AGE-SENSITIVE TIME-RELATED TENSILE MODEL OF HUMAN LUMBAR SPINE SEGMENTS IN VIVO

摘要

The goal of this study was to create age-sensitive numerical tensile model of human lumbar-lumbosacral motion segments for numerical simulation of traction therapies. The model is based on a large-scale experimental analysis of elongations of human lumbar segments in pure centric tension, when the effect of muscles can be excluded. Time-dependent in vivo elongations of segments L3-L4, L4-L5 and L5-S1 have been measured during the usual traction hydrotherapy of patients, by using a subaqual ultrasound measuring method documented by Kurutz et al. in [1] and [2]. Elongations of segments were considered as change of the distance between two neighbouring spinous processes. Patients were freely suspended on cervical support in lukewarm water for 20 minutes, with fully relaxed muscles. Patients with less degenerated segments have been loaded by 20-20 N extra weights on ankles, prescribed by medical initiation. For patients with more degenerated segments the extra weight load were contraindicated, thus, they have been suspended without any extra load. Based on the measured elongations of segments L3-L4, L4-L5 and L5-S1 in terms of certain biomechanical parameters, parameter-dependent numerical lumbar-lumbosacral FSU models L3-S1 have been created. In this paper the age-sensitive model is considered only.