The Concepts of Propeller, Perforator, Keystone, and Other Local Flaps and Their Role in the Evolution of Reconstruction.

Learning objectives After studying this article, the participant should be able to: 1. Understand the history and physiology of perforator flaps. 2. Understand the concept of "free-style" perforator flaps and principles in design and harvest. 3. Understand the uses of perforator flaps in reconstruction and applications in new settings. 4. Understand new principles in single and multiple perforator flap harvest and adjunct techniques that can be used in perforator flaps. 5. Highlight pertinent anatomy and techniques for selected perforator flaps described. Summary Extended knowledge of vascular anatomy has propagated the development of perforator flaps, which preserve muscle function and reduce morbidity. This has been achieved through the exemplary works of Manchot, Salmon, Milton, Taylor, and many others. With over 350 clinically relevant perforators in the body, this has created new flap options and a sense of creative freedom for reconstruction tailored toward a specific defect, without constraints of specific landmarks and using a "free-style" approach. Dominant perforators may be found in zones of high perforator density or "hot spots," which can help to conceptualize local flap options and aid flap design. This article aims to outline the history, physiology, and principles of flap design and harvest, and highlight traditional and evolving concepts and modifications of contemporary and traditional flaps that are changing reconstructive practice. This is a broad overview focusing on clinical applications, highlighting key concepts in a selection of new or evolving flaps being used in clinical practice and providing source references to acquire detailed flap descriptions.