Urinary system: e.g. acute and chronic pyelonephritis, kidney tumours, kidney stones, ureteral stones, renal tuberculosis, renal prolapse, perinephric abscess, prostatitis, prostate tumours, etc.
Digestive system: e.g. peptic ulcers, chronic cholecystitis, gallstones, pancreatic cancer, rectal cancer, etc.
Gynecological disorders: e.g. adnexitis, uterine corporitis, retroverted uterus, pelvic tumour, uterine prolapse, pelvic congestion, menstrual tension, etc.
Others: such as subdiaphragmatic abscesses and retroperitoneal tumours can also cause back pain.