Hello! Thank you for asking on HCM! I understand your concern and would like to explain that your symptoms radicular pain, irradiating by a possible disc displacement in your lumbar spine. A knee injury, involving the nerves would not cause pain in the thigh, or even more on your back, but it would cause pain locally or irradiating down the calf. I recommend consulting with a neurologist for a careful physical examination , a lumbar spine x ray and a nerve conduction study of the lower limbs. A lumbar CT scan may be necessary to examine better your lumbar vertebral column. Meanwhile, I would advise you to have some rest and take some painkillers like acetaminophen or ibuprofen. Hope to have been of help! Best wishes! Dr. Iliri