Back Pain and Flank Pain

It is sometimes hard to tell the difference between back pain that is caused by a bone or muscle problem and back pain (flank pain) that is caused by a kidney or bladder infection or a kidney stone.

Back pain that is caused by a bone or muscle problem:

  • Occurs in the lower back; below the waist; or in the upper back, over the spine or between the shoulder blades.
  • Gets worse when a person moves.
  • Gets better when a person rests.

Flank pain that is caused by a kidney infection or a kidney stone:

  • Is pain felt just below the rib cage and above the waist. Flank pain can be on one or both sides of the back.
  • May spread to the bladder area or genitals.
  • Gets worse as the bladder fills.
  • Does not get worse when a person moves.

Flank pain with fever and urinary symptoms may mean a kidney infection (pyelonephritis) is present.

Current as of: March 21, 2017

Author: Healthwise Staff

Medical Review: William H. Blahd, Jr., MD, FACEP - Emergency Medicine & Adam Husney, MD - Family Medicine & A. Evan Eyler, MD, MPH - Family Medicine, Psychiatry