Sciatica generally causes changes in six aspects. The first is pain, which mainly occurs along the distribution area of the sciatic nerve, including the back of the thigh, the posterior and lateral sides of the calf, and the lateral side of the foot and sole. I have seen a patient with severe sciatica who had to stay in bed with his head down and buttocks up to minimize spinal canal pressure, finding some relief only in this position. The second change is a decrease in muscle strength, which can even lead to muscle atrophy. The third aspect involves the pathway of the sciatic nerve, including the exit of the piriformis muscle, with tenderness and percussion pain along the course of the nerve. The fourth aspect includes symptoms of sciatic nerve traction, which involves positive results in straight leg raise tests and cross-legged tests. The fifth point is a weakened or absent Achilles reflex, due to the sciatic nerve's innervation of the muscles on the back of the thigh, leading to a decrease or disappearance of the Achilles reflex. The sixth point is abnormal sensations in the area innervated by the sciatic nerve, including reduced or lost sensations or mild sensory disturbances.