干扰本体感觉和视觉对正常人及单侧前庭功能低下患者的静态姿势的影响

The influence of interrupting visual and somatosensory cues to the static posture of normal subjects and the patients with unilateral vestibular hypofunction

目的观察干扰视觉或本体感觉对正常人和单侧前庭功能低下(unilateral vestibular hypofunction,UVH)患者的静态姿势描记的影响,并探讨正常人和UVH患者维持静态姿势平衡时的策略有无区别。方法60例健康志愿者和28例UVH患者进行如下静态姿势描记试验:(1)睁眼站立于坚硬平板上的直立试验(T1);(2)闭眼站立于坚硬平板直立试验(T2);(3)睁眼站立于海绵上直立试验(T3)。每种条件下各站立30s,分别记录足底压力中心的平均晃动速度(Swayvelocity,SV)作为姿势稳定性的参数。结果(1)正常组和UVH患者组当视觉或本体觉受到干扰时,SV较正常站立时均增加,差异具有非常显著性意义(P值均<0.01);(2)正常组在本体觉受到干扰时的SV比在视觉受到干扰时的SV大,差异具有非常显著性意义(P<0.001);UVH患者组的视觉受到干扰和本体觉受到干扰时,SV比较差异无显著性意义(P=0.051);(3)睁眼站立于坚硬平板时,正常组和UVH患者组的SV比较,差异无显著性意义(P=0.257);本体觉受到干扰时,两组的SV比较,差异也无显著性意义(P=0.232);视觉受到干扰时,UVH患者组比正常组的SV大,且差异有显著性意义(P<0.05)。结论干扰视觉或本体觉对正常人和UVH患者的静态姿势稳定性的影响大小并不完全一致,正常人更依赖本体觉,而UVH患者则更依赖视觉,这可能提示正常人和UVH患者维持静态姿势平衡的策略有所差异。

Objective To investigate the static posturography （SPG） of normal individuals and the patients with unilateral vestibular hypofunction（UVH） when the visual or somatosensory input was interrupted, and discuss the different strategies of normal individuals and the patients with UVH in the regulation of balance. Methods Sixty normal subjects and 28 patients with UVH were assessed using computerized posturography under the different upright stance conditions： （1） standing on the firm surface with eyes open, （2） standing on the firm surface with eyes closed and （3） standing on the foam surface with eyes open for 30 seconds and the sway velocity （SV） was recorded respectively. Closing eyes was used to interrupt the visual input and standing on the foam surface to interrupt the somatosensory input in postural stability. Results （1） For both the normal and UVH groups, the SV increased with either the visual or somatosensory input interrupted（P 〈 0.01）. （2）The SV in the normal group was higher when the somatoseneory input was interrupted compared with that when the visual cue was interrupted（P 〈 0.001）; but the SV in the UVH group had no difference between the two conditions of deprived sensory input（P = 0.051）. （3） The SV in the normal and UVH groups had no difference when they stood on the firm surface with eyes open（P = 0.257）, and also when the somatosensory cue was interrupted（P = 0.232）. When the visual cue was interrupted, however, the SV in the UVH group was higher than that in the normal group （P 〈 0.05）. Conclusion The static balance function of the normal individuals and the UVH patients decreased when the visual or somatosensory cue was interrupted, but the influences differed in degrees： the normal group was apt to depend on the somatosensory cue, while the UVH patients depended on the visual input much more. This may indicate that the normal ones and the UVH patients use the different strategies to keep balance.