The Babinski sign in the first Italian reports

Camillo Negro (1861-1927) and his method for eliciting the extensor toe sign

The "toe phenomenon", or extensor toe sign, is characterized by the extension (dorsiflexion) of the great toe elicited by plantar stimulation, and indicates pyramidal tract dysfunction. This phenomenon was first extensively described and studied by Joseph Jules François Félix Babiński (1857-1932), who introduced it in clinical practice. In 1912, the famous Italian neurologist Camillo Negro (1861-1927) proposed a new method of eliciting the extensor toe sign by inviting the patient, lying in bed in dorsal decubitus position, to raise the paretic limb with the leg extended on the thigh. This sign appeared during voluntary effort and could not be elicited by raising the unaffected lower limb. Negro was also the first to investigate the influence of cold upon the appearance of the "toe phenomenon" and to propose the use of (faradic) electrical stimulation to evoke it.

Would Francisco Soca have been the first to relate toe phenomenon as pyramidal disorders?

INTRODUCTION

The Uruguayan physician Francisco Soca, who specialized in neurology in Jean-Martin Charcot's clinic, defended a thesis at the Paris Faculty of Medicine in 1888 on Friedreich's ataxia in eleven patients. In this work he described the presence of toe phenomenon.

OBJECTIVE

This historical note presents a toe sign described by the Soca eight years before Babiński's classic description.

DISCUSSION

In the late 1800s Soca completed a specialization in neurology at the service run by Charcot in Paris. He defended an important thesis in 1888 assessing data from 11 Friedreich's ataxia. In his thesis, Soca also described the toe phenomenon and the presence of structural changes in the feet of these patients that were not described in the Friedreich study published in 1863.

CONCLUSION

The Soca's thesis contained the description of toe extension associated with pyramidal tract lesions, eight years later described and further immortalized as Babiński's sign. Therefore, Soca had already publicized this sign as being representative of a pyramidal dysfunction before Babiński or any other neurologist.

Adolph Seeligmüller (1837-1912) and the first graphic illustration of the "toe phenomenon" (later called "Babiński sign") in the medical literature

The "toe phenomenon" refers to the extension (dorsiflexion) of the great toe, which occurs instead of the normal flexion following stimulation of the foot sole. Its clinical significance was not fully appreciated until Joseph Jules François Félix Babiński (1857-1932) described it in 1896. In 1881, Ernst Strümpell (1853-1925) had described a continuous (tonic) extension of the big toe, a finding that years later the French neurologist Jean-Athanase Sicard (1872-1929) recognized as an equivalent of the "toe phenomenon", also indicating pyramidal tract dysfunction. Previously, this phenomenon had been mentioned in patients only passingly and without providing a picture of it. In 1887, the German neurologist Adolph Seeligmüller (1837-1912) mentioned the tonic extension of the big toe among the characteristic clinical features of spastic infantile hemiplegia-a condition first described by the Austrian physician Moritz Benedikt (1835-1920) in 1868. Seeligmüller incorrectly attributed the tonic extension of the big toe to spastic contracture of the extensor hallucis longus muscle. However, he put great emphasis on this sign and considered it worth being illustrated. Adolph Seeligmüller therefore provided the very first graphic illustration of the (tonic) "toe phenomenon" in the medical literature. Of note, the first photographic illustration of this sign made by Babiński appeared only in 1900, when it had already been adopted by neurologists all over the world.