Trunk rotational strength in adolescent athletes with/without back pain.

Aim: the purpose was to examine trunk rotational strength in adolescent athletes with (BP) and without (H) back pain. Methods: a pain assessment (VAS: visual analog scale) was used in 47 adolescent athletes to categorize subjects to BP (VAS>0.5) and H (VAS<0.5). According to back pain level n=12 athletes with back pain (BP: m/f: n = 3/9; 15±2yrs; 1.73±0.08m; 63±9kg; training: 17±6h/week) and n=34 healthy subjects (H: m/f: n=19/15; 15±2yrs; 1.69±0.11m; 61±15kg; training: 16±6h/week) could be identified. Peak torque of trunk rotation (left/right) was tested on an isokinetic dynamometer (Con-trex WS) in isometric (PTiso), concentric (30°/s; PTcon) and eccentric (30°/s; PTecc) mode. Peak torque [Nm] for right and left side and differences between sides (left-right) were calculated with mean±SD. Group differences were analysed by student's t-test (α=0.05). Results: in BP absolute peak torques were PTiso 60.5±26.3Nm, PTcon 66.2±25.0Nm and PTecc 74.4±19.4Nm, in H PTiso 55.5±17.1Nm, PTcon 65.7±18.9Nm and PTecc 69.5±18.5Nm. Mean side differences for BP were 9.4±7.2/15.8±11.7/8.1±7.4Nm (PTiso/PTcon/PTecc) and for H 8.7±7.6/8.9±9.1/7.2±6.5Nm (PTiso/PTcon/PTecc). No group differences were observed for trunk rotational strength measures. There were no group differences for side comparison (p>0.05) except in PTcon (p=0.04). Discussion: in adolescent athletes trunk rotational strength does not differentiate between low back pain. This contradicts data showing reduced trunk strength in adult non athletes. Regardless of back pain the high amount of training in athletes could serve as an explanation model. Conclusion: interpretation of maximum trunk strength capacity has to be seen critical in low back pain athletes. [ABSTRACT FROM AUTHOR]