The lumbar spine has a lumbar plexus, which has three nerve roots coming out from lumbar 3 to sacral 1. If pressure is applied to the femoral nerve, pain in the anterior aspect of the thigh will occur. If pressure is put on the lumbar 4 and 5 nerves, there will be pain, numbness, and soreness in the area of innervation from the lateral calf to the top of the foot. All the symptoms of the nerve appear called soreness, pain, swelling, numbness, sleepiness, and in severe cases, coldness and numbness, and in more severe cases, complete loss of innervation of the nerve, i.e., loss of motor function. Patients sometimes can not hook up the big toe, if the compression of the lumbar 5 sacral 1, the head of the big toe is foot droop, when walking a lurch, this is the most mild sciatic nerve injury symptoms. Severe sciatic nerve injury will press on the cauda equina nerve of the sciatic nerve. Once the cauda equina nerve becomes symptomatic, there will be difficulty in urinating and defecating, perianal numbness, soreness and swelling, and serious incontinence, which will eventually lead to a series of abnormal problems. So, a mild disc herniation is a slight soreness, pain, swelling, and numbness, and sometimes a simple back pain ends up involving a problem that requires treatment. There is also a herniated disc in lumbar 5 sacral 1, which compresses the sacral 1 nerve root, and the sacral 1 nerve root will show abnormal reactions on the back side of the calf all the way to the bottom of the foot, or soreness, pain, swelling, numbness, and sleepiness, with severe chills, numbness, and loss of consciousness.