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Purpose: Repetitive and asymmetric movements in tennis can result in biomechanical adaptation in shoulder joint. The aim of this study was to investigate the differences in shoulder range of motion (ROM), strength, and functional performance tests between the dominant and nondominant shoulders, as well as to identify gender differences in junior tennis players., Methods: Forty-two junior tennis players (age mean: 11.3 [1.2] y, body mass index 18.3 [2.4] kg/m2) were included in the study. Shoulder internal rotation (IR), external rotation (ER) ROM, and total ROM, IR and ER isokinetic strength and closed kinetic chain upper-extremity stability, seated medicine ball throw used, grip hold tests were applied bilaterally. Paired sample t test and Student t test were used to compare the differences., Results: ER ROM was greater, while IR ROM and total ROM were lower on the dominant shoulder (all P values < .05). Nineteen players had glenohumeral IR deficit (IR ROM difference >13°). The players had a greater ER strength on the dominant side and similar IR strength between shoulders. There was significant difference in seated medicine ball throw results between the dominant and nondominant sides (P < .001). The mean distance for bilateral seated medicine ball throw was 377.02 (85.70) m, and closed kinetic chain upper-extremity stability results were calculated as a mean of 15.85 (1.72) touches. Differences between the genders: total ROM of the dominant shoulder was higher in female players (P = .045), the IR PT/BW at 60°/s angular speed was higher in male players' dominant shoulder (P = .030), and closed kinetic chain upper-extremity stability performance was higher in male players (P = .019)., Conclusions: Adolescent tennis players demonstrated differences in strength, ROM, and functional performance results between the dominant and nondominant shoulders. Gender differences were also seen in the aforementioned parameters in junior tennis players. Determining these differences may improve our understanding of sport-specific shoulder joint adaptations in tennis.

Context: Sport-specific adaptations at the glenohumeral joint could occur in adolescent athletes because they start participating in high-performance sports in early childhood., Objective: To investigate shoulder-rotator strength, internal-rotation (IR) and external-rotation (ER) range of motion (ROM), and acromiohumeral distance (AHD) in asymptomatic adolescent volleyball attackers to determine if they have risk factors for injury., Design: Cross-sectional study., Setting: University laboratory., Participants: Thirty-nine adolescent high school-aged volleyball attackers (22 boys, 17 girls; age = 16.0 ± 1.4 years, height = 179.2 ± 9.0 cm, mass = 67.1 ± 10.9 kg, body mass index = 20.7 ± 2.6 kg/m 2 )., Main Outcome Measure(s): Shoulder IR and ER ROM, total-rotation ROM, glenohumeral IR deficit, AHD, and concentric and eccentric strength of the shoulder internal and external rotators were tested bilaterally., Results: External-rotation ROM was greater (t 38 = 4.92, P < .001), but IR ROM (t 38 = -8.61, P < .001) and total ROM (t 38 = -3.55, P = .01) were less in the dominant shoulder, and 15 athletes had a glenohumeral IR deficit (IR ROM loss > 18°). We observed greater concentric internal-rotator (t 38 = 2.89, P = .006) and eccentric external-rotator (t 38 = 2.65, P = .01) strength in the dominant than in the nondominant shoulder. The AHD was less in the dominant shoulder (t 38 = -3.60, P < .001)., Conclusions: Adolescent volleyball attackers demonstrated decreased IR ROM, total ROM, and AHD and increased ER ROM in their dominant shoulder. Therefore, routine screening of adolescent athletes and designing training programs for hazardous adaptive changes could be important in preventing shoulder injuries.

Context: Glenohumeral (GH) internal-rotation deficit (GIRD) and lower eccentric external-rotator (ER) to concentric internal-rotator (IR) strength (ER:IR) ratio have been documented as risk factors for shoulder injuries, but there is no information on whether GIRD has an adverse effect on ER:IR ratio in adolescent overhead athletes., Objectives: The aim of this study was to investigate the effects of GIRD on functional ER:IR ratio of the adolescent overhead athletes., Design: Cross-sectional study., Setting: University research laboratory., Participants: 52 adolescent overhead athletes., Main Outcome Measures: To determine GIRD, the range of GH IR and ER motion was measured with a digital inclinometer. An isokinetic dynamometer was used to assess eccentric and concentric IR and ER muscle strength of the dominant and nondominant shoulders. One-way ANCOVA where sport type was set as a covariate was used to analyze the difference between athletes with and without GIRD., Results: After standardized examinations of all shoulders, the athletes were divided into 2 groups, shoulders with (n = 27) and without GIRD (n = 25). There was a significant difference between groups in functional ER:IR ratio (P < .001). Athletes with GIRD had lower ER:IR ratio (0.56) than athletes without GIRD (0.83)., Conclusions: As GIRD has an adverse effect on functional ratio of the shoulder-rotator muscles, interventions for adolescent overhead athletes should include improving GH-rotation range of motion.

Study Design: Controlled laboratory study using within-group comparisons. Objectives To compare scapular kinematics between active and resisted shoulder elevation performed in the sagittal (flexion), frontal (abduction), and scapular (scapular abduction) planes., Background: Several studies have documented scapular kinematics during arm elevation against an external load; however, there is little information on how scapular kinematics change with loading provided by elastic bands, an exercise approach often used in the clinic., Methods: Thirty-two men without shoulder pathology participated in the study. The level of resistance to be used for each individual was determined prior to data collection and standardized by perceived effort on a Borg scale. Three-dimensional scapular kinematics were recorded with an electromagnetic tracking device in all 3 planes of shoulder elevation for both the unloaded (active) and loaded (resisted) conditions. Data for scapular kinematics were analyzed at 30°, 60°, 90°, and 120° of humerothoracic elevation and lowering. Comparisons between loading conditions were made using analysis-of-variance models., Results: In general, for all 3 planes of movement, the scapula was more downwardly rotated and anteriorly tilted during the elevation phase and more so during the lowering phase of shoulder elevation when performed against elastic resistance. While some of the statistically significant differences might not have been large enough to be considered clinically meaningful, some values were of a magnitude similar to previously reported differences between healthy and symptomatic individuals., Conclusions: The changes in scapular motion during the loaded condition were relatively small in this population with normal scapular motion, but they were in a direction that would be considered to have potential to lead to injuries, suggesting caution when using these exercises in individuals with poor scapular control.

Objective: To investigate the effect of a 12-wk weighted-jump-rope training program on shoulder strength., Design: Pretest to posttest experimental design., Setting: University sports physiotherapy laboratory., Participants: 24 healthy volleyball players age 13-16 y., Intervention: Group 1 took weighted-rope training (n = 9), group 2 took unweighted-rope training (n = 8), and group 3 did not train with any specific program (n = 7)., Main Outcome Measures: Players' strength determined with an isokinetic dynamometer (Isomed 2000) at 180 and 60 degrees on external and internal rotators, supraspinatus peak torque, and total work of the dominant shoulder. Kruskal-Wallis and Mann-Whitney U tests were used to determine the difference among the groups., Results: At pretraining evaluation, there were no significant differences in the test scores of the isokinetic test of full can and empty can between the groups at 60 and 180 degrees. There was no statistically significant difference for 60 and 180 degrees between pretraining and posttraining assessment (P > .05) except that total eccentric work increased in groups 1 and 3 but decreased in group 2 at 180 degrees during the full can (P < .05). There was no significant difference among the groups between the pretraining and posttraining testing at both 180 and 60 degrees for the empty can (P > .05). Internal-rotation values at 60 and 180 degrees decreased for both peak torque and total work for all groups. External-rotation peak torque and total work at 60 degrees increased for group 1. External-rotation peak torque and total work at 180 degrees increased for all groups., Conclusions: The results indicate that a jump-rope training program is a good conditioning method for overhead athletes because of its potential benefits to shoulder strength.

Objective: The aim of this study was to evaluate the initial effects of scapular mobilization (SM) on shoulder range of motion (ROM), scapular upward rotation, pain, and function., Design: Pretest-posttest for 3 groups (SM, sham, and control)., Setting: A double-blinded, randomized, placebo-controlled trial was conducted to evaluate the initial effect of the SM at a sports physiotherapy clinic., Participants: 39 subjects (22 women, 17 men; mean age 54.30 +/- 14.16 y, age range 20-77 y)., Interventions: A visual analog scale, ROM, scapular upward rotation, and function were assessed before and just after SM. SM (n = 13) consisted of the application of superoinferior gliding, rotations, and distraction to the scapula. The sham (n = 13) condition replicated the treatment condition except for the hand positioning. The control group (n = 13) did not undergo any physiotherapy and rehabilitation program., Main Outcome Measures: Pain severity was assessed with a visual analog scale. Scapular upward rotation was measured with a baseline digital inclinometer. Constant Shoulder Score (CSS) was used to measure shoulder function., Results: After SM, we found significant improvements for shoulder ROM, scapular upward rotation, and CSS between pretreatment and posttreatment compared with the sham and control groups. In the sham group, shoulder-ROM values increased or decreased for the shoulder and scapular upward rotation was not changed. Pain, ROM, and physical function of the shoulder were not significantly different in the sham group than in controls (P > .05)., Conclusions: SM may be a useful manual therapy technique to apply to participants with a painful limitation of the shoulder. SM increases ROM and decreases pain intensity.

The purpose of this study was to measure isokinetically glenohumeral joint movement peak torque and work in professional basketball, volleyball, handball and baseball players and determine whether significant differences exist between the dominant and non-dominant extremity in athletes and controls. Eighty healthy professional overhead athletes (basketball, volleyball, handball and baseball players) and 20 controls were tested bilaterally on a CYBEX 6000 isokinetic dynamometer at 60 degrees and 180 degrees s(-1) for diagonal pattern of the glenohumeral joint. A standardized protocol and testing guidelines were strictly followed. The range of motion of internal rotation (IR) on the dominant side of baseball players was significantly smaller than those on the dominant side of basketball, handball and volleyball players, and controls (P<0.01). Flexion/abduction/external rotation were consistently higher on the dominant arm (8.5%) for peak torque at 60 degrees s(-1) in baseball players, and bilateral ratios were lower on the dominant arm (14.8%) for peak torque at 180 degrees s(-1) in basketball players. The results of this study are important for the application and interpretation of isokinetic data and flexibility and mobility characteristics on unilaterally dominant overhead athletes. Functional weakness in external rotators, mobility impairments in IR and muscle imbalance have been shown in the dominant arm of these overhead athletes.

Background: To determine range of motion and capsular characteristics of dominant and nondominant shoulders in baseball players. Our hypothesis was that there is a significant difference between dominant and nondominant range of motion in collegiate baseball players with unoperated and without shoulder pain., Design: prospective, range of motion measurements during regular season., Setting: two collegiate baseball teams in Houston., Participants: 15 pitchers and 23 position players., Main Outcome Measures: shoulder range of motion was evaluated by goniometric technique in all baseball players. Horizontal adduction (cross body reach test) and active internal rotation (reach behind back) in standing position and external rotation and internal rotation in supine lying position were measured for each player., Results: Average external rotation with the arm in 90 degrees of abduction was significantly greater and average internal rotation was less in the dominant shoulder than in the nondominant shoulders, both in pitchers and position players. There was no statistical difference in shoulder horizontal adduction. Both dominant and nondominant shoulders of pitchers had greater average range of motion in horizontal adduction and external rotation at 90 degrees of abduction and less average internal rotation than those of position players. Although there was a significant difference in active internal rotation as cm between dominant and nondominant shoulders both in both groups, no difference was found between pitchers and position players., Conclusions: Differences in the range of motion in the throwing shoulder of baseball players exist involved in overhead throwing motions and should be considered in rehabilitation of the upper extremity after injury and in the prevention of injury for pitchers and position players.