It is possible for left-sided back pain to be caused by a problem with one or more internal organs, such as from the kidney or colon.
Several common internal causes of lower left back pain include:
Lower left back pain from a kidney stone may be felt when a stone moves inside the left kidney, or moves through the ureters, thin tubes connecting the kidneys to the bladder. Other symptoms include pain with urination, difficulty urinating despite a persistent need to do so, blood in the urine, and nausea and/or vomiting.
An infection in the left kidney can cause dull or intense lower left back pain. Kidney infections usually start in the urinary tract and bladder, and from there can spread to the kidneys, causing local inflammation and pain in the kidney. Additional symptoms may include fever, nausea and/or vomiting, and painful or stinging urination. Pain is typically felt next to the spine above the hip, and typically worsens with movement or pressure.
Fibroids and endometriosis, two common conditions in women, can cause lower left back pain. Pain from endometriosis is usually sporadic, sharp and stabbing, and is caused by excess uterine tissue growing outside the uterus. Other symptoms many include abdominal pain, fatigue, and severe pain with menstruation. Fibroids—typically benign masses growing in the uterus—can cause lower left back pain, as well as abnormal menstruation, frequent urination, and pain with intercourse.
An inflammatory bowel disease, ulcerative colitis is marked by persistent inflammation mostly in the large intestine, also called the colon. Inflammation usually causes chronic digestive issues such as diarrhea, rectal pain, and weight loss. Abdominal cramping is a common symptom of ulcerative colitis, causing sharp back and abdominal pain on one or both sides of the body.
One-sided lower back pain can occur during pregnancy as the baby develops and the mother’s body accommodates. Pain can vary from a dull, constant ache to a sharp, stabbing pain. Exercise, stretching, rest, and some complementary therapies can help ease the pain.
This condition involves inflammation of the pancreas, which may cause upper abdominal pain that spreads to the lower left quadrant of the back. Patients may describe the pain as a dull sensation that may be aggravated by eating, especially foods high in fat.
A thorough diagnostic process by a qualified health professional should check for the above, and additional, possible causes of lower back pain. Sometimes, additional testing such as x-rays, CT scans, and/or blood tests may be recommended. It is important to seek prompt medical attention if the above conditions are suspected.