The patellar reflex, also called the knee reflex or knee-jerk, is a stretch reflex which tests the L2, L3, and L4 segments of the spinal cord. Many animals, most significantly humans, have been …

In reaction these muscles contract, and the contraction tends to straighten the leg in a kicking motion. Exaggeration or absence of the reaction suggests that there may be damage to the …

Jul 27, 2025 · The patellar reflex begins when a healthcare professional taps the patellar tendon, located just below the kneecap, with a reflex hammer. This tap stretches the quadriceps …

Nov 8, 2025 · During this reflex, a tap on the patellar tendon just below the kneecap triggers a rapid contraction of the quadriceps muscle, causing the lower leg to kick outward. While the …

The reflex exam is fundamental to the neurological exam and important to locating upper versus lower motor neuron lesions. There are five deep tendon reflexes and a number of superficial …

The patellar reflex, also known as the knee-jerk reflex, is a monosynaptic spinal reflex that evaluates the integrity of the L2-L4 spinal cord segments and the femoral nerve. It is one of …

Dec 5, 2025 · The patellar reflex is contraction of the quadriceps femoris muscle, with resulting extension of the knee, in response to percussion of the patellar tendon. A firm tap on the …

3 days ago · This is a test of the connection between the sensory nerves attached to stretch receptors in the muscle, the spinal cord, and the motor neurons running from the cord to the …

In this lab, students will determine the response time, conduction velocity (speed), and amplitude (strength) of two stretch reflexes: the Achilles reflex at the ankle and the patellar (knee-jerk) …

The Patellar reflex is a neurological reflex that occurs when the patellar tendon is tapped, resulting in the extension of the knee. It is associated with the fourth lumbar vertebra (L4) and is a …