Value of self-induced plantar reflex in distinguishing Babinski from withdrawal
Citation Manager Formats
Make Comment
See Comments

Interpretation of the plantar response can be difficult, resulting in inter- and intraobserver discordance. A common source of confusion is that tickle-induced withdrawal can cause dorsiflexion of the great toe in a pattern similar to the Babinski sign.
Ticklish sensation, present when the stimulus is introduced by a person other than the subject, is reduced by self-stimulation. The cause of this inhibition has been shown to be in the cerebellum.1
We reasoned that self-induction of the plantar response should reduce withdrawal, obviating the potential confusion with a Babinski sign. The patient would sit down, grab the foot, and scratch the sole with a sharp object in a posture similar to the famous Greco-Roman Spinario sculpture of a boy withdrawing a thorn from the sole of his foot, studied and drafted by Peter Paul Rubens (1577–1640) (figure).
Sir Peter Paul Rubens' 1601 study of the famous Greco-Roman sculpture, showing a person removing a thorn from the sole of his foot. © The Trustees of British Museum; reproduced with permission.
In the process of reviewing the available literature, we were surprised to discover that C. Miller Fisher2 had reported this observation 4 decades ago.
See the video on the Neurology® Web site at Neurology.org.
Footnotes
Supplemental data at Neurology.org
Author contributions: Dr. Sohrab: study concept and design, acquisition of data, analysis and interpretation. Dr. Gelb: study concept and design, acquisition of data, analysis and interpretation.
Study funding: No targeted funding reported.
Disclosure: Dr. Sohrab reports no disclosures. Dr. Gelb has received royalties from Oxford University Press and honoraria from the AAN (for Continuum®), from UpToDate, and from MedLink (all for chapters he wrote). Go to Neurology.org for full disclosures.
- © 2016 American Academy of Neurology
Letters: Rapid online correspondence
REQUIREMENTS
You must ensure that your Disclosures have been updated within the previous six months. Please go to our Submission Site to add or update your Disclosure information.
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.
You May Also be Interested in
Hastening the Diagnosis of Amyotrophic Lateral Sclerosis
Dr. Brian Callaghan and Dr. Kellen Quigg
► Watch
Topics Discussed
Alert Me
Recommended articles
-
Articles
Should the Babinski sign be part of the routine neurologic examination?Timothy M. Miller, S. Claiborne Johnston et al.Neurology, October 24, 2005 -
ARTICLES
Multiple cerebral lesions complicating therapy with interleukin-2B. Illowsk Karp, J. C. Yang, M. Khorsand et al.Neurology, August 01, 1996 -
Articles
The D178N (cis-129M) "fatal familial insomnia" mutation associated with diverse clinicopathologic phenotypes in an Australian kindredC. A. McLean, E. Storey, R.J.M. Gardner et al.Neurology, August 01, 1997 -
Clinical and Ethical Challenges
The plantar reflexA study of observer agreement, sensitivity, and observer biasRui Araújo, João Firmino-Machado, Pedro Correia et al.Neurology: Clinical Practice, August 06, 2015