26/03/2015 WHAT IS THE SUPERFICIAL FASCIA? The Anatomical Terminology [FCAT] suggested that the term fascia could be used to indicate a sheath, sheet or other dissectible ANATOMY OF connective tissue aggregations. THE FASCIAL SYSTEM The aim of our studies is to demonstrate the constant presence of a sheet of connective tissue inside the subcutaneous tissue. Skin Antonio Stecco M.D. Sup. F Department of Human Anatomy and Physiology, University of Padova, Italy Deep F Fazzari Foot: dorsal region (azan-Mallory, 25x)2 THE SUPERFICIAL FASCIA OF THE ABDOMEN Computer axial tomography scan superficial fascia S.fascia Retinacula cutis A fibrous sheet, corresponding to the Scarpa’s fascia, could be easily isolated inside the subcutaneous adipose tissue. L2 superficial fascia 1 26/03/2015 The superficial fascia of the back Superficial fascia In the dorsum, the superficial fascia appears At MRI in T1 weight imaging the as a thick fibrous lamina superficial fascia is easy to see both extending in a in coronal and in sagital planes. homogenous manner from the neck to the gluteal region, easily separable from the deep fascia. It adheres to the deeper layers along the superficial fascia spinous processes and along the inferior margin of the scapula. 5 The SUPERFICIAL FASCIA IN THE THORACIC REGION The superficial fascia of the LIMBS (Stecco et al, JBMT, 2009) Platysma muscle The SF envelops the platysma muscle and it is easily separable from the deep 8 Pectoralis major muscle fascia, except at the level of the 6 ° rib. The SF of the thigh The SF of the leg The SF of the arm 2 26/03/2015 The SUPERFICIAL FASCIA of the extremities WHAT IS THE SUPERFICIAL FASCIA? The superficial fascia could be epidermidis recognized in almost all the dermadermis human body, even if with regional specialization. superficial adipose layer and retinaculum cutis superficialis Vertical/oblique septa connect layers of fibroelastic tis. superficial fascia the superficial fascia to the deep adipose layer skin (retinaculum cutis and retinaculum superficialis or skin ligaments) cutis profondus and the deep fascia deep fascia (retinaculum cutis profundus) muscle forming a 3-D network between the fat lobules. The superficial fascia adheres to the deep fascia and it is also connected with the skin by thick vertical septa. 9 REGIONAL SPECIALIZATIONS IN THE The appearance of the SMAS in CT FACE (Stecco et al, Italian J of Anatomy, 2008) • In the face, we can recognize three different patterns. • Changes in the quantitative and qualitative characteristics of the retinacula cutis and superficial fascia of the face, may contribute to ptosis of facial soft tissues In axial CT images, the SMAS appears as a relatively hyperdense during aging. tortuous line between the hypodense superficial adipose tissue 11 Stecco et al (2009) Histotopographic study of the fibroadipose connective cheek system. CTO (SAT) and the hypodense deep adipose tissue (DAT). 3 26/03/2015 Histological features SUPERFICIAL FASCIA AND MUSCLES of the SUPERFICIAL FASCIA In humans, muscular fibers can be found Superficial fascia of the thigh inside the superficial fascia, particularly in (azan-Mallory, 25x) the neck (platysma muscle), in the face (SMAS), in the anal region (external anal sphincter), in the scrotum (dartos). The superficial fascia is homologous to the cutaneous muscle layer (panniculus carnosus) found in other mammals. Superficial fascia of the leg (immunohistochemical stain anti-S100 antibody, 100x) Superficial fascia in the temporal region (van Gieson stain, 100x) 14 Resistance to traction in different directions Resistance to traction in different directions In the dorsum, the superficial fascia shows a great variation in its behaviour, going from a maximum of Mean value of resistance to traction: 10 Kg to a minimum of 0.5 Kg. SF of the dorsum: 8.5 Kg SF of the abdomen: 2.8 Kg SF of the leg: 1.7 Kg RESISTANCE (Kg) RESISTANCE (Kg) 12 7 10 6 5 8 4 6 3 Mean value of resistance to traction: 4 2 SF of the dorsum: 6 Kg 2 1 SF of the abdomen: 5.5 Kg 0 0 SF of the leg: 1.4 Kg T1 T3 T5 T7 T9 T11 L1 L3 L5 T1 T3 T5 T7 T9 T11 L1 L3 L5 4 26/03/2015 THE SUPERFICIAL FASCIA AND VESSELS Plastinated section, saphenous v. In some regions the superficial fascia splits, forming special compartments around major subcutaneous veins and lymphatic vessels. In this way it protects the vessels during movements and maintains the vessels open. 17 The superficial fascia and the vessels SUPERFICIAL Fascia AND NERVES Perforantes vessel crossing the SF Vascular plexus inside the fascia Inside the superficial fascia we can recognize the superficial vascular plexus and numerous lymphatic ducts. Also the perforantes vessels The terminal fibers of the nerves inside have to cross the superficial the superficial fascia: could be this a fascia to reach the skin. The lymphatic ducts are inside the SF19 Superficial peroneal nerve possible site of compression? 20 5 26/03/2015 The POSSIBLE ROLES OF THE superficial fascia Normal morphology of Hypodermis The features of the SF and its relationships with the surrounding It is an external tissues determine: stimulation. • The mobility of skin with respect to the deep planes (age ptosis and wrinkles, plastic surgery) • Protection of the superficial vessels and nerves (varicose SKIN SKIN veins, tired feeling and weakness in the legs…) SKIN • Lymphatic drainage (lymphoedema, fascitis, cellulitis…) SUPERFICIALSUPERFICIALSUPERFICIAL FASCIA FASCIA FASCIA • The separation between esteroception (skin) and DEEP FASCIA proprioception (deep fascia) DEEPDEEP FASCIA FASCIA Pathological morphology of Hypodermis Is it external or internal stimulation ? SKIN SKIN Retinacula cutis profundus SUPERFICIALSUPERFICIAL FASCIA FASCIA Superficial fascia Retinacula cutis “Densification” of the connective DEEPDEEP FASCIA FASCIA tissue (retinacula cutis). superficialis 6 26/03/2015 The retinacula cutis Superficial fascia is more adherent to the skin ► The retinacula cutis provide an anchorage of skin to underlying SKIN tissues and of the superficial fascia to the deep fascia. ► In this way a flexible and yet resistant mechanism of FatFatlobules transmission of the mechanical loads from multidirectional SUPERFICIAL FASCIA forces could be recognized. ► Regional specializations determine the variations in mobility of the skin with respect to underlying tissues. DEEP FASCIA SKIN The septa of the retinaculum cutis superficialis are usually many and SKIN SKIN vertically oriented, while the septa of the retinaculum cutis profondum are SUPERFICIAL FASCIA SUPERFICIAL FASCIA SUPERFICIAL FASCIA less, thinner and with an oblique direction. In this way the superficial fascia DEEP FASCIA DEEP FASCIA DEEP FASCIA is generally more adherent to the skin than to the deep fascia. GROSS ANATOMY: the fasciae of the thigh GROSS ANATOMY: the fasciae of the leg Subcutaneous adipose tissue Isolation of the Deep fascia of the thigh and Superficial fascia Deep fascia Deep and epimysial fasciae after having removed the skin superficial fascia epimysium of the quadriceps 7 26/03/2015 GROSS ANATOMY: fasciae of the upper limb MORPHOMETRIC ANALYSIS: the deep fasciae of the limbs The deep fascia is easily separable from the epimisyum of the underlying muscles It shows aponeurotic features and it is very resistant to traction. It presents different thicknesses according to the evaluated zones. Subcutaneous tissue of the Deep fascia of the posterior Deep and epimysial fascia of forearm region of the forearm the biceps brachii muscle HISTOLOGICAL STUDY: the deep fasciae of the limbs HISTOLOGICAL STUDY: the deep fasciae of the limbs Multiple layers of undulated In the muscular fascia of the collagen fibre bundles form the upper limb , few elastin fibers deep fascia. In each layer the bundles are are also present. They form an parallel to each other. irregular mesh. In the deep fascia of the inferior limb , we found very few A thin layer of loose connective elastin fibers. tissue separates the different layers. Adjacent layers of collagen fibers show different orientations . 8 26/03/2015 3D RECONSTRUCTION of the collagen fibers 3D RECONSTRUCTION of the elastic fibers 78° The collagen fibers are disposed parallel to each other to form 2/3 layers (277.6 µm). In adjacent layers, the bundles show different orientations, creating an angle of 78 °. The collagen volume fraction is about 18%. 3 2,5 2 1,5 1 0,5 % of % elastic fibres 0 0 depth 40 80 120 160 200 240 280 320 360 440 480 520 560 600 640 680 720 760 800 840 880 920 960 1000 Only a few, short elastic fibres are present, forming an irregular mesh. Their volume is less than 1%. Their concentration increases descending to the deeper layers. THE DEEP FASCIAE: from an irregular fibrous The multilayer structure of tissue to a multilayer organization (Stecco et al, 2008) the deep fasciae of the limbs Layer I ϕ I Serial sections of fascia ϕ II multi-layered tissue Layer II Medial region of the elbow Thanksa to the different orientationsb of the collagec n fibers in The presence of loose connective tissue interposed between the layers, the fascia has strong resistance to traction even adjacent layers permits local sliding, and so from a mechanical when it is exercised in different directions. point of view the single layers could be considered independently. 9 26/03/2015 The loose connective tissue permits the different layers to slide one on the other SLIDING SYSTEM Presence of HA in the connective tissue “Hyaluronan is ubiquitously distributed in the extracellular space of higher animals; the highest concentrations are found in soft connective tissues” TC Laurent and JR Fraser; Hyaluronan; The FASEB Journal, 1992 Vol 6, 2397-404, 10 26/03/2015 Presence of HA in Presence of HA under the connective deep fascia tissue “Hyaluronic acid is localized to the deep or muscular surface (arrow) of the deep fascia” McCombe D et al; The “HA is present in most histochemical structure of the deep fascia and its connective tissues and structural response to surgery; J Hand Surg Br.