players with scapular dyskinesia present a smaller subacromial space than non-athletes was investigated. Additionally, the correlation between the size of the subacromial space and abnormalities in scapular movement during arm abduction was studied.control participants were enrolled in the study. Participation was restricted to elite-level, junior tennis players who had no current shoulder pain or history of shoulder injuries.dyskinesia by a single physician and by ultrasound, with the results analysed in a blind fashion by a single radiologist.participants presented with scapular dyskinesia. Of the 106 shoulders evaluated, 39.6% of tennis players and 10% of control participants presented with scapular dyskinesia in the clinical examination (p = 0.005). Ultrasonographic measurements demonstrated that tennis players presented statistically smaller subacromial spaces compared with control participants (p,0.001). A decrease in the subacromial space was observed in tennis players when the shoulder was raised from 0u to 60u of abduction; however, dyskinesia-afflicted athletes demonstrated a significantly greater decrease following this movement (19.3 vs 13.8 mm, p = 0.002).tennis players with scapular dyskinesia present a smaller subacromial space than control participants. Furthermore, when the shoulder was analysed dynamically, moving from neutral abduction to 60u of elevation, the tennis players with scapular dyskinesia presented a greater reduction in the subacromial space compared with unaffected athletes.Shoulder injuries are extremely common among competitive tennis players.

The aim of this study was to compare muscle mechanical properties (using tensiomyography-TMG) and jumping performance of endurance and power athletes and to quantify the associations between TMG parameters and jumping performance indices. Forty-one high-level track and field athletes from power (n = 22; mean ± SD age, height, and weight were 27.2 ± 3.6 years; 180.2 ± 5.4 cm; and 79.4 ± 8.6 kg, respectively) and endurance (endurance runners and triathletes; n = 19; mean ± SD age, height, and weight were 27.1 ± 6.9 years; 169.6 ± 9.8 cm; 62.2 ± 13.1 kg, respectively) specialties had the mechanical properties of their rectus femoris (RF) and biceps femoris (BF) assessed by TMG. Muscle displacement (Dm), contraction time (Tc), and delay time (Td) were retained for analyses. Furthermore, they performed squat jumps (SJs), countermovement jumps (CMJs), and drop jumps to assess reactive strength index (RSI), using a contact platform. Comparisons between groups were performed using differences based on magnitudes, and associations were quantified by the Spearman's ρ correlation. Power athletes showed almost certain higher performance in all jumping performance indices when compared with endurance athletes (SJ = 44.9 ± 4.1 vs. 30.7 ± 6.8 cm; CMJ = 48.9 ± 4.5 vs. 33.6 ± 7.2 cm; RSI = 2.19 ± 0.58 vs. 0.84 ± 0.39, for power and endurance athletes, mean ± SD, respectively; 00/00/100, almost certain, p ≤ 0.05), along with better contractile indices reflected by lower Dm, Tc, and Td (Tc BF = 14.3 ± 2.3 vs. 19.4 ± 3.3 milliseconds; Dm BF = 1.67 ± 1.05 vs. 4.23 ± 1.75 mm; Td BF = 16.8 ± 1.6 vs. 19.6 ± 1.3 milliseconds; Tc RF = 18.3 ± 2.8 vs. 22.9 ± 4.0 milliseconds; Dm RF = 4.98 ± 3.71 vs. 8.88 ± 3.45 mm; Td RF = 17.5 ± 1.0 vs. 20.9 ± 1.6 milliseconds, for power and endurance athletes, mean ± SD, respectively; 00/00/100, almost certain, p ≤ 0.05). Moderate correlations (Spearman's ρ between -0.61 and -0.72) were found between TMG and jumping performance. The power group presented better performance in vertical jumps, supporting the validity of these tests to distinguish between endurance and power athletes. Furthermore, TMG can discriminate the "athlete-type" using noninvasive indices moderately correlated with explosive lower-body performance. In summary, both vertical jump and TMG assessments could be useful in identifying and selecting young athletes.

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Objective: To establish normative data for muscle performance during isokinetic horizontal abduction and adduction of the shoulder in elite junior tennis players. Methods: Thirty six tennis players were evaluated (23 male, 13 female; mean age 14 years (range 12-18)). An isokinetic dynamometer was used to test the shoulder horizontal abductors and adductors at 60 and 180˚/s. Absolute and relative peak torque (PT and PT/BW), total work (TW), endurance ratio (ER), and the ratio of the peak torque between horizontal abductors and adductors (HAB/HAD ratio) were recorded. Data were compared for the dominant and non-dominant shoulders, horizontal abductor and adductor muscles, and between players grouped according to age. Results: The dominant shoulder was significantly (p,0.05) stronger than the non-dominant shoulder in all variables except ER and HAB/HAD ratio. The abductors were significantly (p,0.05) weaker than the adductors in all subjects. The type of backhand (one handed or two handed) did not influence the strength of the shoulder horizontal abductors on the dominant side. The number of years of tennis practice had an effect on muscle strength as evaluated by absolute data (PT and TW) but not relative measurements (PT/ BW and TW/BW). Conclusion: The findings confirm that horizontal abduction and adduction are stronger in the dominant shoulder of junior tennis players. The clinical relevance of these findings is not established, and more studies are needed to compare tennis players with athletes from other sports and non-athletes.

Background: Overuse injuries are a frequent occurrence among competitive athletes. When analysing the incidence of overuse injuries in tennis players, it has been determined that a significant number of these injures occur in the upper limb area. In this study, we describe five cases of a stress-induced injury to the middle and distal humerus occurring mainly due to repetitive serving. Methods: Athletes studied were competitive tennis players and elite junior players, two of whom played at international level. Four of the five were male. In all cases, diagnosis was confirmed by magnetic resonance imaging examination. The treatment of middle and distal humeral stress reactions consisted of physical therapy, which focused on analgesia and muscle strengthening. In addition, we analysed each tennis player's strokes in order to identify modifications that would decrease the amount of stress that the upper limbs were subjected to during the service motion. Results: The players in our study missed on average 3 weeks of play and at follow-up after 1 year were able to play symptom free. Conclusions: Our study highlights the need for coaches, physicians and players to be aware of distal humeral pain and understand treatment options in order to prevent further injury, including stress fractures.