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 seen to have …

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 central nervous …

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 muscle, activating …

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 the most commonly …

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 and visceral …

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 tendon …

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) reflex.

Dec 21, 2025 · 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 thigh muscle, all of …

The patellar reflex or knee-jerk is a stretch reflex. Striking the patellar tendon with a tendon hammer just below the patella stretches the quadriceps tendon.

Aug 14, 2025 · The knee jerk reflex, also known as the patellar reflex, is an involuntary response where the lower leg kicks forward after a tap just below the kneecap. This quick muscle contraction is a type …