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why do we have deep tendon reflexes

by Mr. Linwood Kertzmann Published 2 years ago Updated 1 year ago
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Tendon reflexes are important because they provide an objective sign indicating abnormality and some indication as to the level of the abnormality. Reflexes can be graded as absent, obtainable with reinforcement (see below), reduced, normal, increased and increased with clonus.

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What are deep tendon reflexes?

Deep tendon reflexes demonstrate the homeo- stasis between the cerebral cortex and the spinal cord. When these reflexes are disrupted, hyperreflexia (dis- ease induced) or hyporeflexia/areflexia (drug

Can deep tendon reflexes be used in screening exams?

All of the commonly used deep tendon reflexes are presented here in a group. In a screening examination you will usually find it more convenient to integrate the reflex examination into the rest of the examination of that part of the body; that is, do the upper extremity reflexes when examining the rest of the upper extremity.

What are hypoactive tendon reflexes?

Hypoactive tendon reflexes indicate developing magnesium toxicity ( Clinical management and outcome of eclampsia at Rajavithi Hospital. Magnesium sulfate in eclampsia and pre‐eclampsia. Magnesium sulfate as an anticonvulsant in eclampsia.

Is the Myotatic reflex the same as the deep tendon reflex?

Hence, the myotatic (muscle-stretching) reflex is the same as the stretch reflex, and both terms are synonymous with deep tendon reflex. It would be correct to say deep reflex, tendon reflex, myotatic reflex, or stretch reflex, but it is actually redundant to say “deep tendon reflex.”

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Why do we do deep tendon reflexes?

The DTR is used to assess the integrity of the motor system. They also provide information on the condition of upper and lower motor neurons. The DTR depends on the integrity of both the upper motor neuron and the lower motor neuron.

What is the function of a tendon reflex?

Tendon reflex (or T-reflex) is a feedback mechanism that controls increasing muscle tension by causing muscle relaxation before tension force becomes so great it may damage the muscle.

What does absence of deep tendon reflexes mean?

If your doctor taps on a tendon and there isn't a reflexive movement in the muscle, it's a sign of a health issue. Usually, absent reflexes are caused by an issue with the nerves in the tendon and muscle. You may have other muscle symptoms along with areflexia, like weakness, twitching, or atrophy.

Where are deep tendon reflexes?

5:059:04Deep Tendon Reflex Examination for Nursing Head to Toe Assessment of ...YouTubeStart of suggested clipEnd of suggested clipNow we're going to check the tricep deep tendon and it is located on the back of the arm right aboveMoreNow we're going to check the tricep deep tendon and it is located on the back of the arm right above the elbow.

What do deep tendon reflexes assess quizlet?

A reflex is a motor response to a sensory stimulation that is used in an assessment to observe the integrity of the nervous system. They elicit a muscle contraction when the muscle's tenon is stimulated. The patient should be relaxed.

Why dont you have a knee reflex?

The normal response is a 'knee jerk'. This is an example of a reflex, which is an involuntary muscular response elicited by the rubber hammer tapping the associated tendon. When reflex responses are absent this could be a clue that the spinal cord, nerve root, peripheral nerve, or muscle has been damaged.

Why do we have knee reflexes?

When we stand upright, our muscles constantly stretch and contract slightly, just to keep us balanced. The knee jerk reflex is part of this system.

What is reflex exam?

Reflex Exam (Deep Tendon Reflexes) The reflex exam is fundamental to the neurological exam and important to locating upper versus lower motor neuron lesions. There are five deep tendon reflexes and a number of superficial and visceral reflexes covered here.

Can you evaluate reflexes?

Reflexes are useful for the general internist to perform, but you can’t evaluate them if …. You don’t have a hammer. You don’t use proper technique, in which case the reflex will appear to be absent when it is present. If you don’t know what abnormalities to expect and what they mean.

What reflexes are stimulated in the presence of hyperactive biceps?

The usual pattern is for only the brachioradialis reflex to be stimulated. But in the presence of a hyperactive biceps or finger jerk reflex, these reflexes may be stimulated also. Finger Jerk. Have the patient gently curl his fingers over your index finger, much as a bird curls its claws around the branch of a tree.

What is a stretch reflex?

A stretch reflex is the contraction of a muscle in response to stretching of muscle spindles, which are receptor s that lie in parallel with extrafusal muscle fibers. The reflex is composed of a two-neuron arc. The afferent neuron, whose cell body is in a sensory ganglion, innervates the spindle.

What is hyperactive reflex?

When a reflex is hyperactive, that muscle often will respond to the testing of a nearby muscle. A good example is reflex activity of a hyperactive biceps or finger reflex when the brachioradialis tendon is tapped. This is termed "overflowing" of a reflex.

What does 4+ mean in reflexology?

4+ = a tap elicits a repeating reflex (clonus); always ab normal. Whether the 1 + and 3 + responses are normal depends on what they were previously, that is, the patient's reflex history; what the other reflexes are; and analysis of associated findings such as muscle tone, muscle strength, or other evidence of disease.

What does hyperreflexia mean?

Hyperreflexiarefers to hyperactive or repeating (clonic) reflexes. These usually indicate an interruption of corticospinal and other descending pathways that influence the reflex arc due to a suprasegmental lesion, that is, ...

Which neuron innervates the spindle?

The afferent neuron, whose cell body is in a sensory ganglion, innervates the spindle. When the muscle spindle is stretched, this neuron fires and monosynaptically excites alpha motoneurons in the anterior horn of the spinal cord. This alpha motoneuron is the second neuron; it supplies the muscle that is being tapped or transiently stretched.

Which neuron innervates the muscle or Golgi tendon organ associated with the muscles?

The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon organ associated with the muscles; the efferent neuron is an alpha motoneuron in the anterior horn of the cord.

What is the reflex of a deep tendon?

Deep Tendon Reflexes. In a normal person, when a muscle tendon is tapped briskly, the muscle immediately contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle. The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon o ….

What happens when a muscle is tapped?

In a normal person, when a muscle tendon is tapped briskly, the muscle immediately contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle. The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon organ associated with the muscles;

What does hyperreflexia mean?

Hyperreflexiarefers to hyperactive or repeating (clonic) reflexes. These usually indicate an interruption of corticospinal and other descending pathways that influence the reflex arc due to a suprasegmental lesion, that is, ...

Which part of the brain controls the sensory input of the muscle spindles?

The cerebral cortex and a number of brainstem nuclei exert influence over the sensory input of the muscle spindles by means of the gamma motoneurons that are located in the anterior horn; these neurons supply a set of muscle fibers that control the length of the muscle spindle itself.

Which neuron innervates the muscle?

In a normal person, when a muscle tendon is tapped briskly, the muscle immediately contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle. The afferent neuron whose cell body lies in ...

What are deep tendon reflexes?

Deep tendon reflexes demonstrate the homeostasis between the cerebral cortex and the spinal cord. When these reflexes are disrupted, hyperreflexia (disease induced) or hyporeflexia/areflexia (drug induced) occurs. Although nurses perform deep tendon reflex assessments regularly, it is difficult to incorporate theoretical principles in these assessments because of scant medical literature, a lack of nursing research, and time constraints in nursing programs. These conditions usually result in one-on-one training, causing reduced consistency. A comprehensive examination assists the clinician to apply theoretical principles, develop expert technique, and serve as a catalyst for clinical research.

What is brisk reflex?

brisk reflexes (hyperreflexia) are the result of an irritable. cortex and indicate central nervous system involvement. Whenever there is central nervous system involvement, the potential for seizure exists. Whenever the potential for. seizure exists, the need for magnesium therapy should be. evaluated.

Which muscle is linearly correlated with the rate of muscle stretch?

2. Under conditions of constant muscle contraction, the myotatic reflex in soleus and lateral gastrocnemius muscles is linearly and highly correlated with the rate of muscle stretch. The slope of this curve characterizes part of the reflex arc "gain.".

Which part of the brain provides continuous signals that inhibit or. reduce limb movement?

The cere-. bral cortex provides continuous signals that inhibit or. reduce limb movement, and the spinal cord provides sig-. nals that facilitate or cause limb movement. Fundamen-. tally, the tendon reflex response demonstrates a balance. of signals between the cerebral cortex and the spinal cord.

Is myotatic reflex the same as stretch reflex?

Hence, the myotatic (muscle-. stretching) reflex is the same as the stretch reflex, and. both terms are synonymous with deep tendon reflex. It. would be correct to say deep reflex, tendon reflex, myotatic reflex, or stretch reflex, but it is actually redun-. dant to say “deep tendon reflex.”.

What are deep tendon reflexes?

Deep tendon reflexes demonstrate the homeo‐stasis between the cerebral cortex and the spinal cord. When these reflexes are disrupted, hyperreflexia (disease induced) or hyporeflexia/areflexia (drug induced) occurs. Although nurses perform deep tendon reflex assessments regularly, it is difficult to incorporate theoretical principles in these assessments because of scant medical literature, a lack of nursing research, and time constraints in nursing programs. These conditions usually result in one‐on‐one training, causing reduced consistency. A comprehensive examination assists the clinician to apply theoretical principles, develop expert technique, and serve as a catalyst for clinical research.

What is the myotatic reflex?

The deep tendon reflex is also known as the myotatic reflex or the stretch reflex ( Gilman & Newman, 1996; Hallet, 1993; Molavi, 1999; Myklebust, 1990 ). Myo is derived from the Greek word mys, which means muscle. The word tatic comes from tasis and literally means stretching ( Thomas, 1997 ). Hence, the myotatic (muscle-stretching) reflex is the same as the stretch reflex, and both terms are synonymous with deep tendon reflex. It would be correct to say deep reflex, tendon reflex, myotatic reflex, or stretch reflex, but it is actually redundant to say “deep tendon reflex.”

What causes an absent reflex response in obstetric patients?

These include regional block anesthesia and magnesium administration. If physiological alterations occur at the level of the spinal cord (i.e., as a result of regional anesthesia), the impulse from the stretched muscle reaches the spinal cord yet cannot jump across to the neuron and send the “go back and move” impulse back down to the muscle. For this reason, we see altered reflexes after initiation of an epidural or spinal block.

What is the reflex scale?

First published by a group of physicians in the 1950s for Mayo Clinic staff, this scale uses a complicated 9-point rating scheme ranging from − 4 to + 4, with normal reflexes reported as a zero (see Table 1 ). Facilities around the world use this scale, although it may not be widely used in obstetric practice.

What is hyperreflexia in preeclampsia?

The cortex cannot send inhibitory impulses to the spinal cord. When the spinal cord does not receive sufficient restraint from the cerebral cortex, the reflex arc processes only facilitory impulses and hyperreflexia results. Therefore, brisk reflexes (hyperreflexia) are the result of an irritable cortex and indicate central nervous system involvement. Whenever there is central nervous system involvement, the potential for seizure exists. Whenever the potential for seizure exists, the need for magnesium therapy should be evaluated. That is how we associate DTR assessment with preeclampsia.

What is a deep tendon reflex?

Deep tendon reflexes, more properly referred to as muscle stretch reflexes, are an integral part of the neurological examination. A stretch reflex is an involuntary reaction of a muscle to being passively stretched by percussion of the tendon.

What scale is used to grade deep tendon reflexes?

The scale used at WSCC clinics is the National Institute of Neurological Disorders and Stroke (NINDS 1991) muscle stretch reflex scale. The reflex is graded based on the amplitude of the response. The only reflex that is always abnormal is clonus. The “+” after the number is to distinguish from muscle testing, it is not a meant as a “plus” or “minus” in the traditional sense.

What is reinforcement technique?

For example, in the case of a lower extremity reflex, the patient interlocks fingers together and pulls when cued by the practitioner. A reinforcement technique for an upper extremity reflex is to have the patient contract a lower extremity muscle (Delwaide 1981) or clench the jaw (Tarkka 1983), while the practitioner taps the tendon.

Is a clonus a reflex?

Exaggerated reflex or clonus: This suggests an upper motor neuron lesion above the root at that level. Normally, in children, upper extremity reflexes are stronger than lower extremity reflexes. (Orient 2005) Increased reflexes are often normal, especially when symmetrical; clonus should never be interpreted as normal.

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1.Deep Tendon Reflexes: The What, Why, Where, and How …

Url:https://www.jognn.org/article/S0884-2175(15)34063-6/fulltext

15 hours ago  · Why do we have deep tendon reflexes? Deep tendon reflex also usually refers to this sense. A deep tendon reflex is often associated with muscle stretching. Tendon reflex tests are used to determine the integrity of the spinal cord and peripheral nervous system, and they can be used to determine the presence of a neuromuscular disease. Click to see full answer.

2.Videos of Why Do We Have Deep Tendon Reflexes

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1 hours ago Reflex Exam (Deep Tendon Reflexes) The reflex exam is fundamental to the neurological exam and important to locating upper versus lower motor neuron lesions. There are five deep tendon reflexes and a number of superficial and visceral reflexes …

3.Deep Tendon Reflexes - Stanford Medicine 25

Url:https://stanfordmedicine25.stanford.edu/the25/tendon.html

8 hours ago These usually indicate an interruption of corticospinal and other descending pathways that influence the reflex arc due to a suprasegmental lesion, that is, a lesion above the level of the spinal reflex pathways. By convention the deep tendon reflexes are graded as follows: 0 = no response; always abnormal.

4.Deep Tendon Reflexes - Clinical Methods - NCBI Bookshelf

Url:https://www.ncbi.nlm.nih.gov/books/NBK396/

2 hours ago  · Several types of reflexes can be tested as part of a physical examination and these all reveal something about the status of the elements of the nervous system that contribute to their functioning. They have been used for over a century as part of a routine neurological examination due to their safety, low cost, predictive value, and ability to be performed rapidly, …

5.Deep Tendon Reflexes - StatPearls - NCBI Bookshelf

Url:https://www.ncbi.nlm.nih.gov/books/NBK531502/

16 hours ago These usually indicate an interruption of corticospinal and other descending pathways that influence the reflex arc due to a suprasegmental lesion, that is, a lesion above the level of the spinal reflex pathways. By convention the deep tendon reflexes are graded as follows: 0 = no response; always abnormal. 1+ = a slight but definitely present response; may or may not be …

6.Deep Tendon Reflexes - PubMed

Url:https://pubmed.ncbi.nlm.nih.gov/21250237/

19 hours ago  · The aroused receptors initiate the reflex arc, causing the muscle to move. Deep reflexes include patellar, Achilles, plantar, triceps, and biceps reflexes. With superficial reflexes, light stroking on the skin stimulates the cutaneous tissue, which initiates the reflex arc and causes the underlying muscle to twitch.

7.Deep Tendon Reflexes: The What, Why, Where, and How …

Url:https://www.researchgate.net/publication/10735751_Deep_Tendon_Reflexes_The_What_Why_Where_and_How_of_Tapping

6 hours ago Deep Tendon Reflexes (DTR) Deep tendon reflexes, more properly referred to as muscle stretch reflexes, are an integral part of the neurological examination. A stretch reflex is an involuntary reaction of a muscle to being passively stretched by percussion of the tendon. Although the reflex has a sensory and motor component, deep tendon reflex testing

8.Deep Tendon Reflexes: The What, Why, Where, and How …

Url:https://www.sciencedirect.com/science/article/pii/S0884217515340636

4 hours ago Deep tendon reflexes demonstrate the homeo- stasis between the cerebral cortex and the spinal cord. When these reflexes are disrupted, hyperreflexia (dis- ease induced) or hyporeflexia/areflexia (drug induced) occurs. Although nurses perform deep ten- don reflex assessments regularly, it is difficult to incor-

9.Deep Tendon Reflexes - University of Western States

Url:https://ftp.uws.edu/udocs/public/CSPE_Protocols_and_Care_Pathways/Protocols/Deep_Tendon_Reflexes.pdf

15 hours ago

10.Deep Tendon Reflexes: The What, Why, Where, and …

Url:https://www.jognn.org/article/s0884-2175(15)34063-6/pdf

23 hours ago

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