Lumbar disc herniation is a more common type of spinal neurological disease in clinical practice. Patients with lumbar disc herniation mostly present with lumbar pain in the early stage, i.e., lumbar pain is aggravated when sitting, bending, coughing, sneezing, but reduced after lying in bed, or discogenic lumbar pain, in addition to lower limb symptoms, such as numbness, pain, soreness and coldness in the lower limbs, and in severe cases, not only compression of nerve roots, but also compression of the cauda equina nerve. In severe cases, not only the nerve roots are compressed, but also the cauda equina nerve, resulting in symptoms such as urinary and fecal dysfunction and even incontinence.
Most scholars believe that the abnormal sensation in the lower limbs of patients with lumbar disc herniation is caused by nerve root compression and irritation, which mainly manifests as numbness, coldness and chilliness in the posterior and lateral side of the affected lower limbs, and sometimes anthroposis and burning sensation; some scholars also believe that the coldness in the lower limbs of a few patients with disc herniation is related to sympathetic nerve stimulation.
When a lumbar disc herniates, it stimulates the sympathetic nerves in the paravertebral area, reflexively causing contraction of the vascular walls of the lower extremities, which in turn leads to coldness” in the lower extremities. It is also believed that pain and numbness or hypoesthesia in the lower limbs are caused by nerve compression, while pain is caused by inflammatory stimulation of the nerve roots, and sensory impairment and coldness in the lower limbs are manifestations of abnormal conduction of nociceptive and therapeutic neurons in the nervous system.”