Why does the Jendrassik maneuver influence the reflex response?

The JM will heighten (exaggerate) lower limb tendon reflexes by countering some of the normal descending inhibition the brain sends to the reflex arc. It can also help prevent conscious inhibition of the reflex. This is why tendon reflexes in stroke and other UMNL patients have increased reflexes.

How is the Jendrassik maneuver useful?

The Jendrassik maneuver will heighten (exaggerate) the patellar (knee-jerk) reflex by countering some of the normal descending inhibitory brainstem inputs to reflex arc interneurons. apart, using as much force as can be generated without breaking the interlock.

Is the patellar reflex enhanced or inhibited during Jendrassik maneuver?

Is the patellar reflex inhibited or enhanced by voluntary muscle activity in the quadriceps? The Jendrassik maneuver- isometric contractions in another muscle group should enhance the response of the reflex. Often, this is used as a way to distract the patient and relax the muscles in the quadriceps.

What can you say about simple reflexes given your results from the Jendrassik Manoeuvre?

What can you say about “simple” reflexes, given your results from the Jendrassik maneuver? In general, a simple reflex will activate neuronal pathways. However, the Jendrassik maneuver differs in that it is also affected by other nervous pathways and will activate the lower motor neurons in the spinal cord. 3.

What effect did the Jendrassik maneuver have on the amplitude of response?

The difference of the TR amplitude between the two sides in percentage of the lower value was not significant at rest and showed a marked diminution during JM. The manoeuvre caused also a net increase of the absolute values of the compound action potentials amplitude of both reflexes.

What does reflex testing tell us?

If you think you have brisk reflexes you can ask your doctor for a reflex test. This test helps determine how effective your nervous system is by assessing the reaction between your motor pathways and sensory responses. During the test, your doctor may tap your knees, biceps, fingers, and ankles.

What causes knee jerk?

Knee-jerk reflex, also called patellar reflex, sudden kicking movement of the lower leg in response to a sharp tap on the patellar tendon, which lies just below the kneecap.

Why is patellar reflex faster than Achilles?

Fewer neuron fibers need to be activated for the Achilles reflex as compared to the Patellar reflex. The number of muscle fibers that need to be activated in the patellar reflex to create a response is greater and therefore the response may be slower that the Achilles reflex.

What happens in Jendrassik maneuver?

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.

Did this experiment help you decide which of the factors proposed to explain fatigue are important quizlet?

Did this experiment help you decide which of the factors proposed to explain fatigue are important? Yes, there is clearly more fatigue occurring during the heaviest contractions compared to the least heavy contractions.

What mechanism can you propose for tension decrease in our pseudo fatigue experiment?

2pts. What mechanism can you propose for tension decrease in our pseudo-fatigue experiment? To maintain a certain amount of force (tension) from a muscle, the brain needs sensory feedback from receptors.

Does mental distraction affect reflexes?

Mental distraction plays no part on the reflex.

How does the Jendrassik maneuver ( JM ) work?

A response or a larger response may be observed, indicating some conscious/supraspinal inhibition. How does it work? The JM will heighten (exaggerate) lower limb tendon reflexes by countering some of the normal descending inhibition the brain sends to the reflex arc. It can also help prevent conscious inhibition of the reflex.

Why does the Jendrassik maneuver cause spinal cord disease?

4. The reflex is unusually brisk compared with reflexes from a higher spinal level, which raises the possibility of spinal cord disease at some level of the spinal cord between the segments with exaggerated reflexes and those with diminished ones.

Why is reflex amplitude asymmetric in Jendrassik maneuver?

The reflex amplitude is asymmetric, which suggests either lower motor neuron disease of the side with the diminished reflex or upper motor neuron disease of the side with exaggerated reflex. 4.

How to avoid ankle jerk with Jendrassik maneuver?

Tap the patellar tendon with the hammer and observe quadriceps contraction. Note impairment or exaggeration. Ankle jerk: S1, S2 roots. Externally rotate the patient’s leg. Hold the foot in slight dorsiflexion. Ensure the foot is relaxed by palpating the tendon of tibialis anterior. If this is taut, then no ankle jerk will be elicited.

https://www.youtube.com/watch?v=ddNr6b8cVNc