Question

What type of physical assessment uses the reflex hammer?

Answer 1

Ah, the Patellar Reflex....

Explanation:

Reflexes are meant to keep the body from harm as much as possible.

That means that sometimes it would take too long for a signal to travel up the spine, be processed by the brain and travel back down the spinal chord to the muscles that need to be activated.

Therefore a shortcut, also known as a reflex arc, is used:

The sequence:
- Signal A activates sensor (Afferent Nerve Fibre) B;
- Signal travels up the sensor to the Spinal Column (C);
- Once arrived the signal will travel up the Spinal Chord so the brain will become aware of the sensation, but it will also be rerouted back via a short interneuron (D) to Efferent (motor)neuron E, which will activate the reflex in muscle F.....

This process takes place in/around L3 , the third Lumbar vertebrae.
The test is done to diagnose any problems, either the loss or decrease of the reflex, or a resulting oscillation of the leg (pendular reflex). This can be an indication of problems in the Cerebellum, the "Engine Room" of the body...

Picture: courtesy https://en.wikipedia.org/wiki/Reflex_arc