Numbness of the left lateral calf may be caused by physiological factors, such as prolonged compression of the left calf during sleep; it may also be caused by pathological factors such as lumbar intervertebral disc herniation and pyriform muscle syndrome.
1. Physiological factors: the patient’s incorrect posture during sleep at night leads to extrusion of the calf area, thus affecting the blood circulation of the calf area and producing numbness.
2. Pathologic factors:
(1) Lumbar intervertebral disc herniation: due to different degrees of degenerative changes in the lumbar intervertebral disc, it leads to irritation or compression of the adjacent spinal nerve roots, and produces lumbar pain, which may be accompanied by symptoms such as numbness and pain in one side of the lower limbs or in both lower limbs.
(2) Piriformis syndrome: due to the injury of the piriformis muscle, stimulation or compression to the sciatic nerve and cause one side of the buttock leg numbness or pain, which can be manifested as the symptom of numbness of the left lateral calf.
Numbness of the left lateral calf, after excluding physiological factors, should promptly consult the doctor to identify the cause and treatment.