If a doctor attempts to trigger the patellar tendon reflex and a lack of response occurs, what are potential regions where pathology might exist?
I.the brain
II.the knee
III.the spinal cord
A) only I
B) only II
C) only III
D) only II and III

Question

Quizplus · Accepted Answer

The patellar tendon reflex is a stretch reflex controlled by the spinal cord, with a sensory input from the muscle spindles in the quadriceps muscle and motor output from the femoral nerve. Therefore, if there is no response to a patellar tendon reflex, it suggests pathology in the spinal cord (option III) or the knee joint (option II). Pathology in the brain (option I) would not directly affect this reflex.

If a Doctor Attempts to Trigger the Patellar Tendon Reflex