IS THE KICK SERVE LINKED WITH PARS ABNORMALITIES IN ELITE ADOLESCENT TENNIS PLAYERS?

The purpose of this study was to compare lumbar kinetics in elite adolescent tennis players with and without pars abnormalities. A 3D motion capture system was used to capture lumbar spine kinetics while 24 right-handed elite adolescent tennis players (male = 14, female = 10, 9 players with pars abnormalities) performed kick serves. Players without pathology were found to have significantly greater peak lumbar posterior force (7.3 N/kg greater), left lateral flexion force (4 N/kg greater), right lateral flexion force (3.4 N/kg greater), flexion moment (2 Nm/kg greater) and left rotation moment (1.2 Nm/kg greater) during the drive phase. Interestingly, no differences were observed for peak kinetic values during the forward-swing phase. Those with pars abnormalities had lower lumbar loading overall compared with those without pars abnormalities