The most common causes of pain on the left side of the foot are as follows: 1. It may be caused by trauma, the patient usually has a history of foot sprain or pressure or contusion, in addition to pain, it will be accompanied by local swelling, and the pain will increase when moving. 2. 3. It may be a disease of the lumbar spine, such as a herniated lumbar disc or lumbar spinal stenosis that compresses the nerve roots, resulting in nerve pulling pain, numbness and weakness in the lower limbs. In addition to the nerve pulling pain on the surface of the foot, this condition can also manifest as muscle and nerve pulling pain on the back of the calf or thigh.