The kidneys are a pair of organs, shaped like lima beans, found in the back of the body cavity. They touch the back muscles and are located under the lower ribs, near the liver.
Because the right side of the liver is larger, the right kidney sits lower in the body than the left kidney. The kidneys are positioned outside of the parietal peritoneum, the membrane that encloses the majority of the body's organs. Layers of fat and connective tissue keep the kidneys from moving, and protect them from damage.
Someone experiencing kidney pain would feel it in the back or the side of her body; however, the kidneys are not usually the cause of the pain. Possible causes of kidney pain include bleeding inside of the kidney, blood clots in the kidney veins or a urinary tract infection. It is common to have both kidney pain and a fever.
The kidney's main job is to filter waste out of the blood and convert it to urine. Each kidney is connected to the bladder with a ureter, a tube that transports urine from the kidney to the bladder so that the urine can be excreted. Other functions of the kidney include maintaining electrolyte balance and producing hormones.