Current Concepts in the Assessment and Rehabilitation of the Thrower’s Shoulder

Electromyographic analysis of shoulder-complex muscles performing overhead presses with dumbbell, kettlebell, and bottom-up kettlebell

INTRODUCTION

Kettlebell exercises, specifically the bottom-up grip, have become increasingly popular in training programs. The purpose of this research was to determine if a bottom-up kettlebell grip favorably alters the electromyography (EMG), activity in the medial deltoid (MD), serratus anterior (SA), and lower trapezius (LT), muscles compared to using a dumbbell or traditional kettlebell grip during overhead shoulder presses.

METHODS

Twenty-eight healthy, male, Division III collegiate baseball players (mean age = 19.8 ± 1.28 years) performed five overhead presses of equal weight, 11.34 kg (25 lbs), using a dumbbell (DB), kettlebell w/traditional grip (KB), and kettlebell held with a bottom-up grip (KBU).

RESULTS

For the MD, there was significantly greater EMG activity using the DB compared to KBU, but no significant differences between the DB and KB, or KB and KBU. For the SA, greater EMG activity was noted using the KBU compared to KB, and KBU compared to DB, but no differences between KB and DB. For the LT, greater EMG activity was noted using the DB compared to KB, but no differences between DB and KBU, or KB and KBU.

CONCLUSION

The KBU press only elicited greater EMG activity in the SA. The DB elicited greater EMG activity in both the MD and LT. Shoulder-complex EMG activity varies with different types of overhead presses using equivalent loads.

Physical therapy management of an athlete with a Kim lesion using physical agents, manual therapy, and therapeutic exercise: a case report

BACKGROUND

Several operative procedures have been described for treating a Kim lesion. However, no physical therapy intervention has been documented as conservative treatment for these cases.

OBJECTIVE

The purpose of this report was to describe a physical therapy management protocol for an athlete with a Kim lesion.

CASE DESCRIPTION

A 22-year-old female volleyball athlete presented to physical therapy with an 8-month history of right shoulder pain when performing the serve and attack sports gestures. Pain was 5/10 on the visual analogue scale (VAS). Pain was localized along the glenohumeral joint, around the long head of the biceps brachii tendon, and at the subscapularis tendon insertion. Shoulder range of motion (ROM) was limited to flexion (150°), abduction (158°), and internal rotation (80°). Kim lesion was confirmed by clinical tests (Kim test and Jerk test) and via magnetic resonance imaging. Shoulder functional outcomes were verified through the University of California Los Angeles (UCLA) shoulder rating scale. Upper extremity sensorimotor control was verified in bimanual support by stabilometry on a baropodometer. Core function was assessed through a plank test and a side plank test. The 8-week course of treatment included manual therapy, physical agents, shoulder and scapular mobilizations, resistance and sensorimotor exercises, core strengthening, and functional exercises.

OUTCOMES

Physical therapy interventions resulted in a decrease in VAS pain (3/10), an increase in shoulder ROM (10.8°) and in UCLA shoulder score (from 22 to 33 points), a reduction in the center of pressure displacement (27-56%), and an increase in plank test (45%) and side plank test (21-29%) performance. The athlete had a full return to sport after the treatment.

CONCLUSION

We concluded that the protocol used for conservative management of Kim lesion resulted in clinical satisfactory physical and functional outcomes for the athlete.

Relationship between scapular control during isometric shoulder flexion and scapular motion during baseball pitching: a cross-sectional study

Background

A baseball pitcher with decreased scapular control may not be able to achieve suitable scapular motion at maximum shoulder external rotation (MER) of baseball pitching during the pitching action. It is common clinically to compare scapular control of the throwing and non-throwing arms to detect side-to-side differences. However, it remains unclear whether scapular control is different between the throwing and non-throwing arms. Moreover, no data exist on the relationship between scapular control and scapular motion at MER of pitching. Primarily, this study aimed to compare scapular control during isometric shoulder flexion between the throwing and non-throwing arms. Secondly, this study aimed to investigate the relationship between scapular control during isometric shoulder flexion and scapular motion at MER of pitching.

Methods

Fifteen healthy collegiate baseball pitchers (age, 20.2 ± 1.9 years; height, 1.76 ± 0.05 m; body mass, 73.3 ± 6.7 kg) were recruited. An optical motion tracking system was used to assess scapular motion. Scapular control was defined as the amount of change in the scapular internal rotation angle, downward rotation angle, and anterior tilt angle during isometric shoulder flexion. We assessed scapular position at MER of pitching.

Results

No significant differences were detected for any of the scapular angles during isometric shoulder flexion between the throwing and non-throwing arms. The amount of change in the scapular internal rotation angle, scapular downward rotation angle, and scapular anterior tilt angle during isometric shoulder flexion had a significant relationship with the scapular downward rotation angle at MER.

Conclusions

No side-to-side difference was noted in scapular control during isometric shoulder flexion in healthy collegiate baseball pitchers at the group level. Further studies are required to understand the side-to-side differences at the individual level. Additionally, there was a relationship between scapular control during isometric shoulder flexion and scapular position at MER. These findings suggest that clinicians may consider using isometric shoulder flexion to assess scapular control in baseball pitchers.

Rotator Cuff Injuries in Tennis Players

PURPOSE OF REVIEW

This review presents epidemiology, etiology, management, and surgical outcomes of rotator cuff injuries in tennis players.

RECENT FINDINGS

Rotator cuff injuries in tennis players are usually progressive overuse injuries ranging from partial-thickness articular- or bursal-sided tears to full-thickness tears. Most injuries are partial-thickness articular-sided tears, while full-thickness tears tend to occur in older-aged players. The serve is the most energy-demanding motion in the sport, and it accounts for 45 to 60% of all strokes performed in a tennis match, putting the shoulder at increased risk of overuse injury and rotator cuff tears. Studies have shown deficits in shoulder range of motion and scapular dyskinesia to occur even acutely after a tennis match. First-line treatment for rotator cuff injuries in any overhead athlete consists of conservative non-operative management with appropriate rest, anti-inflammatory drugs, followed by a specific rehabilitation program. Operative treatment is usually reserved for older-aged players and to those who fail to return to play after conservative measures. Surgical options include rotator cuff debridement with or without tendon repair, biceps tenodesis, and labral procedures. Unlike rotator cuff repairs in the general population, repairs in the elite tennis athlete have less than ideal rates of return to sport to the same level of performance. Rotator cuff injuries are a common cause of pain and dysfunction in tennis players and other overhead athletes. The etiology of rotator cuff tears in tennis players is multifactorial and usually results from microtrauma and internal impingement in the younger athlete leading to partial tearing and degenerative full-thickness tears in older players. Surgical treatment is pursued in athletes who are still symptomatic despite an extensive course of non-operative treatment as outcomes with regard to returning to sport to the same pre-injury level are modest at best. Debridement alone is usually preferred over rotator cuff repairs for partial tears in younger players due to potential over-constraining of the shoulder joint and decreased rates of return to sport after rotator cuff repairs.

Internal impingement of the shoulder in overhead athletes: Retrospective multicentre study in 135 arthroscopically-treated patients

BACKGROUND

Internal impingement of the shoulder (IIS) is the leading cause of chronic shoulder pain in overhead throwing athletes. No consensus exists about which techniques are optimal when surgery is in order. The available studies are limited by small sample sizes and short follow-ups. The primary objective of this study was to assess return-to-sports (RtS) outcomes after surgical treatment for IIS. A favourable RtS outcome (RtS+) was defined as returning to the previous sport at the same or a higher level.

HYPOTHESIS

The main hypothesis was that surgical treatment resulted in an RtS+ outcome. The secondary hypothesis was that epidemiological factors, pre- and intra-operative anatomical factors, and specific surgical procedures were associated with higher RtS+ rates.

MATERIAL AND METHODS

A retrospective multicentre design was used. We included 135 patients with IIS managed arthroscopically using any of the following procedures: anterior capsulorrhaphy, posterior capsulotomy/capsulectomy, postero-superior labral debridement, posterior glenoidplasty, and rotator cuff tear debridement or repair. Follow-up was at least 1 year. The patients were divided into two groups based on whether they had an RtS+ outcome as defined above or an RtS- outcome defined as a return to the previous sport at a lower level, a switch to another sport, or an inability to engage in any sport. The Kerlan-Jobe Orthopaedic Clinic (KJOC) and Constant's score were used to evaluate subjective and objective shoulder function.

RESULTS

Mean follow-up was 7.9 years. Of the 135 patients, 120 (90%) returned to sports after surgery including 70 (52%) to the previous sport at the same level (RtS+ outcome). By univariate analysis, the following factors were associated with an RtS+ outcome: male sex, rotator cuff tear documented intra-operatively, absence of a greater tuberosity cyst on pre-operative imaging studies, and cuff tear debridement. Anterior capsulorrhaphy was associated with worse post-operative pain.

DISCUSSION

The RtS+ rate in this study differed from previously reported values, due to differences in the sports practiced by the patients and to considerable variability in the surgical techniques used. The positive association between presence of a rotator cuff tear and an RtS+ outcome is at variance with most of the previously published data. Some of the apparent discrepancies between our results and those from other countries may be ascribable to differences in the most popular sports.

LEVEL OF EVIDENCE

IV.

Age and sex-related upper body performance differences in competitive young tennis players

Objective

The aims of this study were to analyze the shoulder functional profile of young male and female tennis players and to establish the relationship among physical variables and serve speed.

Methods

A total of 128 Spanish tennis players (Under-13 (n = 32/32 males/females) and Under-15 (n = 36/28 males/females), were tested during National training camps. Tests included passive shoulder range of motion (ROM) for both internal (IR) and external rotation (ER) and isometric strength (i.e., IR and ER) of the dominant/non-dominant shoulders, medicine ball throws (MBT), and serve speed. Age and sex pairwise comparisons were carried using the Hedges’ g index (d_g).

Results

Results showed age and sex effects on serve speed and all MBT, with males showing greater changes (1.51≤d_g≤1.98) with age than females (0.92≤d_g≤1.35; p<0.05). U15 males showed higher (p<0.05) absolute shoulder IR and ER strength than U13, with only significant differences between males and females in the U15. Regarding ROM, U15 males showed a decreased IR ROM compared to U13 (d_g = -0.84; p<0.05) and higher significant IR bilateral deficit (d_g = 0.51; p<0.05). The distances obtained in the different MBT were the variables more correlated to serve speed.

Conclusion

The present results suggest that shoulder strength, medicine ball throws and serve speed increased along with age in young elite tennis players of both sexes. However, a decreased range of motion and bilateral deficit for glenohumeral internal rotation is evident in male under-15 tennis players. Muscle strength, power and shoulder range of motion are key factors for serve speed in young tennis players.

Shoulder internal and external rotation strength and prediction of subsequent injury in water-polo players

Water-polo players have greater isokinetic shoulder strength than age-matched controls. Due to the repetitive demands of throwing, however, water-polo players demonstrate an altered strength ratio, with greater internal rotation (IR) strength relative to external rotation (ER). The relationship between shoulder strength and risk of shoulder injury is unknown. In addition, the effect on test position for strength testing on the reliability of handheld dynamometry (HHD) in this population is not known. The aims were to determine the: (a) Inter-rater reliability of HHD testing of IR and ER strength in two positions: neutral and 90°abduction-90°ER (90-90) and (b) relationship between preseason shoulder strength and occurrence of future injury in sub-elite water-polo players. Two assessors measured shoulder IR and ER strength using HHD in 15 water-polo players across two testing days. Athletes were followed over a 6-month period, and injury was assessed and recorded by the team physiotherapist. Measurement of water-polo players' isometric IR and ER strength in the clinical setting had good to excellent inter-rater reliability; however, systematic error was observed in the neutral position but not the 90-90 position. Irrespective of testing position, the neutral and 90-90 test position showed a significant difference (P = 0.01) in absolute preseason IR and ER mean strength between prospectively injured and non-injured players. There was no significant difference in strength ratio or strength normalized for body mass index. These results suggest that preseason strength testing may help identify players at risk of in-season shoulder injury.

Management of Rotator Cuff Injuries in the Elite Athlete

PURPOSE OF REVIEW

Rotator cuff injuries are a common cause of pain and dysfunction for the elite athlete and can result in time loss from participation. This review highlights the current management of these injuries.

RECENT FINDINGS

Conservative management of rotator cuff injuries continues to be the "gold standard" in the elite athlete. This includes a comprehensive rehabilitation program, anti-inflammatories, and corticosteroid injections. Newer treatment techniques such as intramuscular dry needling and the use of biologics such as platelet-rich plasma and stem cells demonstrate early promising results; however, these modalities require further investigation to determine their effectiveness. Rotator cuff injuries can range from contusions and tendinopathy to full-thickness tears. A comprehensive evaluation is needed to determine the extent of injury and appropriate plan of care. Management strategies can range from rehabilitation to operative intervention and are guided by the size of the tear, time of season, sport, performance limitations, and presence of concomitant pathology.