Shoulder Adaptations In Elite Female Handball Players

Changes related to shoulder adaptations can affect overhead athletes, including handball players, as handball is a throwing sport that places significant demands on the shoulder. PURPOSE: This study aimed to identify sport-specific adaptations in the shoulder joint, such as changes in the posterior capsule thickness(PCT), supraspinatus tendon thickness(SSTT), and acromio-humeral distance (AHD) in elite female handball players. METHOD: Twenty-eight national handball players (age: 24.8 ± 3.5 years; weight: 67.3 ± 8.4 kg; height: 173.3 ± 6.27 cm, 16.89 ± 2.67 hours handball training per week) participated in the study. A complete shoulder examination was performed, and all rotational angles were measured to assess for glenohumeral internal rotation deficit (GIRD). The peak torque of internal and external rotators was assessed during concentric action at 60°/s and 180°/s. For the ultrasound examination, measurements were obtained using a 4-15 MHz linear probe. SSTT was measured in the transverse plane at 5, 10, and 15 mm lateral to the landmark of the biceps tendon in the crass position. For other measurements, athletes sat upright with their forearms on their thighs in the neutral position. AHD was measured as the shortest distance between the inferolateral border of the anterior acromion and the humeral head. The posterior capsule, located between the humeral head and rotator cuff, was identified and the thickness was measured 5 mm from the glenoid labrum to the humeral side. RESULTS: - Parameter Dominant Shoulder (Mean ± SD) Non-Dominant Shoulder (Mean ± SD) p-value SSP Thickness 5.54 ± 0.96 mm 5.0 ± 1.0 mm 0.048* PCT 1.04 ± 0.30 mm 0.88 ± 0.28 mm 0.055† AHD 11.32 ± 1.81 mm 11.20 ± 1.97 mm 0.806 IR Rotational Range of Motion 41.36 ± 14.68° 54.60 ± 11.99° <0.001** ER Rotational Range of Motion 99.54 ± 17.24° 91.79 ± 11.56° 0.013* IR Peak Torque (60°) 40.6 ± 7.75 NM 37.9 ± 8.71 NM 0.245 IR Peak Torque (180°) 36.88 ± 7.59 NM 33.46 ± 6.88 NM 0.095 ER Peak Torque (60°) 24.24 ± 5.59 NM 23.16 ± 5.99 NM 0.504 ER Peak Torque (180°) 21.79 ± 6.4 NM 20.37 ± 5.87 NM 0.409 Table 1* indicates statistical significance at p < 0.05 ** indicates statistical significance at p < 0.001 † indicates marginal significance The percentage difference in thickness between the posterior capsules of the dominant and non-dominant sides was significantly different between individuals with and without GIRD (p = .014), indicating that GIRD is correlated with increased thickness. CONCLUSION: Results showed asymmetries between throwing and non-throwing shoulders, with differences in glenohumeral rotation and SSTT favoring the throwing shoulder. The posterior capsule was also thicker in the throwing shoulder.