The flanks are an anatomical region defining a specific area on the side of the torso. This region is located between the lower part of the chest and the upper part of the hips. Understanding the precise position of the flanks and the structures beneath them is important when discussing symptoms or medical procedures. This area is frequently referenced in clinical settings due to the organs it contains and its role in various health conditions.
Where Are the Flanks Located?
The flanks represent the side region of the trunk, situated on either side of the body. The upper boundary is defined by the lower margin of the rib cage, specifically the last (12th) rib. The region extends downward to the top of the hip bone, known as the iliac crest.
This area corresponds to the lateral portion of the lumbar region of the back. Although associated with the side of the torso, the flanks wrap slightly toward the back, covering the soft tissue and muscle layers above the waistline. The flanks contain muscle, connective tissue, and subcutaneous fat.
What Causes Pain in the Flank Region?
Pain localized to the flank region often indicates an issue with the underlying organs. The kidneys are positioned deep within this area, just beneath the rib cage toward the back, making them the most frequent source of discomfort. Severe, sharp pain known as renal colic is the classic presentation of kidney stones (urinary calculi). This intense pain occurs when a stone obstructs the urinary system’s drainage.
Another significant cause of pain is pyelonephritis, which is an infection of the kidney. This condition often develops from an untreated urinary tract infection and may be accompanied by fever, chills, or painful urination. The flank region is also susceptible to musculoskeletal issues, such as strains or sprains in the large muscles of the back and side. Furthermore, degenerative conditions of the spine, like arthritis or a herniated disc, can cause nerve irritation that radiates pain into the flank area.
The Flanks in Medical Procedures
The flank region holds importance in diagnostic evaluation and surgical planning. During a physical examination, doctors assess the flanks for tenderness, often focusing on the Costovertebral Angle (CVA) over the kidneys. Tenderness in this location can indicate inflammation or infection within the kidney.
Diagnostic imaging relies on the flank area to visualize internal structures. Ultrasound and computed tomography (CT) scans are routinely performed through this region to assess the size, structure, and function of the kidneys and ureters. The flanks also serve as a traditional point of surgical access for kidney procedures. Surgical approaches, such as removing a kidney (nephrectomy) or accessing stones, utilize an incision in the flank area to provide a direct path to the deep organ.