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patellar reflex
patellar reflex The patellar reflex, or knee-jerk, is a tendon reflex in which the knee suddenly straightens because the quadriceps muscle contracts, usually after the patellar tendon is tapped while the lower leg hangs freely.
The patellar reflex, or knee-jerk, is a tendon reflex in which the knee suddenly straightens because the quadriceps muscle contracts, usually after the patellar tendon is tapped while the lower leg hangs freely. In historical psychological and neurological use, it was valued as a convenient sign of the state of the reflex mechanism and was also studied for changes linked with attention and fatigue.