overhead throwing athletes and even less has been written about the outcomes of posterior labral repairs when performed in conjunction with partial thickness rotator cuff tears. The preponderance of current information suggests that throwers remain a difficult group of patients to treat when it comes to returning them to their pre-injury
level of performance. Several recently published reports
have suggested that throwers, particularly pitchers,
undergoing posterior stabilization procedures are able to
return to sport, although return to their pre-injury level
of performance is less commonly observed. McClincy et
al. performed a review of 48 overhead throwing athletes
(18 pitchers, 38%), matching this cohort to non-throwing
athletes that underwent arthroscopic posterior labral
repair. These authors observed no significant differences
in patient reported outcomes between groups were
observed at a mean follow-up of 37 months (range: 12 to
97 months.) However, only 60% of throwers were able to
return to their pre-injury level of competitive throwing,
with only 50% of pitchers were able to return to their
pre-injury level of competitive throwing . Fourman et
al. published the largest series to date related to clinical
outcomes following arthroscopic Type VIII SLAP (superior
labrum anterior posterior tears extending inferiorly into
the PIGHL) repair in 46 patients (27 throwers, 19 nonthrowers),
noting significant improvements in functional
outcomes were observed throughout the entire cohort
(mean age: 24.2 ± 9.2 years.) Once again, however,
throwers reported more pain, decreased range of motion,
and lower Kerlan Jobe Orthopaedic Clinic (KJOC) scores
when compared to non-throwers . Most recently,
Kercher et al. reported on 32 baseball players with a
mean follow-up of 41.6 months (range: 24-92 months.)
These authors noted that 94% of players were able
to return to sport, but again, only 61% of players were
able to return to the previous level of play . Taken
together, these studies illustrate two important points.
First, posterior instability is a commonly observed in the
setting of superior labral pathology, and when evaluating
these patients, consideration should always be paid to
the possibility (and likelihood) of combined superior
and posterior labral lesions. Second, when treating
these athletes surgically, one must differentiate return
to play from pre-injury level of performance. The former
is generally achieved, while the latter is less reliably
achieved. This is a critical distinction that should be
made and used in order to temper athletes’ expectations
regarding the implications of surgical intervention on
The spectrum of these injuries commonly involves partial thickness, articular sided rotator cuff tears, however, we are aware of only one series published specifically on the surgical outcomes associated with posterior instability and concomitant rotator cuff tears. In 2018, Arner et al. reported on the clinical outcomes of 56 throwing athletes undergoing posterior labral repair . Twentyfour athletes were noted to have concomitant rotator cuff
pathology, while 32 athletes were found to have isolated
posterior labral tears. All rotator cuff tears were found
to encompass less than 50% tendon thickness, and all
rotator cuff tears were treated with debridement alone.
Mean postoperative American Shoulder Elbow Society
(ASES) scores improved significantly in both groups.
Similarly, post-operative pain, instability, and functional
scores all improved in both groups. Additionally, these
authors did not observe significant differences between
those athletes with and without rotator cuff pathology in
any of the reported outcome measures. However, similar
to the previously reviewed studies, the authors noted
a substantial discrepancy between return to play and
return to pre-injury level of performance in the cohort
with combined posterior instability and partial articular
sided rotator cuff tears: 22 of 24 (92%) athletes returning
to sport, but only 16/24 (67%) returning to their same
level of performance. And while the rotator cuff tears in
this series were treated with a limited debridement, a
recently published systematic review on return to sport
rates among competitive athletes undergoing rotator
cuff repair underscores the more general challenges
associated with treating this unique patient population.
Among the 15 studies including 347 overhead athletes (81
competitive and 266 recreational), 61.5% of competitive
athletes were able to return to their same level of play or
Intra-articular lesions commonly observed in the thrower’s shoulder with posterior instability exist on a spectrum, and effective surgical management necessitates an understanding of a well-described pathomechanic process. Partial articular sided rotator cuff tears are frequently observed, and a limited debridement of these lesions remains the mainstay of treatment. Returning these athletes to their pre-injury level of play remains a challenging proposition. Surgeons must acknowledge these facts and beware of their implications on athletic performance among this unique patient population. Future efforts should be devoted towards improving diagnostic modalities and expanding clinical studies focused on examining the efficacy of biologic adjuncts in the treatment of posterior glenohumeral instability.
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