Two new cutaneous free flaps: the medial and lateral thigh flaps

Two new cutaneous free-flap donor areas are described on the medial and lateral sides of the thigh. The medial thigh flap is supplied by an unnamed artery from the superficial femoral artery and is drained by the accompanying venae comitantes. Its nerve supply is from the medial femoral cutaneous nerve. The lateral thigh flap has its vascular pedicle from the third perforating artery of the profunda femoral artery and its accompanying vein. The lateral femoral cutaneous nerve provides sensation over the area. These flaps provide a large surface area of both skin and subcutaneous tissue without the usual bulk of subcutaneous fat and muscle. Their desirable features include long vascular pedicles with large vessel diameters and potential of being neurovascular flaps with specific sensory nerve supply and predictable anatomy. The principal disadvantage is that the donor site may leave a slight contour defect with primary closure or require grafting when a large flap is taken. We predict that these flaps will become important donor sites for reconstructive problems requiring resurfacing of cutaneous defects in various anatomic areas.     

Anatomic study of the venous drainage architecture of the forearm skin and subcutaneous tissue

The venous anatomy of the forearm skin was examined radiographically in 15 fresh cadavers that had been injected systemically with a lead oxide-gelatin mixture. In 10 specimens, the forearm skin was divided into the skin and superficial adipofascial layer and the deep adipofascial layer. Five specimens were radiographed stereoscopically. Despite the thinness of the skin and subcutaneous tissue of the forearm, the cutaneous vein was seen three-dimensionally. Judging from the architecture and direction of the venous valves, most of the venous blood that had perfused the dermis was believed to: (1) pool in a venous network located in the superficial zone of the skin and subcutaneous tissue, (2) flow chiefly in the accessory cephalic and median antebrachial veins, and (3) enter the cephalic and basilic veins near the antecubital fossa. Venae comitantes of the septocutaneous and musculocutaneous perforators of the radial or ulnar arteries were thought to be only bypasses to the deep vein.     

Hematolymphatic transport in skin, subcutaneous tissue and superficial lamina of the fascia of the lower leg in varicose veins]

The lymphatic bed of the skin and subcutaneous tissues of the lower leg from 20 operated patients was studied by light and electron microscopy and by phlebographic methods. Three stages of development of the disease were examined: without complicated form of varicose veins, complicated form, and postthrombophlebitic syndrome. Morphological features of the state of the lymphatic bed of the skin, subcutaneous connective tissue and fascia of the lower leg in the initial stage of disease show the fine structure changes of lymphatic vessels and capillary walls interpreted as a compensation phenomenon. It seems that the structure alterations of endotheliocytes of lymphatic capillaries and the connective tissue surrounding them found in this study in the complicated form of the disease and the postthrombophlebitic syndrome are the basis of the mechanism of transport-resorption insufficiency of the lymph vessels' terminal flow paths.     

An anatomic study of the septocutaneous vessels of the leg

The vascular anatomy of the skin and fascia of the leg were studied in 20 cadaver legs that were injected and dissected under magnification to identify the origin, course, and distribution of vessels from the subfascial level to the skin. In addition to the longitudinally oriented fasciocutaneous arteries and the musculocutaneous perforators, the study demonstrated a third and important system of blood supply: the septocutaneous vessels. These vessels arise directly from the posterior tibial, anterior tibial, and peroneal arteries, run along the intermuscular septum, pierce the crural fascia, and ramify radially in the subcutaneous tissue superficial to the fascia. Longitudinally oriented anastomotic arcades are formed along the leg between branches of adjacent septocutaneous vessels. Each septocutaneous vessel has one or two venae comitantes. Selected methylene blue injections of the septocutaneous vessels revealed rich staining of the superficial surface of the fascia, the subcutaneous tissue, and distinct longitudinally oriented skin territories. There was no injection of dye in the deep surface of the fascia. It is felt that the septocutaneous vessels constitute an important source of skin circulation in the leg and form the basis for various fasciocutaneous flaps that have useful clinical applications.     

The relationship of the superficial and deep facial fascias: relevance to rhytidectomy and aging.

Controversy persists regarding the relationship of the superficial facial fascia (SMAS) to the mimetic muscles, deep facial fascia, and underlying facial nerve branches. Using fresh cadaver dissection, and supplemented by several hundred intraoperative dissections, we studied facial soft-tissue anatomy. The facial soft-tissue architecture can be described as being arranged in a series of concentric layers: skin, subcutaneous fat, superficial fascia, mimetic muscle, deep facial fascia (parotidomasseteric fascia), and the plane containing the facial nerve, parotid duct, and buccal fat pad. The anatomic relationships existing within the facial soft-tissue layers are (1) the superficial facial fascia invests the superficially situated mimetic muscles (platysma, orbicularis oculi, and zygomaticus major and minor); (2) the deep facial fascia represents a continuation of the deep cervical fascia cephalad into the face, the importance of which lies in the fact that the facial nerve branches within the cheek lie deep to this deep fascial layer; and (3) two types of relationships exist between the superficial and deep facial fascias: In some regions of the face, these fascial planes are separated by an areolar plane, and in other regions of the face, the superficial and deep fascia are intimately adherent to one another through a series of dense fibrous attachments. The layers of the facial soft tissue are supported in normal anatomic position by a series of retaining ligaments that run from deep, fixed facial structures to the overlying dermis. Two types of retaining ligaments are noted as defined by their origin, either from bone or from other fixed structures within the face.(ABSTRACT TRUNCATED AT 250 WORDS)     

Paravascular connective tissue structures of the veins of the pelvic cavity in man

The data on structure of the paravasal connective tissue formations in some parietal pelvic veins, in the utero-vaginal plexus veins, in the fatty tissue space veins of the rectum, of the vesicular and prostatic plexuses are presented, as well as those on connections between the fascial vaginae for the veins in the human subabdominal part of the pelvis and its fascial nodes. Theoretical interpretation of gaping of the pelvic fundal venous vessels is presented. Participation of the paravasal connective tissue formations in organization of the fascial nodes of the human small pelvis is stated.     

The reversed fasciosubcutaneous flap in the leg

A reversed fasciosubcutaneous tissue flap in the leg is described. This distally based flap is vascularized by the perforating cutaneous branches of the peroneal and tibialis posterior arteries. It must carry all its subcutaneous tissue. A study on the vascularization of the subcutaneous tissue reveals the predominance of the vascular network in this layer with regard to the dermal or fascial plane. The dermal vascular network at the donor site is sufficient to let the skin survive without its underlying subcutaneous vascular support. The flap can reach the malleolar and heel region. The advantages of this technique are (1) easy dissection, (2) preservation of the major vascular pedicles of the lower limb, (3) skin preservation at the donor site, thus preserving the shape of the limb, and (4) versatility (it is supple and can adapt to every surface, and it can be grafted on the deep or the superficial side). The addition of this technique to the armamentarium of the reconstructive surgeon has proved to be very useful in repairing soft-tissue defects in the lower limb. Often it can replace the classical fasciocutaneous flap or even a free flap.     

The dorsal thoracic fascia: anatomic significance with clinical applications in reconstructive microsurgery

The anatomic distribution and potential arterial flow patterns of the circumflex scapular artery were investigated by Microfil injection. These studies demonstrated that the circumflex scapular artery lies within the dorsal thoracic fascia, which plays a significant role in the circulation of the overlying skin and subcutaneous tissue. We conclude that scapular/parascapular flaps are fasciocutaneous flaps, the dorsal thoracic fascia can be transferred as a free flap without its overlying skin and subcutaneous tissue, and intercommunication exists between the myocutaneous perforators of the latissimus dorsi myocutaneous flap and the vascular plexus of the dorsal thoracic fascia. We present microvascular cases in which the vascular properties of the dorsal thoracic fascia facilitated wound closure with free fascia flaps or expanded cutaneous or myocutaneous flaps.     

The sensitivity of the nipple-areola complex: an anatomic study

Although preservation of the sensitivity of the nipple and areola is an important goal in breast surgery, only scant and contradictory information about the course and distribution of the supplying nerves is found in the literature. The existing controversy might be due to the difficulty in dissecting the thin nerves and to frequent anatomic variations that bias the results if only a small number of cadavers are dissected. We dissected 28 female cadavers and found that the nipple and areola were always innervated by the lateral and anterior cutaneous branches of the 3rd, 4th, and 5th intercostal nerves. The most constant innervation pattern was by the 4th lateral cutaneous branch (79 percent) and by the 3rd and 4th anterior cutaneous branches (57 percent). The anterior cutaneous branches took a superficial course within the subcutaneous tissue and terminated at the medial areolar border in all dissected breasts. The lateral cutaneous branches took a deep course within the pectoral fascia and reached the nipple from its posterior surface in 93 percent of the dissected breasts. In 7 percent of the dissected breasts, the lateral cutaneous branches took a superficial course within the subcutaneous fat and reached the nipple from the lateral side. These findings suggest that the nerves innervating the nipple and areola are best protected if resections at the base of the breast and skin incisions at the medial areolar border are avoided.     

Anatomical study of the venous drainage architecture of the scapular skin and subcutaneous tissue.

Venous anatomy of the skin and subcutaneous adipofascial tissue in the scapular region was examined in 14 specimens of 12 fresh cadavers that had been injected systemically with contrast medium. Three-dimensional analysis was performed by radiographing the specimens stereoscopically and splitting them into the skin and subcutaneous adipofascial tissue layers. From the architecture, most of the venous blood that had perfused the dermis was considered to pool in a polygonal venous network, located in the skin layer; to flow chiefly through some large communicating veins; and to enter the scapular, parascapular, or circumflex scapular veins. Most of the venous blood that had perfused the subcutaneous adipofascial tissue was considered to enter the scapular or parascapular veins directly.     

The fin musculature of cuttlefish and squid (Mollusca, Cephalopoda): morphology and mechanics

The lateral fins of cuttlefish and squid consist of a tightly packed three-dimensional array of musculature that lacks bony skeletal support or fluid-filled cavities for hydrostatic skeletal support. During swimming and manoeuvring, the fins are bent upward and downward in undulatory waves. The fin musculature is arranged in three mutually perpendicular planes. Transverse muscle bundles extend parallel to the fin surface from the base of the fin to the fin margin. Dorso-ventral muscle bundles extend from dorsal and ventral connective tissue fasciae to a median connective tissue fascia. A layer of longitudinal muscle bundles is situated adjacent to both the dorsal and ventral surface of the median fascia. The muscle fibres are obliquely striated and include a core of mitochondria. A zone of muscle fibres with a more extensive core of mitochondria is present in both the dorsal and the ventral transverse muscle bundles. It is hypothesized that these muscle masses include two fibre types with different aerobic capacity. A network of connective tissue fibres is present in the transverse and dorso-ventral muscle masses. These fibres, probably collagen, are oriented at 45 to the long axes of the transverse and dorsoventral muscle fibres in transverse planes.
A biomechanicayl analysis of the morphology suggests that support for fin movements is provided by simultaneous contractile activity of muscles of specific orientations in a manner similar to that proposed for other 'muscular-hydrostats'. The musculature therefore provides both the force and support for movement. Connective tissue fibres may aid in providing support and may also serve for elastic energy storage.     

A contribution to knowledge of the compartments and the fascial and septal formations of the popliteal fossa in the human fetus and the adult.

A contribution to knowledge of the compartments and the fascial and septal formations of the popliteal fossa in the human fetus and the adult. A study was made in human fetuses from the 3rd month onwards, newborn and the adult of the fascial and septal formations and the compartments of the popliteal fossa. Observations of serial sections of the knee of human fetuses, of macroscopic preparations of the knee of newborns and of ultrasound images of the popliteal fossa in adults showed that: the fascial formation covering the popliteal fossa consists of the popliteal fascia and the superficial fascia. The bud of the popliteal fascia is observable in the 3-month fetus as a layer of thin fibrillar connective tissue which is thicker in the tracts between the muscle buds. At birth the popliteal fascia is clearly a separate anatomical entity of continuous laminar structure which is thicker in the tracts between the muscles and thinner where it covers them. The superficial fascia becomes evident in fetuses at a later stage (6th month) in the form of a thin lamina in the frontal plane which at birth is well defined and observable as a thin continuous line deep below the subcutaneous layer. The septal formation consists of four septa: two in the sagittal plane (lateral and medial) and two in the frontal plane (lateral and medial). The bud of these septa appears in 4-month fetuses after the appearance of the popliteal fascia. They branch off from the thicker connective areas between the muscles buds as connective prolongations which later assume a laminar aspect and eventually become compact and form septa. In at-term fetuses and newborns these septal formations are clearly recognizable as antomical entities, which branch off from the deep surface of the thicker tracts of the popliteal fascia and are inserted into the femur. The relationships and connections with the muscular groups are also clearly visible. The organization and demarcation of the compartments, which is already delineated in the 6-month fetus, seems to be completed at birth, considering the presence of the superficial fascia, the popliteal fascia and the septa. It is possible to distinguish a superficial compartment between the popliteal and the superficial fascia an a deep compartment between the frontal septa, the skeletal plane and the popliteal fascia. This deep compartment is clearly subdivided by the two sagittal septa into three sectors (medial, intermediate and lateral). The medial and lateral sectors contain muscles, while the intermediate compartment contains the vasculonervous bundle and the popliteal adipose body.     

Venous drainage architecture of the temporal and parietal regions: anatomy of the superficial temporal artery and vein

Anatomy of the superficial temporal artery and vein was analyzed with arteriograms, venograms, and arteriovenograms of fresh cadavers that had been injected with contrast medium. The superficial temporal artery always divided into two major branches: the frontal and parietal branches. However, the superficial temporal vein divided into one, two, or three major branches. The distribution area of the major branches of the superficial temporal vein was larger than that of major branches of the superficial temporal artery, and arteriovenograms clearly demonstrated that, except for its proximal portion, the superficial temporal vein was independent of the superficial temporal artery. The frontal and parietal branches of the superficial temporal artery had thin venae comitantes that originated from the proximal portion of the superficial temporal vein, and the venae comitantes gave off branches toward the skin and the underlying soft tissue. Branches to the skin anastomosed with a superficial venous network in the skin layer, which was formed by ramifications of the superficial temporal vein. The venous architecture of the temporal and parietal regions consisted of cutaneous veins and venae comitantes and was basically similar to that of the forearm and scapular region.     

Cytological and functional characteristics of fascia adipocytes in rats: A unique population of adipocytes

The dermal adipocytes, superficial fascia and subcutaneous adipose tissue (SAT) exist in the interspaces between the dermis and muscular fascia. They are adjacent to each other and traditionally recognized as one SAT. Recently, the dermal adipocyte was redefined as a unique population independent from the SAT. Also, we identified a novel type of adipogenic progenitors in rat superficial fascia. This study aimed to examine cytological and functional characteristics of fascial adipocytes in rats. Superficial fascia had no adipocytes in neonatal rats but gradually appeared numbers of adipocytes in growing rats. Adipogenic progenitors were found to reside in fascia and had strong ability in spontaneous and induced adipogenic differentiation in vitro. Differentiated fascial adipocytes versus subcutaneous or visceral adipocytes expressed increased adipose triglyceride lipase but decreased beta-adrenoreceptor, perilipin-1 and hormone-sensitive lipase (HSL), thus having high basal lipolysis but low lipolysis response to catecholamines. Phosphorylation of perilipin-1 and HSL and translocation of HSL to lipid droplets were attenuated in response to catecholamines rather than post-adrenoreceptoral lipolytic stimulators. The results suggested that superficial fascia was an origin of adipocytes with distinct developmental, cytological and functional characteristics. We proposed that fascial adipocytes could be considered as a unique population of adipocytes in the body. The fascia origin of adipocytes as an adipogenic model might logically explain fat neogenesis occurred at anatomical locations where originally exist no adipose tissues and thereby no adipose-derived stromal precursors. Also, the special histoanatomical relations and overlaps between the dermis, superficial fascia, SAT, and their adipocytes were discussed.     

Glomerular bypass shunts in the kidney of the Atlantic hagfish,Myxine glutinosa

Summary The vascular pathways associated with the glomerulus of the Atlantic hagfish, Myxine glutinosa have been studied by scanning electron microscopy of corroded resin casts of the vasculature. Although the overall pattern of the renal vasculature did not differ from earlier reports, a previously unreported vascular pathway which arose from the renal artery and bypassed the glomerular capillaries in 28% of glomeruli was clearly demonstrated. Glomerular bypass shunts either ran to join the loose capillary network around Bowman's capsule and thereby drain into the network of vessels associated with the mesonephric duct (ureter), or ran directly into the ureteral system of vessels and subsequently into the posterior cardinal veins. Glomerular bypass shunts which theoretically permit renal arterial blood to bypass the process of filtration may play a role in the regulation of body fluid volume.     

Structure and histology of the wattle in the White bellbird (Procnias alba)

Structure and histology of the wattle in the male White bellbird ( Procnias alba ) are described. The proximal two-thirds of the wattle contains only very sparse, frail connective tissue and is isolated both from the respiratory tract and from pneumatic spaces in the skull. The wattle is richly vascularized, with an extensive network of veins, which completely fill the lumen in the distal third. The larger veins possess longitudinal as well as circular muscle. Longitudinal muscle bundles (some associated with feather follicles) are scattered in the loose connective tissue of the periphery. The wattle is compared in structure with the superficially similar frontal process of the turkey ( Meleagris gallopavo ). The mechanism of extension and retraction is discussed.     

Blood vascular architecture of the rat lingual papillae with special reference to their relations to the connective tissue papillae and surface structures: a light and scanning electron microscope study

Subepithelial blood vessels of the rat lingual papillae and their spatial relations to the connective tissue papillae and surface structures were demonstrated by light and scanning electron microscopy. In the rat, four types of papillae were distinguished on the dorsal surface of the tongue, i.e. the filiform, fungiform, foliate and circumvallate papillae. Vascular beds of various appearance were found in all four types of lingual papillae: a simple or twisted capillary loop in the filiform papilla; a basket- or petal-like network in the fungiform papilla; a ring-like network in the foliate papilla, and a conglomerated network surrounded by double heart-shaped capillary networks in the circumvallate papilla. These characteristic vascular beds corresponded to the shape of the connective tissue papillae and surface structures. The vascular bed beneath the gustatory epithelium in the fungiform, foliate and circumvallate papilla consisted of fine capillary networks next to the taste buds.