Reflex Amplitudes Increas Ed Post a 10-week S Tabilization Exercis E Program in S Ubjects with Recurrent Low Back Pain

INTRODUCTION Delayed muscle onsets have been observed in patients with LBP in experiments involving sudden loading of the trunk [1,2]. A ltered muscle responses contribute to impaired postural control and instability that may be a contributing factor to the recurrence of LBP [1]. SE programs have been shown to decrease the risk of LBP recurrence in a select group of patients with acute, first episode LBP [3]. It is not known if SE programs influence the trunk muscle response patterns to sudden perturbations. It was hypothesized that patients with LBP would have delayed and dampened trunk extensor muscle reflex responses compared to the CNTL subjects and a 10-week SE program would improve the reflexes in the patients with LBP. A perturbation test was used to study the trunk muscle reflexes in 13 patients with subacute, recurrent LBP, before and after a 10 week trunk SE program and in 13 CNTL subjects.