Asymmetric vestibular function in the elderly might be a significant contributor to hip fractures

The aim of this study was to assess postural control, vestibular symmetry and health status in otherwise healthy hip fracture subjects and compare these factors with controls. The fracture subjects were recruited from 113 consecutive patients operated 12-33 months earlier. Nineteen of those were otherwise healthy and fulfilled the inclusion criteria. They were assessed and compared with 28 age- and sex-matched controls. Nystagmus after head shake was checked for by video-nystagmoscopy (charged couple device cameras). Vibration sensation was tested with a tuning fork, medical history and posturography of vibration-induced sway were studied. The subjects had a significantly higher frequency of head shake nystagmus (p = 0.03), indicating a vestibular asymmetry and a history of previous fractures (p = 0.002). Nine out of 12 subjects had fallen and sustained the hip fracture towards the slow phase of the nystagmus, which is expected in a vestibular related fall. Losing balance during testing was more frequent among the subjects than among the controls (p = 0.002). The subjects with head shake nystagmus swayed more than those without, especially in the sagittal plane during neck vibration with eyes closed (p < 0.001). Vibration perception was significantly poorer in the operated legs than in the healthy legs (p = 0.021) and in the legs of the controls (p = 0.001). The findings suggest that vestibular asymmetries may contribute to falls and fractures in elderly people. As such asymmetries can be compensated to a certain degree by specific training programs, these might be advisable for elderly people, especially those with a history of falls or fractures or where a vestibular asymmetry is suspected.