Westphal's sign

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).

Westphal's sign has a clinical significance used in determining neurodisorders or diseases such as:

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