Vertigo due to whiplash injury: a neurotological approach.

A series of examinations were carried out to elucidate the characteristics of vertigo due to whiplash injury. In patients with whiplash injury, there are over-excitation of the cervical and/or the lumbar proprioceptors on one hand, and dysfunction of the central nervous system, such as the hypothalamus, the brain stem and the cerebellum, on the other hand. These two etiological factors induce disequilibrium by a trigger-and-target relationship in which the above proprioceptors act as a trigger and the central nervous system acts as a target. This postulate is applicable to the explanation of aural vertigo following whiplash injury. Autonomic reflexes in patients with whiplash injury can be explained not only as due to over-excitation of the cervical sympathetic nerves, but also to that of the cervical and lumbar proprioceptors. In other words, these reflexes are considered as being the proprio-autonomic reflexes. These reflexes are more evident in patients with cervical pain. Cerebellar symptoms can be manifested by over-excitation of the cervical and lumbar proprioceptors. These symptoms are more evident in patients with lumbar pain. The above differences in the autonomic reflexes and cerebellar symptoms of patients with cervical and/or lumbar pains can be explained on the basis of known fiber connections in the central nervous system. Hypertonicity of the cervical and lumbar erector muscles in patients with whiplash injury can be explained not only as due to over-excitation of gamma fibers, but also to that of sympathetic nerves in these muscles. This hypertonicity affects the central nervous system, causing disequilibrium following whiplash injury.