Herniated lumbar disc knee pain may be due to nerve compression, lower limb muscle atrophy, combined with osteoarthritis and other factors. 1. Nerve compression: lumbar disc herniation can cause compression of the spinal cord and nerve roots, resulting in numbness and pain in the lower limb region, and neuromuscular pain, which can involve pain in the knee joint area. 2. Lower limb muscle atrophy: with the further development of lumbar disc herniation, the nerve compression symptom worsens, which can lead to the loss of nerve nutrition of the lower limb muscles, resulting in lower limb muscle atrophy, which can also cause pain in the knee joints, and even lead to joint weakness and activity limitation. 3. Combined with osteoarthritis: degenerative diseases will occur in all joints of the body of the elderly, when combined with osteoarthritis, there will be knee pain, weakness, and joint movement disorders and other symptoms. Herniated lumbar disc knee pain, there may be other causes, it is recommended that the patient timely hospital consultation, clear causes for standardized treatment.