Trunk anatomy
The complexity of human trunk anatomy is primarily related to the functional considerations of each specific area contained within this region. The trunk is the largest part of the body and makes up 35%–40% of total body surface area. Perhaps more importantly, the cavitary contents lying below the skin, muscle, and bones of the trunk are critical to survival. Thorough understanding of this complex anatomy is required to manage wounds related to surgery, cancer, infection, trauma, or congenital anomalies. Additionally, there are a variety of aesthetic procedures which alter the form of the trunk, and understanding the anatomy of these areas is essential for safety and success. For the purposes of this chapter, the trunk will be divided into the following regions: anterior chest, abdomen and flank, back, perineum, and buttock. These regions may help the reconstructive surgeon to organize their approach to defect assessment and the various reconstructive options. With this in mind, each topic will be discussed by highlighting the pertinent muscles, bones, vascular structures, and nerves contained within that location. Prior to focusing on a specific region, it is important to understand the general surface anatomy of the trunk as well as the pattern of small vessel distribution, known as angiosomes.
