A groove in the spine of the back may be a normal phenomenon, or it may be scoliosis, peri-spinal lesions and other abnormalities. 1. Normal phenomenon: Generally speaking, the body type is relatively thin people due to its two sides of the erector spinae muscle high convex, and make the skin around the relative depression, resulting in a groove, which is a normal physiological situation. And body fat, fat more people generally will not have observed. 2. Scoliosis: when the spine is scoliotic, it will cause the back to be concave and the thorax to be deformed. 3. Lesions around the spine: when there are soft tissue lesions around the spine, downward depression around the spine may also occur. For example, if there is a severe localized burn, and the surrounding tissues produce scarring adhesions, the skin on the surface may be pulled to the internal depression, which means that the downward depression around the spine is manifested. Depression around the spine in the back is generally normal if there are no other abnormal sensations. If there is pain or other discomfort, it is recommended to go to the hospital to confirm the diagnosis.