Table of Contents
What is your patellar reflex?
knee-jerk reflex, also called patellar reflex, sudden kicking movement of the lower leg in response to a sharp tap on the patellar tendon, which lies just below the kneecap. In reaction these muscles contract, and the contraction tends to straighten the leg in a kicking motion.
What is the purpose of the patellar reflex?
The primary purpose of the patellar reflex – the stretch reflex of the quadriceps femoris muscle – is to prevent excessive stretching of the quadriceps.
What are the patellar and Achilles reflexes?
The patellar (knee) reflex is mediated by innervation from L2, L3, L4. The ankle (Achilles) reflex is mediated by innervation from S1. It is important to compare symmetry of reflexes, since patients may vary in the reaction to stimulation. Hyperreflexia is associated with upper motor neuron disease.
Why do doctors test the patellar reflex?
Medical author Dr Janice Rachel Mae explains that doctors routinely use reflex tests to check if there are any problems in the nervous system involved in movement, nerve functioning or health of the connective tissue in the knee or leg.
Where is the patellar reflex?
The patellar reflex is a deep tendon reflex, mediated by the spinal nerves from the levels L2, L3, and L4 in the spinal cord, predominantly in the root L4.
Which nerve is responsible for patellar reflex?
Although the knee jerk reflex is mediated by the L3 and L4 nerve roots, evidence exists that altered knee jerk expression may occur with exclusively L5 radiculopathy.
What nerve is tested in the patellar reflex?
The patellar tendon reflex tests the function of the femoral nerve and spinal cord segments L2-L4.
What does it mean if you don’t have a reflex in your knee?
Patellar tendon reflex. In a normal test, your knee will extend and lift your foot a little. A decreased or absent reflex may mean that there is compression in the L2, L3, or L4 region.
What nerve is tested in patellar reflex?
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.