Shoulder rotator muscle normative values in Indian overhead athletes with and without impingement syndrome

Abstract

Background: Few researchers have examined shoulder strength in different overhead athletes with and without impingement symptoms. To compare internal and external rotation isokinetic peak torque, average torque, average power and fatigue index at different speeds in different overhead athletes.
Methods: 80 male athletes from swimming, badminton, handball and cricket were taken in 2 groups, injured(with impingement) and normal(without impingement) (40 in both groups) between the age group 20-30 years {mean normal group (24.9±2.19), injured group (25.63±1.6)}, with participation in university, state and national level sporting competitions were included, 10 from each sport.
Result: We measured concentric peak torque, average torque, average power, fatigue index of internal and external rotators of the shoulder at speeds of 60 and 120 Radians/sec. Swimmers have the highest values for the outcome variables in both injured and normal groups. Significant group differences are present in the normal group indicating training adaptations for the specific sports. Between the injured and normal groups there are significant differences, showing that impingement affects muscular balance. In the injured athletic group, group differences are significant only for external rotator average torque at higher speed (p=0.03).
Conclusions: differences in between the groups appear to be related more to injury prevalence than to absolute strength. Shoulder dysfunction related to strength deficits also may exist in adult male overhead athletes. Intergroup differences in normal subjects are due to the training adaptations of the respective sports. Preventive shoulder strengthening programs focused on external rotators strength at higher speeds may be warranted for all overhead athletes.

Key words:

isokinetic shoulder rotations, impingement, overhead athletes