Back cold stiffness and tightness, may be caused by physiological reasons, may also be ankylosing spondylitis, rheumatoid arthritis, fasciitis and other diseases caused. 1. Physiological reasons: If the outside air is cold, wearing thin clothes, cold air stimulation may cause reflexive muscle contraction, which leads to the phenomenon of back cold, stiff and taut. 2. Ankylosing spondylitis: it mainly affects the sacroiliac joints, spine, and the soft tissues and peripheral joints next to the spine, and it is a chronic inflammatory disease, which can lead to cold, stiff and tense back. 3. Rheumatoid arthritis: arthritis caused by hemolytic streptococcal infection, involving localized areas, may also cause the symptoms. 4. Fasciitis: aseptic inflammation of the fascia of the back may also cause the back to be cold, stiff and taut. There may be other reasons for back coldness, stiffness and tightness, it is recommended to go to the hospital in time for examination to clarify the cause of the disease.