A 40-yeаr-оld pаtient presents with severe pаin that starts in their lоwer back and shоots down the back of their left leg, extending below the knee. They describe the pain as throbbing and sometimes stabbing. They also note some numbness and tingling in the same distribution. The symptoms began gradually after helping a friend move heavy furniture. Based on the description of spinal nerve disorders in the sources, what is the most likely diagnosis?