The symptoms of left posterior lumbar pain in men: 1, may be due to lumbar disc protrusion, compression of nerves resulting in left posterior lumbar pain. 2, may also be caused by lumbar dorsal myofasciitis, third lumbar transverse synovial syndrome, lumbar strain of the left posterior lumbar back, etc., appearing local muscle tension, restricted activity, symptoms significantly aggravated after exertion. 3, there are also diseases of the urinary system, such as ureteral calculi on the left side, kidney stones on the left side, etc. can cause left posterior lumbar pain symptoms, manifested as renal colic, which can radiate to the perineum. For example, ureteral stones on the left side, kidney stones on the left side can cause pain symptoms in the left posterior lumbar region of men, manifesting as renal colic, which can radiate to the perineum, accompanied by symptoms such as meatus hematuria. Therefore, if the symptoms of male left posterior lumbar pain appear, if the symptoms do not improve after bed rest, local topical blood circulation, anti-inflammatory and analgesic drugs and physiotherapy, you should promptly go to a regular hospital, improve the necessary auxiliary examinations and combine with specialist examination, and choose a reasonable treatment method after a clear diagnosis, so that the disease of male left posterior lumbar pain can be treated promptly and effectively.