Which reflex is stimulated by stroking the sole of the foot with a sharp object
This reflex in human infants can be regarded as a foundation of responses that were once essential for ape infants in arboreal life. The spinal center for this reflex is most probably located at the L5-S2 levels, which are controlled by higher brain structures. Nonprimary motor areas may exert regulatory control of the spinal reflex mechanism through interneurons. In infants, this reflex can be provoked due to insufficient control of the spinal mechanism by the immature brain. In adults, lesions in nonprimary motor areas may cause a release of inhibitory control by spinal interneurons, leading to a reappearance of the reflex.[1] [2] Show
Age incidence-According to research done by Brain and Curran in fifty participants this reflex was evident in all young ones aged equal to or less than 9 months ,while it had disintegrated in all participants over the age of 2 years.[3] In an experimental study done by Gentry and Aldrich all the participants lesser than 6 months showed signs of the reflex and also in the same research during the time of 8-9 months of the age, maximum loss of this reflex was noted.[4] Prevalence-According to Stirnimann (1940), 984 out of 1,000 normal newborns gave response to the tonic plantar grasp reflex. The plantar grasp was more noticeable in newborns when compared to the Babinski sign.[5] In healthy adults aged 65 and older it is approximated to be 0.1% and in adults 65 and older with mild cognitive impairment is estimated to be 1.7%, and in adults 65 and older with dementia it is evaluated to be 18.4%.[6] Infant lying on a flat surface in the supine position while awake, head and arms at the neutral position. [7][8][9][10][1] Care should be taken to keep the subject’s head facing the midline, to avoid the influence of the asymmetric tonic neck reflex.[1] The plantar grasp reflex is elicited:-
Normal Response[edit | edit source]In Infants-The lateral surfaces of the foot bend as if to make a cup out of the plantar surface.[11] It consists of the flexion and adduction of all toes as if the toes were firmly grasping the stimulating object[3]; there is hollowing of the sole with some wrinkling of the skin. If the toes also flex, this is called the tonic foot response.[11] It is tonic in character, because the posture is often maintained for 15 or 30 seconds, or longer during early infancy[3] In adults- no response - as it diminishes in later life. Abnormal Response[edit | edit source]In Infants- No response means there is underlying pathology. In adults- If flexion or adduction of toes occurs it means there is underlying pathology. The plantar grasp reflex can be elicited in all normal infants from 25 weeks of postconceptional age until the end of 6 months of corrected age according to the expected birth date.[1] All health care professionals are aware of this term “Babinski Sign”. It is an essential part of any Neuro-Assessment. As any other procedure, this sign is also topic of debate for a long time. However its use in clinical routine remains unabated. It was on February 22, 1896, that Joseph Francois Felix Babinski published his first report on ‘reflexe cutane plantaire’ [cutaneous plantar reflex] which became the sign that bears his name: ‘the Babinski sign’.[1] He referred to the sign as “phénomène des orteils” (toes phenomenon) but is now usually referred to eponymously as the “Babinski sign” or descriptively as the extensor plantar response. This eponym refers to the dorsiflexion of the great toe with or without fanning of the other toes and withdrawal of the leg, on plantar stimulation in patients with pyramidal tract dysfunction. The neurophysiology of this reflex has not been completely elucidated.
Non- Neurological Causes of Extensor Plantar Response[1][edit | edit source]
Place the patient in a supine position and tell him or her that you are going to scratch the foot. Fixate the foot by grasping the ankle or medial surface with the examiner's hand that will be closest to the midline of the patient: examiner's left hand when the patient's left foot is being tested, and vice versa with the right foot. The first line to be stroked begins a few centimeters distal to the heel and is situated at the junction of the dorsal and plantar surfaces of the foot. The line extends to a point just behind the toes and then turns medially across the transverse arch of the foot. Stroke slowly, taking 5 or 6 seconds to complete the motion. Do not dig into the sole, but stroke.
The normal and pathological responses to plantar stimulation are succinctly described by Babinski in his original communication [4] These rules have been shown to improve accuracy of the sign when compared against clinical and electromyographic recordings[5]
Potential causes of an incorrectly interpreted positive Babinski sign[6][edit | edit source]
An extensor response may be present when there is no damage to the pyramidal tract. The Babinski test along with tests introduced by Chaddock, Gordon, and Oppenheim respectively all test the integrity of the CST. Which reflex involves stroking the sole of the foot?Babinski reflex is one of the normal reflexes in infants. Reflexes are responses that occur when the body receives a certain stimulus. The Babinski reflex occurs after the sole of the foot has been firmly stroked.
What is the Babinski reflex called?The Babinski reflex — also called the plantar reflex — is a response to stimulation of the bottom of the foot. It can help doctors evaluate a neurological problem in people over age 2. If your child has this reflex and doesn't show any other signs of neurological problems, however, there's probably no need to worry.
What type of reflex is the plantar reflex?Superficial Reflexes
The plantar reflex is the most common superficial reflex examined. A stimulus (usually by the handle end of a reflex hammer) is applied on the sole of the foot from the lateral border up and across the ball of the foot. A normal reaction consists of flexion of the great toe or no response.
What is a Babinski's reflex used for?The Babinski reflex tests the integrity of the corticospinal tract (CST). The CST is a descending fiber tract that originates from the cerebral cortex through the brainstem and spinal cord. Fibers from the CST synapse with the alpha motor neuron in the spinal cord and help direct motor function.
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