And he knew the common names for caries, myopia and missing patellar reflex.
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An example of a reflex test would be the patellar reflex test.
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Westphal's sign is the clinical correlate of the absence or decrease of patellar reflex or knee jerk. Patellar reflex or knee jerk is a kind of deep or stretch reflex where an application of a stimulus to the patellar tendon such as strike by a solid object or hammer caused the leg to extend due to such stimulus causes the quadriceps femoris muscle to contract. It is named for Carl Friedrich Otto Westphal (1833-1890).C. F. O. Westphal.
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Some reflex responses, such as withdrawing the hand after touching a hot surface, are protective, but others, such as the patellar reflex ("knee jerk") activated by tapping the patellar tendon, contribute to ordinary behavior.
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Schematic representation of patellar tendon reflex (knee jerk) pathway The patellar reflex or knee-jerk (in American English knee reflex)In American English, knee-reflex is the spelling of only the adjective, not the noun. is a stretch reflex which tests the L2, L3, and L4 segments of the spinal cord.
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The Hannington-Kiff sign is a clinical sign in which there is an absent adductor reflex in the thigh in the presence of a positive patellar reflex. It occurs in patients with an obturator hernia, due to compression of the obturator nerve.Obturator hernia: embryology, anatomy, surgery. L. J. Skandalakis, P. N. Skandalakis, G. L. Colborn and J. E. Skandalakis.
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This is a reflex of proprioception which helps maintain posture and balance, allowing to keep one's balance with little effort or conscious thought. The patellar reflex is a clinical and classic example of the monosynaptic reflex arc. There is no interneuron in the pathway leading to contraction of the quadriceps muscle. Instead, the sensory neuron synapses directly on a motor neuron in the spinal cord.
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The Jendrassik maneuver to reinforce knee-jerk. The Jendrassik maneuver is a medical maneuver wherein the patient clenches the teeth, flexes both sets of fingers into a hook-like form, and interlocks those sets of fingers together. The tendon below the patient's knee is then hit with a reflex hammer to elicit the patellar reflex. The elicited response is compared with the reflex result of the same action when the maneuver is not in use.
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Ultimately, an improper patellar reflex may indicate an injury of the central nervous system. The sensory input from the quadriceps also activates local interneurons that release the inhibitory neurotransmitter glycine onto motor neurons of antagonist muscles, blocking their stimulation (in this case the hamstring muscles). The relaxation of the opposing muscle facilitates (by not opposing) the extension of the lower leg. In lower animals reflex interneurons do not necessarily reside in the spinal cord, for example as in the lateral giant neuron of crayfish.
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Reflex arc demonstrated When a reflex arc in an animal consists of only one sensory neuron and one motor neuron, it is defined as monosynaptic, referring to the presence of a single chemical synapse. In the case of peripheral muscle reflexes (patellar reflex, achilles reflex), brief stimulation to the muscle spindle results in contraction of the agonist or effector muscle. By contrast, in polysynaptic reflex pathways, one or more interneurons connect afferent (sensory) and efferent (motor) signals. All but the most simple reflexes are polysynaptic, allowing processing or inhibition of polysynaptic reflexes within the brain.
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Goldstein's holistic approach is described in his book, The Organism. Rather than looking at certain phenomena, such as the patellar reflex, as singular events, Goldstein tried to understand them as components of a holistic organism. Although he believed it was possible that reflexes could exist by themselves, Goldstein's approach postulated that they always exist in concurrence with another process in the body. While hitting the kneecap with a rubber hammer or testing the pupillary response might seem to be a simple example of an isolated reflex, Goldstein argued that a holistic approach would be necessary to fully understand what the body is experiencing.
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When evaluating ataxic disorders and their treatments, there are numerous tests that a neurologist may perform.Tests may be evaluated individually or follow a scale for evaluating the ataxia. A cerebellar exam may include saying phrases with many consonants to detect scanning speech, detecting horizontal gaze nystagmus by following a finger with the eyes, performing rapid alternating movements like rotating a hand from palm to back repeatedly, testing the Holmes rebound phenomenon, and testing patellar reflex for hypotonia or hypertonia. Common scales include the International Cooperative Ataxia Rating Scale (ICARS) and Scale for the Assessment and Rating of Ataxic Disorders (SARA) for evaluating the severity of ataxia as a symptom.
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A reflex arc is a neural circuit that creates a more or less automatic link between a sensory input and a specific motor output. Reflex circuits vary in complexity—the simplest spinal reflexes are mediated by a two-element chain, of which in the human body there is only one, also called a monosynaptic reflex (there is only one synapse between the two neurones taking part in the arc: sensory and motor). The singular example of a monosynaptic reflex is the patellar reflex. The next simplest reflex arc is a three-element chain, beginning with sensory neurons, which activate interneurons inside of the spinal cord, which then activate motor neurons.
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