Superficial Fascial System (SFS) of the Trunk and Extremities

Abstract
Surgeons and anatomists have largely ingored the superficial fascia of the body. In fact, many anatomists have doubted the existence of this fascia as a distinct entity. The superficial fascia does exist and is functionally important. Understanding the anatomy and pathologic changes with age of the superficial fascial system (SFS) of the trunk and extremities may help explain body-contour deformities and provide the anatomic basis for surgical correction. The anatomy of the superficial fascial system was studied in 12 fresh and embalmed cadavers, cross-sectional cadaver segments, and 20 body-contour patients. The superficial fascial system is a connective-tissue network that extends from the subdermal plane to the underlying muscle fascia. It consists primarily of one to several thin, horizontal membranous sheets separated by varying amounts of fat with interconnecting vertical or oblique fibrous septae. Superficial fascial system anatomy varies with sex, adiposity, and body region. The topographic landmarks of the human body are largely the result of superficial fascial system anatomy (zones of adherence) and its relationships with fat and muscle fascia. The primary function of the superficial fascial system is to encase, support, and shape the fat of the trunk and extremities and to hold the skin onto the underlying tissues. With age and sun damage, the entire skin-superficial fat-superficial fascial system unit relaxes and stretches, resulting in ptotic soft tissues, pseudo-fat deposit deformity, and cellulite. There are two types of cellulite in women. Primary cellulite, or cellulite of adiposity, is due to hypertrophied superficial fat cells and is not amenable to surgical treatment. Secondary cellulite, or cellulite of laxity, results from laxity of the skin and soft tissues as a result of age, sun damage, or massive weight loss, or after liposuction. Secondary cellulite is surgically correctable by lifting techniques. Superficial fascial system suspension is an important adjunct to body-contour surgery of the trunk and extremities. Similar to the SMAS role in rhytidoplasty, repair of the superficial fascial system diffuses the tension on the skin flap, more effectively lifts areas of soft-tissue ptosis, and provides longer-lasting support. In addition, the superficial fascial system suspension allows more normal contours in both static and dynamic activities. The superficial fascial system repair has been used to enhance the following body-contour procedures: abdominoplasty, thigh-buttock lift, back-flank lift, medial thigh lift, infra-mammary fold reconstruction, and augmentation mammaplasty.