Redefining Fasciocutaneous Microanatomy: An Illustrated Review of Current Concepts and Their Clinical Correlates

Emerging anatomical concepts challenge microsurgical dogma. The current anatomy of the skin and subcutaneous tissue was reviewed with the objective of challenging the existing understanding of fasciocutaneous microanatomy using an updated anatomical model. Numerical anatomical data were compiled and utilized to create an updated and scaled model, defining integumentary neuroarterial, venolymphatic, and connective tis - sue systems. Additionally, a second model detailing the neurovasculature of the head and neck is presented, illustrating the relations of perforator arteries. Microangiosomes, the strength of their connections, and their relation to dissection planes are described. Clinically relevant structures are outlined, along with general principles and regional variations. We explore the viability of dermal plexus flaps and their potential for engraftment through plexus-to-plexus apposition. A comparison is drawn between subdermal and deep-dermal plexi. Furthermore, the peculiarities of head and neck perfusion and lymphatic drainage are discussed. These models inform our approach to dissection planes, fluid injection depths, flap via - bility, neurotization, post-inflammatory hyperpigmentation, tissue engraftment, debulking, and head and neck lymphatic drainage. This illustrated review offers an updated understanding of fasciocutaneous microanatomy and how to safely utilize it.