Name of test



Patellar reflex (knee jerk)

What it tests



Whether the L4 nerve root is intact

How to do it


  • In the sitting position, the patient allows his/her knee to be flexed without contracting the muscle.
  • The clinician taps the patellar tendon with a reflex hammer just above the tibial tuberosity.

The normal response



Normal patellar reflex (knee jerk) of 1-2/4

What it means if not normal



Disruption in the monosynaptic reflex arc

Comments


Citations






Hoppenfeld, Stanley. Orthopaedic Neurology. Philadelphia: J.B. Lippincott Co., 1997.

K. Anderson, J. Hall. Sports Injury and Management: Philadelphia: Williams & Wilkins,1995.

Reider, Bruce. The Orthopaedic Physical Examination, 2nd Ed.: Philadelpiha: Elsevier Saunders, 2005.

Unknown macro: {cite}

Figures