The shoulder is at high risk for injury during overhead sports, in particular in throwing or hitting activities, such as baseball, tennis, handball, and volleyball. In order to create a scientific basis for the prevention of recurrent injuries in overhead athletes, four steps need to be undertaken: (1) risk factors for injury and re-injury need to be defined; (2) established risk factors may be used as return-to-play criteria, with cut-off values based on normative databases; (3) these variables need to be measured using reliable, valid assessment tools and procedures; and (4) preventative training programs need to be designed and implemented into the training program of the athlete in order to prevent re-injury. In general, three risk factors have been defined that may form the basis for recommendations for the prevention of recurrent injury and return to play after injury: glenohumeral internal-rotation deficit (GIRD); rotator cuff strength, in particular the strength of the external rotators; and scapular dyskinesis, in particular scapular position and strength.

This study aimed to provide an age, gender and sport-based normative database for three functional shoulder tests: Y Balance Test - Upper Quarter (YBT-UQ), Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), and Seated Medicine Ball Throw (SMBT). A second aim was to discuss gender, age and sports differences. Finally, correlation between tests was evaluated. Overhead athletes (106 male, 100 female) between 18 and 50 years old and from three different sports (volleyball, tennis, handball) performed all functional tests. A linear mixed or regression model was applied to determine significant differences in test scores between gender, age and sports. Pearson correlation coefficients were analyzed to determine the relationship between tests. Normative values were established and divided by gender, sports and age. Results showed significant gender and age differences for all tests. For YBT-UQ, also significant side and sports differences were recorded. CKCUEST is moderately correlated with SMBT and YBT-UQ. Weak correlation was found between SMBT and YBT-UQ. In conclusion, this study provides normative data for YBT-UQ, CKCUEST and SMBT, which is clinically relevant for functionally screening overhead athletes and benchmark their performance to others from the same gender, age and sports. A combination of included tests is recommended.

Context: Isokinetic testing is used to determine possible deficits in upper extremity strength in overhead athletes. Given that isokinetic testing is restricted to a laboratory setting, field tests, such as the Seated Medicine Ball Throw (SMBT) and Upper Quarter Y-Balance Test (YBT-UQ), were developed to assess upper body performance. The relationships between these field tests and isokinetic strength have not been examined.Objective: To investigate the relationship between isokinetic strength testing for shoulder external and internal rotation and elbow flexion and extension and SMBT distance and YBT-UQ performance in overhead athletes.Design: Cross-sectional study. Setting: Institutional laboratory. Patients or Other Participants: A total of 29 healthy overhead athletes (14 men, 15 women; age ¼ 21.6 6 2.5 years, height ¼ 177.7 6 9.7 cm, mass ¼ 70.3 6 11.5 kg).Intervention(s): A Biodex dynamometer was used to measure the isokinetic strength of the shoulder and elbow muscles. Upper extremity performance was assessed using the SMBT and YBT-UQ.Main Outcome Measure(s): We used Pearson correlation coefficients and coefficients of determination to analyze the relationship between SMBT and YBT-UQ performance and the isokinetic strength variables.Results: We observed moderate to strong correlations between the SMBT and isokinetic shoulder and elbow strength (r range ¼ 0.595À0.855) but no correlations between the YBT-UQ and isokinetic strength variables. The shared variance between these strength variables and the SMBT ranged from 35.4% to 64.5% for shoulder strength and 58.5% to 73.1% for elbow strength.Conclusions: These findings suggested that the SMBT is a reliable, low-cost, and easy-and quick-to-administer alternative to isokinetic testing for evaluating upper extremity strength in a clinical setting. Performance on the YBT-UQ did not seem to be related to upper limb strength and, therefore, cannot be used for this purpose. Using the YBT-UQ for other purposes may have value.Key Words: shoulder, elbow, Seated Medicine Ball Throw, Y-Balance Test Key PointsPerformance on the Seated Medicine Ball Throw was moderately to strongly correlated with isokinetic tests for shoulder external-and internal-rotation muscles and elbow flexors and extensors in a sample of overhead athletes. These observations may provide athletic trainers and physical therapists with a reliable, low-cost, and easy-and quick-to-administer alternative to isokinetic testing for evaluating upper extremity strength in a clinical setting. Performance on the Y-Balance Test-Upper Quarter did not seem to be related to upper limb strength and, therefore, cannot be used for this purpose. Performance on the Y-Balance Test-Upper Quarter can help determine rehabilitation goals for injured overhead athletes because no differences existed between the dominant and nondominant limbs in the study population. Investigators should explore the value of these field tests for preventing shoulder injuries.

During resistance training protocols, people are often encouraged to target the scapular stabilizing musculature (middle and lower trapezius and serratus anterior) while minimizing shoulder prime mover activation (upper trapezius and large glenohumeral muscles) in their training regime, especially in overhead athletes with scapular dyskinesis. To increase the activation levels in the stabilizing muscles without drastically increasing the activation in the prime movers, unstable surfaces are frequently used during closed kinetic chain (CKC) exercises. However, the specific influence of Redcord slings (RS) as an unstable surface tool on the shoulder muscle activation levels has rarely been investigated, despite these results may be used for adequate exercise selection. Therefore, a controlled laboratory study was performed on 47 healthy subjects (age, 22 ± 4.31 years; height, 176 ± 0.083 cm; weight, 69 ± 8.57 kg) during 4 CKC exercises without and with RS: half push-up (HPU), knee push-up (KPU), knee prone bridging plus (KPBP), and pull-up. When using RS, serratus anterior muscle activation decreased during the KPU and KPBP exercise. In addition, a drastic increase in pectoralis major muscle activation was found during the HPU and KPBP exercise. Consequently, the use of RS does not necessarily imply that higher levels of scapular stabilizer muscle activation will be attained. These findings suggest that RS might be an appropriate training tool when used within a general strengthening program but should not be preferred over a stable base of support when training for specific scapular stabilization purposes.

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