Internal impingement of the shoulder in the overhead athlete

Selective Activation of the Subscapularis Muscle: A Cross-Sectional Observational Study

BACKGROUND/OBJECTIVES

Clinicians have employed various therapeutic exercises to enhance the function and strength of the subscapularis muscle (SSC). However, few studies have investigated the most effective exercise for selectively activating the SSC while minimizing compensation from surrounding shoulder musculatures.

METHODS

Forty healthy participants without any shoulder complex conditions participated in this study. Individuals with a history of shoulder pain or musculoskeletal or neurological conditions affecting shoulder internal rotation were excluded. Participants performed three exercises: (1) Belly Press, (2) Lift Off, and (3) Prone Wiper, in a randomized order generated using Microsoft Excel. Ultrasound was then performed to assess the SSC and infraspinatus (IS) muscle thickness. Surface electromyography was used to record anterior deltoid (AD), pectoralis major (PM), and posterior deltoid (PD) muscle activity. Radiographic imaging was employed to evaluate the path of the instantaneous center of rotation (PICR). Data were analyzed using a one-way repeated-measures analysis of variance (ANOVA), followed by Bonferroni adjustment.

RESULTS

A significant reduction in IS thickness and PICR was observed only following the Belly Press (p < 0.05). Electromyographic activity of AD, PM, and PD increased significantly across all exercises (p < 0.05). These results demonstrate that the Belly Press most effectively allows the SSC to generate force while maintaining a stable center of rotation during shoulder movement.

CONCLUSIONS

The Belly Press was most effective in selectively activating the SSC while minimizing surrounding shoulder rotator muscle activity and reducing PICR. This finding may help clinicians identify and treat patients with shoulder internal rotation injuries.

A narrative review of little league shoulder: proximal humeral physis widening is only one piece of the puzzle, it is time to consider posterior glenoid dysplasia

Baseball athletes across all levels of play are at an increased risk for upper extremity injury due to the supraphysiologic demands on the shoulder and elbow during overhead throwing. Little league baseball players present with a unique subset of injuries that can affect the growth plate, commonly at the shoulder or the elbow. Ascertaining a diagnosis and plan of care for little league shoulder (LLS) historically focuses on the proximal humeral physis in skeletally immature throwing athletes presenting with shoulder pain. However, while not a current standard of care, posterior glenoid dysplasia is often present in youth baseball athletes presenting with LLS, warranting a shift in the way clinicians evaluate for and treat the youth baseball athlete's pathologic shoulder. Therefore, purpose of this narrative review is 2-fold: first, to describe the current standard of care as it relates to a diagnosis of LLS, and second, to critically describe a comprehensive evaluation process for youth throwing athletes with shoulder pain that includes screening for evidence of posterior glenoid dysplasia. This paper summarizes the current state of the available evidence for anatomic considerations of LLS in the baseball athletes throwing shoulder. Additionally, we provide a framework for clinical evaluation using a multidisciplinary approach to evaluate the entire kinetic chain of the youth baseball athlete presenting with LLS and posterior glenoid dysplasia. A case study is presented to describe common presentations, clinical and objective examinations, and a plan of care from time of evaluation to return to throwing.

Effects of modified sleeper stretch and modified cross-body stretch on upper limb functions and shoulder ROM in tennis players: a randomized trial

Tennis players often experience posterior shoulder pain due to restricted internal rotation (IR) range of motion (ROM) of the glenohumeral joint. No research has compared the effects of modified sleeper stretch (MSS) versus modified cross-body stretch (MCBS) on tennis players' upper limb functions and IR ROM. The study aimed to compare the efficacy of modified sleeper and cross-body adduction stretch in improving shoulder IR ROM and upper limb functions in tennis players. Thirty male lawn tennis players (aged 20 to 35 years) with more than 15° glenohumeral IR deficiency on the dominant side compared to the non-dominant side were recruited and divided into two groups: Modified sleeper stretch group (MSSG) and modified cross-body stretch group (MCBSG). MSSG received MSS, and MCBSG received MCBS, 3-5 repetitions once daily for 4 weeks. Upper limb functions were measured using the Disability of the Arm, Shoulder, and Hand (DASH) scale, and the IR ROM of the shoulder joint was measured using a universal goniometer. Both groups observed significant (p < 0.05) DASH scores and IR ROM improvements. DASH scores decreased by 85% in MSSG and 79.60% in MCBSG. IR ROM increased by 94.64% in MSSG and 89.52% in MCBSG. No significant differences (p > 0.05) were found in post-intervention DASH scores and IR ROM values between both groups. MSS and MCBS improved upper limb functions and IR ROM of the shoulder joint in the selected sample population of lawn tennis players. No difference was observed between both stretching techniques in improving upper limb functions and IR ROM of the shoulder joint.

Return to recreational sports participation following rotator cuff repair in adults over 40 Years of age: outcomes and return to play analysis

Background

Despite the high prevalence of rotator cuff (RTC) tears in older adults, there is limited literature evaluating the return to recreational sport after repair. The purpose of this study was (1) to assess the patient-reported outcomes and return to sport rates following rotator cuff repair in patients aged more than 40 years with minimum 2-year follow-up; (2) to compare baseline, preoperative and postoperative outcomes, and level of play following repair of self-reported athletes with nonathletes; and (3) to compare return to sport rates in overhead athletes compared to nonoverhead athletes.

Methods

Patients undergoing arthroscopic rotator cuff repair between January 2016 and January 2019 were screened for inclusion. Inclusion criteria included (1) age more than 40 years at the time of surgery, (2) arthroscopic repair of a full thickness RTC tear, and (3) preoperative American Shoulder and Elbow Surgeons score (ASES) available. Eligible patients were contacted and invited to fill out a custom return to sport and patient-reported outcome survey.

Results

Overall, 375 of the 1141 eligible patients completed the survey instrument. There were 210 self-reported athletes (mean age 59.2 ± 9.55 years) and 165 nonathletes (mean age 62.0 ± 8.27 years) (P = .003). Of the athletes, 193 (91.9%) returned to sport. The average age of athletes was 59.4 ± 9.33 years for those who returned to sport and 57.9 ± 12.0 years for those who did not (P = .631). Athletes reported higher ASES scores than nonathletes both preoperatively (49.8 ± 20.3 vs. 44.8 ± 18.9, P = .015) and postoperatively (87.6 ± 16.7 vs. 84.9 ± 17.5, P = .036), but there was no difference in mean ASES improvement between groups (37.7 ± 23.0 vs. 40.3 ± 24.5, P = .307). There was no difference in postoperative Single Assessment Numeric Evaluation scores when comparing self-reported athletes to nonathletes (85.4 ± 17.5 vs. 85.0 ± 18.7, P = .836). After controlling for age, sex, body mass index, and smoking status using a multivariate analysis, there was no difference in mean ASES improvement when comparing athletes to nonathletes.

Conclusion

There is a high rate of return to sport activities (> 90%) in older adult recreational athletes following arthroscopic repair of full thickness RTC tears and rates of return to sport did not significantly differ for overhead and nonoverhead athletes. Self-reported athletes were noted to have higher baseline, preoperative, and postoperative ASES scores than nonathletes, but the mean ASES improvement following repair did not significantly differ between groups.

Increased external rotation related to the soft tissues is associated with pathologic internal impingement in high-school baseball players

BACKGROUND

Changes in soft-tissue structures such as anterior laxity and posterior tightness are thought to contribute to the development of pathologic internal impingement in baseball players. Although side-to-side differences in shoulder rotational range of motion (ROM) is commonly used in clinical practice to quantify the soft-tissue changes, the ROM does not accurately reflect the soft-tissue changes because the ROM is affected not only by the soft tissues, but also by the bone. Increased retroversion of the humeral head is often observed in the dominant shoulder of throwing athletes. The purpose of this study was to determine the relationship between the soft-tissue-related (STR) ROM and pathologic internal impingement in baseball players.

METHODS

Bilateral humeral retroversion and ranges of glenohumeral external rotation (ER) and internal rotation (IR) were investigated in 81 high-school baseball players. The players were divided into two groups: the internal impingement group (19 players) and the control group (62 players). Humeral retroversion was measured using the ultrasound-assisted technique to assess the bone-related ER and IR. The STR ER and IR were defined as subtracting the amount of humeral retroversion from the measured ER and IR.

RESULTS

The side-to-side difference (throwing shoulder - nonthrowing shoulder) in humeral retroversion showed no significant difference between the internal impingement group (6° ± 10°) and control group (11° ± 11°) (P = .064). The side-to-side difference in STR ER was significantly greater in the internal impingement group (12° ± 12°) than that in the control group (1° ± 14°) (P = .002). No significant difference was observed in the side-to-side difference in STR IR between the internal impingement group (-7° ± 16°) and control group (-5° ± 15°) (P = .696). Pathologic internal impingement was significantly associated with the side-to-side difference of STR ER (odds ratio, 1.06 for increase of 1°; 95% confidence interval, 1.02-1.11; P = .008).

CONCLUSION

In high-school baseball players, the increased STR ER in the throwing shoulder may be associated with pathologic internal impingement. An increase of 10° in side-to-side difference in STR ER would increase the risk of pathologic internal impingement by 1.8 times.

Overview of Sport-Specific Injuries

Athletes are at risk for a variety of injuries not typically sustained in everyday life. The team physician must be capable of not only identifying and treating injuries as they occur, but he or she must be armed with the knowledge to minimize the risk of injuries before they occur. This review serves to provide an overview of the various sport-specific injuries typically encountered by team physicians. Injuries are grouped by body part and/or organ system, when possible. We do not aim to cover in detail the various treatments for these injuries; rather, we hope that this article provides a comprehensive overview of sport-specific injury, and demonstrate the well-roundedness in skills that must be possessed by team physicians.

A partial articular-sided supraspinatus tear caused by the biceps tendon: A novel etiology of internal impingement

Impingement of the LHB can directly lead to articular-sided supraspinatus tears. When pain persists despite arthroscopic debridement, we recommend taking the arm out of traction intraoperatively and placing it in the 90-90 position.

Management Options for Shoulder Impingement Syndrome in Athletes: Insights and Future Directions

Athletes participating in overhead sports are at particularly high risk of shoulder impingement syndrome. Subcoracoid impingement is defined as impingement of the anterior soft tissues of the shoulder between the coracoid process and the lesser tuberosity. Subacromial impingement syndrome (SIS) occurs due to extrinsic compression of the rotator cuff between the humeral head and coracoacromial structures or intrinsic degeneration of the supraspinatus tendon and subsequent superior migration of the humerus. Internal impingement is a major cause of shoulder pain in overhead athletes, and it occurs due to repetitive impingement of the articular surface of the rotator cuff with the glenoid during maximum abduction and external rotation of the arm. When examining athletes with suspected impingement of the shoulder, it is important to discuss the sport-specific motion that regenerates the symptoms and perform a combination of physical examination tests to improve the diagnostic accuracy. Radiographic evaluation is recommended, and the extent of soft tissue abnormalities can be assessed on ultrasound or magnetic resonance imaging of the shoulder. Management of shoulder impingement syndrome can be conservative or operative, based on the severity and chronicity of symptoms and the associated structural abnormalities. This review provides an update on the management of SIS, subcoracoid impingement, and internal impingement in the athletic population.

CORRELATION BETWEEN THE KERLAN-JOBE ORTHOPEDIC CLINIC SCREEN AND SUBACROMIAL IMPINGEMENT TEST-ITEM CLUSTER IN COLLEGIATE BASEBALL PITCHERS: A PILOT STUDY

Background

Shoulder injuries in baseball related to throwing account for 60% of all baseball injuries and 75% of those throwing injuries occur in pitchers. Impingement is the beginning of a continuum of rotator cuff pathology that can result in pain and disability in pitchers. Identification of self-reported measures and clinical tests that can indicate early pathology of shoulder impingement is needed for overhead athletes. Early identification of shoulder impingement is important to the long-term health and function of these athletes.

Hypothesis/Purpose

The purpose of this study was to determine if a correlation exists between self-reported pain and disability using the Kerlan-Jobe Orthopedic Clinic (KJOC) score and the Park Test-Item Cluster (TIC) for subacromial impingement in college baseball pitchers. The research hypotheses are that there will be a correlation 1) between the KJOC score and the TIC by Park and 2) between the KJOC and the Hawkins-Kennedy impingement, the painful arc, and the infraspinatus muscle strength tests individually.

Design

Cross-sectional pilot study.

Methods

Twenty-one collegiate baseball pitchers completed the KJOC and then were tested using the Park test-item cluster.

Data Analysis

Kruskal-Wallis was used to test the relationship of individual demographics with KJOC scores. Spearman rho correlation was used to determine if the number of positive clinical tests in the Park TIC or with the individual tests within the TIC correlated with scores on the KJOC.

Results

No significant relationships between KJOC scores and demographics were found. A significant moderate-to-good relationship was found between the painful arc test and the KJOC (r = -.601, p = 0.00) and a significant fair correlation was found between the number of positive tests within the Park TIC and KJOC (r = -.426, p = 0.05). No significant relationships were found between the Hawkins-Kennedy and KJOC (r = -.348, p = 0.12) or between the infraspinatus strength test and KJOC (r = -.040, p = 0.86).

Conclusion

The correlations between the painful arc test and the number of positive impingement tests with the composite score on the KJOC suggests a relationship between these two outcome measures, shoulder irritability, and decreased function in collegiate baseball pitchers. Of the three tests included in the Park TIC, the painful arc test was the only one with an independent significant correlation to the KJOC. The combination of impairment-specific cluster testing and an activity-focused self-assessment tool could be utilized to identify potential pathology and alert the medical professional that assessment and intervention are necessary.

Level of Evidence

Level 2 (Diagnosis).

Pediatric Sports Injuries

With increasing pediatric participation in organized sport and the early specialization of children in single sports, the number of injuries seen in the pediatric and adolescent athletic population continues to increase. Children experience acute traumatic injuries during practice and competition as well as chronic overuse injuries secondary to the repetitive stress on their developing bodies. The unique nature of the pediatric patient often requires a different diagnostic, prognostic, and treatment approach to sports injuries compared with their adult counterparts.

High incidence of posterior glenoid dysplasia of the shoulder in young baseball players

BACKGROUND

Rounding of the posterior glenoid rim is observed in young throwing athletes with internal shoulder impingement and is considered developmental dysplasia of the glenoid. The aim of our study was to determine the incidence rate of dysplastic changes of the glenoid within a group of 92 young baseball players.

METHODS

The study group included 92 male baseball players, with a mean age of 14.63 years. Of these patients, 30 were diagnosed with Little Leaguer's shoulder and 62 with a painful baseball-throwing shoulder with no abnormal findings on x-ray. The posterior glenoid rim of the affected shoulder was compared with the contralateral nonpainful shoulder, with the 2 following outcomes measured on radiographs obtained using the modified Bernageau imaging method: the distance between the anterior and posterior glenoid rims and the presence or absence of dysplasia of the posterior glenoid rim.

RESULTS

The mean distance between the anterior and posterior glenoid rims was significantly shorter in the painful shoulders (mean, 26 mm) than in the nonpainful shoulders (mean, 29 mm; P < .0001). Dysplasia of the posterior glenoid rim was identified in 89 painful shoulders (96.7%), with 9 cases (9.7%) identified on the unaffected contralateral side (P < .001). The presence of dysplasia was not correlated with the age at which baseball playing began.

CONCLUSION

The incidence of dysplasia of the posterior glenoid rim is high (96.7%) among young baseball players with a painful shoulder. The identified dysplasia may be related to impaired development of the inferior peripheral secondary glenoid ossification center due to repetitive throwing.

Rehabilitation of symptomatic atraumatic degenerative rotator cuff tears: A clinical commentary on assessment and management

STUDY DESIGN

Clinical Commentary.

INTRODUCTION

Atraumatic rotator cuff (RC) disease, is one of the most common cause of shoulder pain, which encompasses a continuum from tendinopathy to full thickness cuff tears. Extrinsic, intrinsic and environmental factors have been implicated in the pathophysiology of this disorder, affecting the clinical presentation of symptoms including pain and irritability. Successful rehabilitation of symptomatic atraumatic degenerative rotator cuff (SADRC) tears must address the underlying mechanisms causing dysfunction and correct modifiable factors.

PURPOSE OF THE STUDY

The purpose of this paper is to review the shoulder complex anatomy, introduce atraumatic degenerative RC pathology, differentiate between symptomatic and asymptomatic degenerative RC tears, propose an assessment and introduce the Rotator Cuff Protocol 1 (RCP1) designed by the clinical reasoning of one of the lead authors (LW) as a rehabilitation management approach for those clients who present with SADRC tears.

METHODS/RESULTS/DISCUSSION

N/A for clinical commentary.

CONCLUSIONS

The ability to identify SADRC tears should consider shoulder anatomy, extrinsic, intrinsic and environmental factors, and the consideration for the natural history of atraumatic partial and full thickness tears in the general population. A thorough clinical history and examination, which includes shoulder symptom modification tests, allows the examiner to determine at what phase the patient may start their exercise program. The RCP1 is a program that has been used clinically by many therapists and clients over the years and research is underway to test this protocol in atraumatic rotator cuff disease including SADRC tears.

LEVEL OF EVIDENCE

5.

Humeral Retroversion and Capsule Thickening in the Overhead Throwing Athlete: A Systematic Review

PURPOSE

To investigate the humeral and soft-tissue adaptations, including humeral retroversion, range of motion, and posterior capsule changes, in overhead throwing athletes.

METHODS

We performed a systematic review in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. PubMed, MEDLINE, CENTRAL (Cochrane Central Register of Controlled Trials), and Embase were searched from January 1, 2011, through April 23, 2017, by 2 reviewers independently and in duplicate. The methodologic quality of all included articles was assessed using the Methodological Index for Non-randomized Studies criteria. Interobserver agreement for assessments of eligibility was calculated with the Cohen κ statistic. Descriptive statistics and raw counts were used to summarize data.

RESULTS

We identified 14 studies (6 Level IV and 8 Level III) including 1,152 overhead throwing athletes. The mean age of the included athletes was 18.37 years (standard deviation, 1.52 years), with 59% of the athletes being pitchers and 41% being position players. Significantly greater humeral retroversion was found across all studies evaluating bony morphology in the dominant arm of overhead throwing athletes (range of mean differences, 9.6°-25.8°). Each of these studies also found decreased internal rotation in the dominant arm (range of mean internal rotation differences, -28° to -7.8°). Five studies found a significant negative correlation between the difference in humeral retroversion between the 2 arms and the difference in internal rotation (range of Pearson correlation coefficients, -0.56 to -0.35). Soft-tissue adaptations were assessed in 5 studies, with 4 identifying significantly thicker posterior capsules and 2 identifying significantly stiffer posterior capsules (P < .05).

CONCLUSIONS

Overhead throwing athletes consistently show several distinct changes in their dominant shoulder. These include increased humeral retroversion and the presence of a thickened and stiff posterior capsule. Concomitantly, there is often reduced internal rotation and increased external rotation of the dominant arm.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and IV studies.

Internal Impingement of the Shoulder: A Risk of False Positive Test Outcomes in External Impingement Tests?

Background

External impingement tests are considered as being particularly reliable for identifying subacromial and coracoid shoulder impingement mechanisms. The purpose of the present study was to evaluate if these tests are likely to provoke an internal shoulder impingement mechanism which, in cases of a pathologic condition, can lead to a positive test result.

Method

In 37 subjects, the mechanical contact between the glenoid rim and the rotator cuff (RC) was measured quantitatively and qualitatively in external impingement test positions using an open MRI system.

Results

Mechanical contact of the supraspinatus with the posterosuperior glenoid was present in 30 subjects in the Neer test. In the Hawkins test, the subscapularis was in contact with the anterosuperior glenoid in 33 subjects and the supraspinatus in 18. In the horizontal impingement test, anterosuperior contact of the supraspinatus with the glenoid was identified in 35 subjects.

Conclusion

The Neer, Hawkins, and horizontal impingement tests are likely to provoke the mechanism of an internal shoulder impingement. A posterosuperior internal impingement mechanism is being provoked predominately in the Neer test. The Hawkins test narrows the distance between the insertions of the subscapularis and supraspinatus and the anterosuperior labrum, which leads to an anterosuperior impingement mechanism.

Characteristics and Clinical Outcomes in Overhead Sports Athletes after Rotator Cuff Repair

Rotator cuff tears in young overhead sports athletes are rare. The pathomechanism causing rotator cuff tears in young overhead athletes is different from that in aged patients. The purpose of this study was to investigate rotator cuff tear characteristics in young overhead sports athletes to reveal the pathomechanism causing these injuries. This study included 25 overhead sports athletes less than 30 years old with atraumatic rotator cuff tears necessitating repair. Rotator cuff tear characteristics were evaluated intraoperatively, including rotator cuff tear shape and injured rotator cuff tendon. Clinical outcome measures were assessed before surgery and at the final follow-up. In this study, 22 patients reported minimal to no shoulder pain and returned to sports without significant complaints at last follow-up. The isolated infraspinatus tendon was most often injured; the incidence rate of the tear at this site was 32% (8 cases). In the deceleration phase of overhead motion, the eccentric contraction force of the ISP (infraspinatus) tendon peaks and the increased load leads to injury at the ISP tendon. The pathomechanism of rotator cuff injuries in young overhead athletes might be not only internal or subacromial impingement, but also these mechanisms.

Subpectoral Biceps Tenodesis for Tenosynovitis of the Long Head of the Biceps in Active Patients Younger Than 45 Years Old

PURPOSE

The objective of this study was to assess the outcomes after subpectoral biceps tenodesis (BT) for long head of the biceps (LHB) tenosynovitis in active patients <45 years old.

METHODS

This was an Institutional Review Board-approved, retrospective outcomes study with prospectively collected data. Patients treated with subpectoral BT were included if they met the following criteria: age <45 years, anterior shoulder pain with arthroscopically confirmed LHB tenosynovitis, no concomitant procedures other than debridement and decompression procedures, and minimum 2 years out from surgery. Patients were excluded from analysis if they refused participation. The American Shoulder and Elbow Surgeons (ASES), Short Form-12, Quick Disabilities of the Arm, Shoulder and Hand, Single Assessment Numeric Evaluation, and pain scores as well as sports participation preoperatively and at a minimum of 2 years postoperatively were obtained. Pre- and postoperative scores were compared using paired samples t-test and Wilcoxon signed-rank test.

RESULTS

Thirty patients met the inclusion criteria. Two of these patients refused to participate in follow-up and were excluded from analysis. Of the remaining 28 patients (17 male, 11 female; 37.0 ± 8.0 years), minimum 2-year outcomes were available for 24 (13 males, 11 females: 37.7 ± 8.2 years; 85.7%). Mean follow-up was 3.1 years (range, 2.0 to 7.3 years). There were significant improvements in all outcome measures including ASES score (P < .001), with a postoperative mean of 95.8 ± 7.8, visual analog scale "pain today" (P < .001), and pain affecting activities of daily living (P < .001). Seventeen of 20 (85%) patients who answered the question about postoperative sport participation were able to return to sport. Mean patient satisfaction was 9.2/10 (standard deviation, +1.7). There were no postoperative complications such as Popeye deformity or cramping. There were no clinical failures.

CONCLUSIONS

Subpectoral BT is an excellent treatment option for active patients <45 years old with LHB tenosynovitis and chronic anterior shoulder pain, resulting in decreased pain, improved function, high satisfaction, and improved quality of life.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Tendon vascularity in overhead athletes with subacromial pain syndrome and its correlation with the resting subacromial space

BACKGROUND

Supraspinatus tendinopathy is one of the common causes of subacromial pain syndrome (SAPS) in overhead athletes. Changes in tendon vascularity have been reported in painful tendons; however, the prevalence and distribution have not been investigated in young overhead athletes.

METHODS

We conducted a cross-sectional study of 47 overhead athletes (male, 31; female, 16) aged 18 to 36 years with SAPS for >3 months. A sonographer graded the severity of the tendinopathy and area of vascularization. Ultrasound imaging was used to measure supraspinatus tendon thickness, vascularity, and resting subacromial space. A self-written program was used to semiquantify the intensity of vascularity, expressed as the vascular index.

RESULTS

The majority (87.2%) of the participants had signs of tendinopathy in the supraspinatus tendon, and 40 (85.1%) of the tendinopathic tendons had vascularity. The majority (66.0%) of the vascularized subjects presented with minimal increase in vascularity, and 19.1% had moderate to severe vascularization. Most (79.2%) of the vascularization was observed in the pericortical region. The vascular index was negatively correlated with the resting subacromial space in male athletes with a reduced subacromial space (ρ = -0.63; P = .038).

CONCLUSION

Of overhead athletes with SAPS, 87.2% had supraspinatus tendinopathy with minimal to moderate vascularization, with the majority of vascularization occurring in the pericortical region. In male athletes with a reduced subacromial space, greater vascularity in the supraspinatus tendon was associated with a smaller resting subacromial space.

Evaluation and treatment of internal impingement of the shoulder in overhead athletes

One of the most common pathologic processes seen in overhead throwing athletes is posterior shoulder pain resulting from internal impingement. “Internal impingement” is a term used to describe a constellation of symptoms which result from the greater tuberosity of the humerus and the articular surface of the rotator cuff abutting the posterosuperior glenoid when the shoulder is in an abducted and externally rotated position. The pathophysiology in symptomatic internal impingement is multifactorial, involving physiologic shoulder remodeling, posterior capsular contracture, and scapular dyskinesis. Throwers with internal impingement may complain of shoulder stiffness or the need for a prolonged warm-up, decline in performance, or posterior shoulder pain. On physical examination, patients will demonstrate limited internal rotation and posterior shoulder pain with a posterior impingement test. Common imaging findings include the classic “Bennett lesion” on radiographs, as well as articular-sided partial rotator cuff tears and concomitant SLAP lesions. Mainstays of treatment include intense non-operative management focusing on rest and stretching protocols focusing on the posterior capsule. Operative management is variable depending on the exact pathology, but largely consists of rotator cuff debridement. Outcomes of operative treatment have been mixed, therefore intense non-operative treatment should remain the focus of treatment.

Trends in the Presentation, Management, and Outcomes of Little League Shoulder

BACKGROUND

With rising participation in youth sports such as baseball, proximal humeral epiphysiolysis, or Little League shoulder (LLS), is being seen with increasing frequency. However, there remains a paucity of literature regarding the causes, natural history, or treatment outcomes of LLS.

PURPOSE

To analyze the demographic, clinical, and diagnostic features of a population of LLS patients, with an emphasis on identifying underlying risk factors for the development and recurrence of LLS after nonoperative treatment.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A departmental database at a high-volume regional children's hospital was queried to identify cases of LLS between 1999 and 2013. Medical records were reviewed to allow for analysis of age, sex, athletic information, physical examination and radiologic findings, treatment details, clinical course, and rates of recurrence.

RESULTS

Ninety-five patients (93 males, 2 females; mean age, 13.1 years; range, 8-16 years) were diagnosed with LLS. The number of diagnosed cases increased annually over the study period. All patients had shoulder pain with overhead athletics; secondary symptoms included elbow pain in 13%, shoulder fatigue or weakness in 10%, and mechanical symptoms in 8%. While the majority of patients (97%) were baseball players (86% pitchers, 8% catchers, 7% other positions), a small subset (3%) were tennis players. On physical examination, 30% were reported to have glenohumeral internal rotation deficit (GIRD), defined as a decreased arc of rotational range of motion of the shoulder. Treatment recommendations included rest in 99% of cases, physical therapy in 79% (including 100% of patients with GIRD), and position change upon return to play in 26%. Average time to full resolution of symptoms was 2.6 months, while average time to return to competition was 4.2 months. Recurrent symptoms were reported in 7% of the overall cohort at a mean of 7.6 months after initial diagnosis. The odds of recurrence in the group with diagnosed GIRD (14%) were 3.6 times greater than those without GIRD (5%; 95% CI: 0.7-17.1), but this difference was not statistically significant (P = .11).

CONCLUSION

Little League shoulder is being diagnosed with increasing frequency. While most common in male baseball pitchers, the condition can occur in females, youth catchers, other baseball positions players, and tennis players. Concomitant elbow pain may be seen in up to 13%. After rest and physical therapy, recurrent symptoms may occur in a small subset of patients (7%), generally 3 to 6 months after return to sports. Almost one-third of LLS patients had GIRD, and this group had approximately three times higher probability of recurrence compared with those without GIRD.

Superior labral anterior posterior lesions of the shoulder: Current diagnostic and therapeutic standards

Surgical treatment of superior labral anterior posterior (SLAP) lesion becomes more and more frequent which is the consequence of evolving progress in both, imaging and surgical technique as well as implants. The first classification of SLAP lesions was described in 1990, a subdivision in four types existed. The rising comprehension of pathology and pathophysiology in SLAP lesions contributed to increase the types in SLAP classification to ten. Concerning the causative mechanism of SLAP lesions, acute trauma has to be differed from chronic degeneration. Overhead athletes tend to develop a glenohumeral internal rotation deficit which forms the basis for two controversial discussed potential mechanisms of pathophysiology in SLAP lesions: Internal impingement and peel-back mechanism. Clinical examination often remains unspecific whereas soft tissue imaging such as direct or indirect magnetic resonance arthrography has technically improved and is regarded to be indispensable in detection of SLAP lesions. Concomitant pathologies as Bankart lesions, rotator cuff tears or perilabral cysts should be taken into consideration when planning a personalized therapeutic strategy. In addition, normal variants such as sublabral recess, sublabral hole, Buford complex and other less common variants have to be distinguished. The most frequent SLAP type II needs a sophisticated approach when surgical teatment comes into consideration. While SLAP repair is considered to be the standard operative option, overhead athletes benefit from a biceps tenodesis because improved patient-reported satisfaction and higher rate of return to pre-injury level of sports has been reported.

Traumatic Supraspinatus Tears in Patients Younger Than 25 Years

Traumatic rotator cuff tears in patients younger than 25 years are rare events, with few reports in the literature. When compared with the more mature shoulder, the young, healthy supraspinatus tendon is a robust tendon that is able to absorb a significant amount of energy before tendon failure. Therefore, the diagnosis of a rotator cuff tear can be often overlooked in this population due to the patient's age. This is a report of traumatic supraspinatus repairs in patients younger than 25 years. Nine patients younger than 25 years were identified with a posttraumatic supraspinatus tear as visualized during routine diagnostic shoulder arthroscopy. These 9 patients represented 0.33% of all rotator cuff repairs during a 9-year period. Average patient age was 19.1 years (±3.7 years; range, 13 to 25 years). Magnetic resonance imaging failed to diagnose a rotator cuff tear in 50% of the patients. Mean delay from injury to surgery was 6.6 months. All tears were arthroscopically repaired. Concomitant anterior instability pathology was demonstrated among 66.7% of the patients. No complications were reported. At latest follow-up, all patients reported minimal to no shoulder pain and were tolerating strenuous work, activities, and sports without significant complaints. Even with advanced imaging, the diagnosis of a rotator cuff tear can often be missed in this patient population. Although clinical outcomes can be good, care must be taken to broaden the diagnostic differential in young patients with posttraumatic shoulder pain.

Anterior shoulder capsular tears in professional baseball players

BACKGROUND

Tearing of the anterior capsule of the shoulder is a rare but debilitating injury for throwing athletes. However, there is very little in the literature to guide its diagnosis and treatment. In this case series, we outline our experience with anterior capsular tears of the shoulder in professional baseball players.

METHODS

Five professional baseball players were diagnosed with midsubstance tears of their anterior capsule. A trial of rest and rehabilitation failed in all patients, and they eventually underwent surgery. These patients were retrospectively reviewed. The presenting symptoms and findings were documented, and outcomes were assessed by the player's ability to return to play.

RESULTS

The mean age was 33.5 years (range, 31-37 years), and all patients presented with anterior shoulder pain and the inability to throw. No patient had an acute traumatic injury. Magnetic resonance imaging provided the correct diagnosis in 4 patients, and the diagnosis was made with diagnostic arthroscopy in the fifth. Three underwent arthroscopic repair, and 2 underwent open repair of the anterior capsule. Of the 5 players, 4 (80%) returned to their preinjury level by a mean of 13.3 months (range, 8-18 months).

CONCLUSIONS

Anterior capsular tears can occur in older throwing athletes. Surgical repair, whether arthroscopic or open, can yield good results in most patients.

[The throwing shoulder]

BACKGROUND

During the throwing motion high forces are placed on the athlete's shoulder and extreme positions of external rotation and abduction are reached. The dynamic and static stabilizers of the glenohumeral joint need to handle a delicate balance between shoulder mobility and stability.

CAUSES OF INJURY

Repetitive forces lead to adaptive osseous, capsular, ligament and muscular changes. This should increase external rotation of the shoulder and thus initially help to improve performance but ultimately could cause shoulder pathologies. For instance, tissue overuse can result in muscular imbalance, functional instability and posterior capsular contracture with the development of a glenohumeral internal rotation deficit.

INJURY PATTERNS

An internal impingement is often observed in throwing athletes which can be subdivided into the more common posterosuperior type and the rarer anterosuperior type. Typical lesions in the throwing shoulder are articular-sided partial rotator cuff tears, labrum and biceps tendon lesions and edema, cysts or osteochondral lesions of the humeral head or glenoid.

DIAGNOSTICS

For an accurate diagnosis it is important to include the history, a thorough physical examination and magnetic resonance arthrography. The correlation of clinical examination and imaging is critical to identify symptomatic lesions.

THERAPY

If conservative therapy fails or in cases of significant structural damage resulting in clinical symptoms, surgical treatment should be considered based on the underlying pathology and carried out using established techniques and criteria.

Axillary artery thrombosis in a major league baseball pitcher: a case report and rehabilitation guide

This case study describes a Major League Baseball player who was diagnosed with an axillary artery thrombosis due to arterial compression from throwing. The purpose of this article is to create awareness as to the signs and symptoms associated with arterial positional compression and the rehabilitative implications to surgical intervention.

The primer for sports medicine professionals on imaging: the shoulder

Because of its inherent superior soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging (MRI) is highly suited to study the complex anatomy of the shoulder joint, particularly when assessing the relatively high incidence of shoulder injuries in young, athletic patients. This review aims to serve as a primer for understanding shoulder MRI in an algorithmical approach, including MRI protocol and technique, normal anatomy and anatomical variations of the shoulder, pathologic conditions of the rotator cuff tendons and muscles, the long head of the biceps tendon, shoulder impingement, labral and glenohumeral ligament pathology, MR findings in shoulder instability, adhesive capsulitis, and osteoarthritis.

Anterior glenohumeral laxity and stiffness after a shoulder-strengthening program in collegiate cheerleaders

CONTEXT

Approximately 62% of all cheerleaders sustain some type of orthopaedic injury during their cheerleading careers. Furthermore, the occurrence of such injuries has led to inquiry regarding optimal prevention techniques. One possible cause of these injuries may be related to inadequate conditioning in cheerleaders.

OBJECTIVE

To determine whether a strength and conditioning program produces quantifiable improvements in anterior glenohumeral (GH) laxity and stiffness.

DESIGN

Descriptive laboratory study.

SETTING

University laboratory.

PATIENTS OR OTHER PARTICIPANTS

A sample of 41 collegiate cheerleaders (24 experimental and 17 control participants) volunteered. No participants had a recent history (in the past 6 months) of upper extremity injury or any history of upper extremity surgery.

INTERVENTION(S)

The experimental group completed a 6-week strength and conditioning program between the pretest and posttest measurements; the control group did not perform any strength training between tests.

MAIN OUTCOME MEASURE(S)

We measured anterior GH laxity and stiffness with an instrumented arthrometer. We conducted a group × time analysis of variance with repeated measures on time (P < .05) to determine differences between groups.

RESULTS

A significant interaction was demonstrated, with the control group having more anterior GH laxity at the posttest session than the strengthening group (P = .03, partial η2 = 0.11). However, no main effect for time (P = .92) or group (P = .97) was observed. In another significant interaction, the control group had less anterior GH stiffness at the posttest session than the strengthening group (P = .03, partial η2 = 0.12). Main effects for time (P = .02) and group (P = .004) were also significant.

CONCLUSIONS

Cheerleaders who participate in a shoulder-strengthening program developed less anterior GH laxity and more stiffness than cheerleaders in the control group.

The disabled throwing shoulder: spectrum of pathology-10-year update

In the 10 years since the current concept series entitled "The Disabled Throwing Shoulder: Spectrum of Pathology" was conceived and written, many studies have been reported that add much more information to the understanding of the disabled throwing shoulder (DTS). The editors of Arthroscopy and the authors of the original series believed that an update to the original series would be beneficial to provide an organized overview of current knowledge that could update the thought process regarding this problem, provide better assessment and treatment guidelines, and guide further research. A dedicated meeting, including current published researchers and experienced clinicians in this subject, was organized by the Shoulder Center of Kentucky. The meeting was organized around 5 areas of the DTS that were highlighted in the original series and appear to be key in creating the DTS spectrum and to understanding and treating the DTS: (1) the role of the kinetic chain; (2) the role and clinical evaluation of the scapula; (3) the role of deficits in glenohumeral rotation, glenohumeral internal rotation deficit, and total range-of-motion deficit in the causation of labral injury and DTS; (4) the role of superior labral (SLAP) injuries and rotator cuff injuries; and (5) the composition and progression of rehabilitation protocols for functional restoration of the DTS. The meeting consisted of presentations within each area, followed by discussions, and resulted in summaries regarding what is known in each area, what is not known but thought to be important, and strategies to implement and enlarge the knowledge base.

A comparison of glenoid morphology and glenohumeral range of motion between professional baseball pitchers with and without a history of SLAP repair

PURPOSE

We sought to examine the relation among glenoid morphology, glenohumeral range of motion (ROM), and history of shoulder injury in professional baseball pitchers.

METHODS

We studied 58 professional baseball pitchers. Internal rotation (IR) and external rotation (ER) ROM was measured at 90° of abduction. Horizontal adduction (HAdd) ROM was also measured. Glenoid superior inclination and glenoid retroversion (GRV) were then measured radiographically. Separate mixed-model analyses of variance were used to compare dependent measures between the dominant and nondominant shoulders of pitchers with or without a history of SLAP repair. Significant interaction effects were interpreted by use of a test for simple main effects (α = .05).

RESULTS

GRV was significantly greater on the dominant side (8.7° ± 5.6°) versus nondominant side (5.5° ± 5.2°) (P = .001), whereas glenoid superior inclination was equivalent (99.5° ± 4.3° for dominant side v 99.2° ± 4.4° for nondominant side, P = .853). Post hoc analysis indicated that pitchers with a history of SLAP repair did not display an adaptive increase in dominant GRV compared with nondominant GRV (P = .016). There were no statistical differences between groups for ER (P = .29), IR (P = .39), or HAdd (P = .39). The dominant shoulder displayed greater ER (mean increase, 6.2° ± 12.2°) with a complementary decrease in IR (mean decrease, 5.8° ± 13.2°) and HAdd (mean decrease, 8.9° ± 13.7°) compared with the nondominant side.

CONCLUSIONS

Our findings suggest that the development of increased GRV in the dominant shoulder of professional baseball pitchers may be a protective adaptive change not reflected in glenohumeral ROM measures.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Passive range of motion characteristics in the overhead baseball pitcher and their implications for rehabilitation

BACKGROUND

Repetitive overhead throwing motion causes motion adaptations at the glenohumeral joint that cause injury, decrease performance, and affect throwing mechanics. It is essential to define the typical range of motion (ROM) exhibited at the glenohumeral joint in the overhead thrower.

QUESTIONS/PURPOSES

We (1) assessed the glenohumeral joint passive range of motion (PROM) characteristics in professional baseball pitchers; and (2) applied these findings clinically in a treatment program to restore normal PROM and assist in injury prevention.

METHODS

From 2005 to 2010, we evaluated 369 professional baseball pitchers to assess ROM parameters, including bilateral passive shoulder external rotation (ER) at 45° of abduction, external and internal rotation (IR) at 90° abduction while in the scapular plane, and supine horizontal adduction.

RESULTS

The mean ER was greater for the throwing and nonthrowing shoulders at 45° of abduction, 102° and 98°, respectively. The throwing shoulder ER at 90° of abduction was 132° compared with 127° on the nonthrowing shoulder. Also, the pitcher's dominant IR PROM was 52° compared with 63° on the nondominant side. We found no statistically significant differences in total rotational motion between the sides.

CONCLUSIONS

Although we found side-to-side differences for rotational ROM and horizontal adduction, the total rotational ROM was similar.

CLINICAL RELEVANCE

The clinician can use these PROM values, assessment techniques, and treatment guidelines to accurately examine and develop a treatment program for the overhead-throwing athlete.

Radiocapitellar cartilage injuries associated with tennis elbow syndrome

PURPOSE

A recent anatomical study has suggested that considerable contact between the undersurface of the extensor carpi radialis brevis (ECRB) and the lateral edge of the capitellum is the cause of tendon injury in lateral epicondylosis. We hypothesized that this contact might concurrently induce cartilage injuries of the capitellum. The purpose of the present study was to determine the prevalence, location, and severity of cartilage lesions of the radiocapitellar joint accompanying lateral epicondylosis and to identify their correlation with ECRB status.

METHODS

Arthroscopic assessment of the articular cartilage was performed for 31 elbows in 31 patients with lateral epicondylosis who had surgery. The study group consisted of 18 women and 13 men with a mean age of 50 years (range, 35 to 67 y). The relationship between the presence of the cartilage lesions and patient demographics, preoperative pain visual analog scale score, number of cortisone injections, and surgical findings including ECRB tears were investigated.

RESULTS

Cartilage injuries of the capitellum were found in 20 (65%) and cartilage injuries of the radial head were found in 25 (81%) of 31 elbows. Most of the lesions were located on the lateral aspect of the capitellum and radial head. Multivariate logistic regression analysis revealed that the absence of ECRB tears was independently associated with a higher risk of cartilage injuries of the capitellum.

CONCLUSIONS

Cartilage injury was frequently found in the lateral edge of the capitellum and radial head. Lesions of the capitellum were related to the absence of ECRB tears.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Superior labral anteroposterior lesions of the shoulder: part 2, mechanisms and classification

OBJECTIVE

The objectives of this article are to discuss the 10 distinct patterns of superior labral anteroposterior (SLAP) tears to facilitate adequate diagnosis and treatment. Correlations with clinical presentation, mechanism of injury, and treatment will enhance understanding.

CONCLUSION

Imaging plays an important role in the diagnosis of SLAP tears. Knowledge of glenolabral anatomy, related structures and variants, proper imaging techniques, and a systematic approach to MRI interpretation is important in the diagnosis and treatment planning of the 10 types of SLAP lesions. Arthroscopy offers a means for definitive diagnosis.

Shoulder pain in the adolescent athlete: a multidisciplinary diagnostic approach from the medical, surgical, and imaging perspectives

This article is a compilation work authored by a pediatric radiologist, primary care pediatric sports medicine physician and pediatric orthopedic surgeon with the goal of providing a simplified diagnostic approach to the adolescent athlete presenting with shoulder pain. The spectrum of complex diagnoses often confused by innumerable radiologic acronyms can be distilled into common recognizable injury patterns. Once the physiology leading to the injury pattern is understood, the pediatric radiologist can perform a more focused imaging approach and provide a more meaningful interpretation to the referring orthopedic specialist.