Postural sway changes in genu recurvatum deformity during standing with manipulation of visual and proprioceptive systems

Abstract

ObjectivesGenu recurvatum deformity shifts the mechanical axis of lower extremity posteriorly which may disturb the balance and lead to injury. The aim of this research was to compare postural sways in genu recurvatum subjects with healthy controls while manipulating visual and proprioceptive systems. Methods10 female subjects with genu recurvatum (20.04 ± 4.64 years) and 11 female healthy controls (20.11 ± 4.64 years) participated in the study. The back knee angle was measured using a goniometer. Dynamic BIODEX balance system was used to measure the total, anteroposterior, and mediolateral postural sways while manipulating the stability of the base of support (stable versus unstable) and visual system (open versus closed eyes). ResultDuring standing on the stable level, in both visual conditions, genu recurvatum subjects demonstrated greater total and anteroposterior postural sways than controls in both standing on the right and left foot (p<0.05). Similarly, when standing on the unstable base of support, in all conditions, the postural sways of genu recurvatum subjects were significantly greater than controls in both right and left foot (p<0.05). The vision had a main effect on postural control of genu recurvatum group (p=0.0001). There was a significant interaction between vision, the stability of the base of support and group factors (p=0.003). ConclusionThe results indicated that genu recurvatum subjects have a proprioceptive deficiency and they mainly rely on visual system inputs to control and maintain their balance. Thus, the proprioceptive system and balance control should be considered in assessment and designing an appropriate treatment regimen for genu recurvatum.