Low back pain in 9 year olds is often caused by congenital anomalies such as congenital isthmic fracture, congenital lumbar hypoplasia, congenital lumbar occult fracture, or sacralization of the lumbar spine, which can often lead to low back pain, and should be diagnosed early with X-rays, CT, and MRI. If the isthmus of the lumbar spine is severely cracked, early surgery may also be considered to fix the lumbar spine to prevent slippage and reduce pain. Less common causes are tuberculosis or tumors of the lumbar spine, both of which are relatively rare in children, but if the cause of chronic back pain cannot be identified, both tests should be performed for early diagnosis and treatment.