Flank is area between anterior and posterior axillary lines. Due to retroperitoneal region, delay in injury to duodenal, rectal, pancreatic and vascular structures can delay septic and hemorrhagic shock.
CT is imaging of choice. Consider doing rectal exam to look for blood in rectum. If peritonitis signs, IV antibiotic and surgical consult.
Exploratory laparotomy for GSW to flank usually. Stabs to flank are treated conservatively. Local wound exploration is less accurate in this region.
Penetrating Buttock Trauma
Usually GSW due to large musculature area. Stabs rare. 30% of buttock GSW need surgery. Can injure lower GU, GI, sometimes vascular.
Check neuro exam. Can hit femoral or sciatic nerve. Rare to hit plexus.
Cystourethrogram if blood in UA with wound close to GU system. Sometimes may need proctosigmoidoscopy if concern for colonic blood with rectal exam.
Tintinalli, Seventh Edition, Chapter 261: Penetrating Trauma to the Flank and Buttock
Rosens, Chapter 39: Abdominal Trauma