Category · 2
Disequilibrium
Unsteadiness on the feet — a sense of being off-balance when standing or walking — with no illusion that the world is moving. The hallmark complaint is a fear of falling.
Balance as a three-legged stool
Staying upright relies on three senses working together: the eyes, the inner-ear balance organs, and position sensefrom the joints and feet. Disequilibrium happens when one or more of these fails, so the person feels wobbly — especially in the dark or on uneven ground, when vision can't compensate.
It is most common in older people, who often have several of these systems declining at once. Unlike vertigo, there's no spinning — just instability and a fear of falling.
Disequilibrium reflects failed integration of vestibular, proprioceptive, and visual inputs for upright balance.1 Common causes are bilateral vestibular hypofunction, proprioceptive loss (peripheral neuropathy), cerebellar atrophy, and extrapyramidal disease such as Parkinson's.
Bilateral vestibular loss — often from ototoxic drugs like gentamicin — gives profound instability in the dark and an abnormal vestibulo-ocular reflex on the head impulse test or dynamic visual acuity testing.3
Localise by the pattern: midline cerebellar (vermis) disease gives truncal instability and a broad-based gait; basal-ganglia disorders give shuffling, impaired postural reflexes, and freezing; sensory ataxia gives a positive Romberg and worsening in the dark. Management is multifactorial — medication review, sensory optimisation, and tailored vestibular rehabilitation.2
- Unsteady on the feet
Ask“Off-balance when standing or walking, but without any spinning?”
Disequilibrium — multisensory, cerebellar, or extrapyramidal.
Bilateral vestibulopathyCerebellar ataxiaParkinsonism - Worse in the dark
Ask“Much worse in the dark or on uneven ground, drifting to one side?”
Loss of vestibular/proprioceptive cues with visual reliance.
Bilateral vestibulopathyPeripheral neuropathy - Vision bounces when walking
Ask“Does your vision bounce or blur when you walk (oscillopsia)?”
Bilateral vestibular loss — often after ototoxic drugs (gentamicin).
Bilateral vestibulopathy