“Motor testing also helps identify which nerve root may be the source of the problem. If there is weakness in quadriceps strength, it indicates that the L4 nerve root may be affected. Weakness on dorsiflexion indicates that the L5 nerve root may be affected, whereas plantar flexion weakness is indicative of an S1 radiculopathy (Fig. 2-13). A good way to help remember these is as follows. “Quad” means four—L4. Bending five toes toward the patient (dorsiflexion) tests L5. Pressing down on the gas (plantar flexion) of a new S1 Porsche tests S1. A positive straight-leg test is a nonspecific sign for lumbar disc herniation. The patient experiences pain in the back when”