Persistent pain or stiffness throughout the spine, from the base of the neck to the tailbone. Acute, localized pain in the neck, upper or lower back, especially after lifting heavy objects or performing other strenuous activities. Chronic pain in the middle or lower back, especially after sitting or standing for a long time. Back pain radiates from the lower back to the buttocks, down the back of the thigh, to the calf and toes. Inability to stand upright without pain or muscle spasms in the lower back.