Jendrassik Maneuver

Jendrassik Maneuver
Medicine Question Bank

What is Jendrassik Maneuver?

Jendrassik maneuver is a medical maneuver –

Patient clenches the teeth, flexes both sets of fingers into a hook-like form, and interlocks those sets of fingers together.

When patients patellar reflex is a decreased or absent Jendrassik maneuver helps to bring out a response or a larger response. That indicates some conscious/supraspinal inhibition which is again inhibited by Jendrassik Maneuver so it brings a larger response of reflex.

Why we need Jendrassik Maneuver ?

According to the NINDS scale –

grade 1 reflexes describe reflexes made conspicuous by reinforcement maneuvers

grade 0 reflexes are those that are absent despite reinforcement.

We need to know what is the response which is more clear with Jendrassik Maneuver.

The most common method of reinforcing reflexes is the Jendrassik maneuver.

What is the Mechanism of Jendrassik Maneuver?

  • JM will exaggerate 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.
  • mechanism for a JM is a reduction in PSI of alpha motoneurons by Ia afferents as it is influenced by physical and not mental activity. 
Jendrassik Maneuver
Medicine Question Bank