Sensomotor function during wearing of lumber corsets.

Aim: Flexible lumbar corsets should contribute to an improved active and pa ssive stabilisation of the lumbar spine. In the present study, the effects of flexible corsets on sensory-motor abilities have been investigated. Meth ods: 24 healthy subjects (m = 10, f = 14, 26.7 years) performed angle- and force-reproduction tasks with and without wearing a flexible corset. The su bjects tried to reproduce trunk flexion angles of 20 degrees und 40 degrees as well as forces of 33% and 66% of the maximum strength of the back exten sor muscles. Additionally, muscular reactions were measured during destabil izing stimuli. Results: No significant differences were found for the repro duction tasks. When wearing the corset, the left erector spinae muscles sho wed a delayed onset (+ 15 ms, p < 0.05), and the obliquus abdominis reached maximal activity more rapidly (- 18 ms, p < 0.05). In the preinnervation p hase the obliquus abdominis (-33%, p < 0.01), in the eccentric phase the er ector spinae (-27%, p < 0.05) and the right obliquus abdominis (-46%, p < 0 .05) and in the concentric phase the right obliquus abdominis (-35%, p < 0. 01) and the rectus abdominis (-32%, p < 0.05) showed tower activities. Conc lusion: The reduced muscle activities with destabilizing stimuli can be int erpreted as the result of an improved passive stabilisation of the lumbar r egion by wearing a flexible corset.