Still of major use in neurological clinical examinations for assessing dysfunctions of the pyramidal tract
, the Babinski sign has recently been the subject of a debate whether it should continue to be part of a routine examination.
Sheehan, "The uncrossed lateral pyramidal tract
in higher primates," Journal of Anatomy, vol.
The involved pyramidal tracts
(average length 21.03 mm) were longer than those which were not involved (average length 18.84 mm), especially in diffuse thyroid disease (average length 23.22 mm) with a high statistic significance (p<0.01).
Complementary to this fundamental contribution, on 2 July 1903 in a lecture before the French Society of Neurology, Babinski discussed the reflex movement of the other toes 'spreading out like a fan' (according to Dupre) following extension of the big toe in the case of a syndrome affecting the pyramidal tract
. This presentation was illustrated by a fine photograph showing the shadow of the spread-out toes on the opposite leg.
Somnolence, slurred speech, amnestic dysphasia, and impaired fine motor control, but no meningism, focal signs, pyramidal tract
, or sensation impairment, were observed.
Impulses originate in the motor cortex, going directly to the brain stem and the facial nerve nucleus, via the pyramidal tract
. The face is given space in the motor cortex, specially the lower face, hence we can make fine movements in speech (Rinn, 1984).
That is why we recommend maintaining the term Babinski sign as described originally and using Babinski reflex for "the great toe sign."(3) It should also be remembered that "the great toe sign," or the Babinski reflex, does not mean a disturbance of the pyramidal tract
itself, as usually thought, because this reflex could be present in patients with pure peripheral neuropathies, such as the Guillain-Barre syndrome, as well.(4) We want to stress that heretofore we must give the appropriate credit and meaning to original descriptions in the medical sciences field to avoid more misunderstandings in this new century of evidence-based medicine.
Our previous experimental and clinical observations indicate that a positive ice-water test represents a release from central inhibition, analogous to the release of the Babinski sign after pyramidal tract
lesions |12, 18, 19~.
(3) In classic PKAN the symptoms usually start to appear before age 6 on average around age 3 with profound dystonia, dysarthria, spasticity and pyramidal tract
signs and pigmentary retinopathy leading to night blindness and visual field constriction.
The most important obstacles against eliciting quantitative information about the lesions involving the descending motor pathways are the variabilities in the latency amplitude, and shape of the motor responses elicited by motor cortex stimulation (predominantly caused by the variable activation level of the target muscle) and the uncertainty about whether, via magnetic stimulation, the whole population of the pyramidal tract
fibers can be activated.
showed that the fractional anisotropy (FA) value in the pyramidal tract
, measured by diffusion-tensor-imaging (DTI) on magnetic resonance was decreased on the side of the chronic subdural hematoma which could be responsible for the development of motor weakness in the patients.