Erich Brenner

Clinical anatomy of the pelvic floor.

The study presented here comparing cross-sectional anatomy of the fetal and the adult pelvic connective tissue with the results of modern imaging techniques and actual surgical techniques shows that the classical concepts concerning the subdivision of the pelvic connective tissue and muscles need to be revised. According to clinical requirements, the subdivision of the pelvic cavity into anterior, posterior, and middle compartments is feasible. Predominating connecting tissue structures within the different compartments are: Paravisceral fat pad within the anterior compartment (Fig. 17, I), rectal adventitia or perirectal tissue within the posterior compartment (Fig. 17, II), and uterosacral ligaments within the middle compartment. The nerve-vessel guiding plate can be found in all of these compartments; it starts within the posterior compartment and it ends within the anterior one. It constitutes the morphological border between the anterior and posterior compartments in the male. This border is supplied by the uterosacral ligaments in the female. Whereas in gross anatomy no further border is discernable between anterior and posterior or middle compartment, the rectal fascia (hardly visible in embalmed cadavers) demarcates the rectal adventitia and is one of the most important pelvic structures for the surgeon. In principle, the outlined subdivision of the pelvic connective tissue is identical in the male and in the female; facts that become clear from early human life and that are already established during this period (Fig. 18). The uterus is interposed between the bladder and rectum and subdivides the pelvic peritoneum into two pouches thus establishing the only real difference between male and female pelvic cavity. The preferential direction of the pelvic connective tissue fibers is not changed by the interposition of the uterovaginal complex. The pelvic floor muscles are composed of the portions of the levator ani muscle, the muscles of the cavernous organs and the deep transverse perineal muscle in the male. The latter does not exist in the female. We have clearly shown that the different muscles can already be found in early human life and that they are never intermingled with the muscular walls of the pelvic organs. The levator ani muscle of the female, however, is intermingled with connective tissue long before the female sexual hormones exert influence. We have also shown that the distinct sexual differences within the pelvic floor muscles as well as within the sphincter muscles can already be found in early human life. Both the external urethral and the external anal sphincter muscles are not completely circular. The external anal sphincter is intimately connected with the internal sphincter as well as with the longitudinal muscle. Whereas the innervation and function of the urethral sphincter muscles are mostly clear, cloacal development, innervation, and function of all parts of anal sphincter complex are not completely clarified. As to the support of the pelvic viscera, we believe that intact pelvic floor muscles, an undisturbed topography of the pelvic organs, and an undisturbed perineum are of more importance than the so-called pelvic ligaments. Our hypothesis points to the fact that the support of pelvic viscera is multistructural. Thus in pelvic surgery, a lot of techniques have to be revised with the aim to preserve or to reconstruct all the structures mentioned. This is a multidisciplinary task that can only be solved by cooperation of morphologists, urologists, gynecologists, and coloproctologic surgeons or by creating a multidisciplinary pelvic floor specialist.

Anal sphincter complex: reinterpreted morphology and its clinical relevance.

AbstractPURPOSE: Recent clinical studies on the anal sphincter complex have criticized the lack of reliable morphologic concepts. The purpose of this study was to determine the anatomy and histology of the anal sphincter complex with the help of undisturbed anatomic preparations. METHODS: The anal sphincter complex was studied in axial, sagittal, and coronal sections of human fetal, newborn, and adult pelves. RESULTS: The anal canal was surrounded by the internal sphincter, the longitudinal muscle layer, and an external sphincter that turned in to become continuous with the internal sphincter and with it to enclose the longitudinal muscle bundles. The classical tripartite subdivision of the external sphincter was not confirmed. The external sphincter seems not to be a complete circle in certain planes, neither in the male nor in the female. Sexual differences of the ventral part of the external sphincter were already present in fetuses. Large lamellated corpuscles were embedded within the interlacing smooth and striated muscles. Branches of the pudendal nerve innervated them. CONCLUSION: Our anatomic and histologic findings highly correlate with the results of magnetic resonance imaging and endosonography as well as with the physiologic findings. Furthermore, they are of great clinical importance for the understanding of sphincter defects during vaginal delivery and for anorectal operations in the adult as well as in the child.

New, simple, ultrasound-guided infiltration of the pudendal nerve

PURPOSE: We report the topographic relationship of the pudendal nerve to the accompanying pudendal vessels and the ischial spine and provide the basics for an ultrasonographic depiction of these structures. METHODS: Twenty‐nine female and 29 male adult human cadavers were positioned prone to expose the deep gluteal region. In 58 left and 58 right pelves the course of the pudendal nerve and vessels at the ischial spine were evaluated and analyzed statistically (n=116). RESULTS: Multitrunked pudendal nerves were found in 40.5 percent with a left‐ vs. ‐right ratio of 1:1.5. The diameters of the single‐trunked nerves ranged from 1.3 to 6.8 (mean 3.6±1.1) mm. In 75.9 percent the pudendal nerve was found medial to the accompanying internal pudendal artery. The distance to the artery ranged from 17.2 mm medial to 8 mm lateral (mean, 3.4 mm medial±4.1 mm). The distance to the tip of the ischial spine mm from 13.4 mm medial to 7.4 mm lateral (mean, 2.1 mm medial±3.7 mm). CONCLUSIONS: The knowledge of the close spatial relationship between the pudendal nerve and the internal pudendal artery is important for any infiltration technique and even surgical release. It demands real‐time, visually controlled infiltration techniques, such as with ultrasound.PURPOSE: We report the topographic relationship of the pudendal nerve to the accompanying pudendal vessels and the ischial spine and provide the basics for an ultrasonographic depiction of these structures. METHODS: Twenty-nine female and 29 male adult human cadavers were positioned prone to expose the deep gluteal region. In 58 left and 58 right pelves the course of the pudendal nerve and vessels at the ischial spine were evaluated and analyzed statistically (n=116). RESULTS: Multitrunked pudendal nerves were found in 40.5 percent with a left-vs.-right ratio of 1:1.5. The diameters of the single-trunked nerves ranged from 1.3 to 6.8 (mean 3.6±1.1) mm. In 75.9 percent the pudendal nerve was found medial to the accompanying internal pudendal artery. The distance to the artery ranged from 17.2 mm medial to 8 mm lateral (mean, 3.4 mm medial±4.1 mm). The distance to the tip of the ischial spine mm from 13.4 mm medial to 7.4 mm lateral (mean, 2.1 mm medial±3.7 mm). CONCLUSIONS: The knowledge of the close spatial relationship between the pudendal nerve and the internal pudendal artery is important for any infiltration technique and even surgical release. It demands real-time, visually controlled infiltration techniques, such as with ultrasound.

Human body preservation – old and new techniques

This review deals with the art of (anatomical) embalming. The first part contains a brief historical review of the history of embalming, starting with ancient cultures such as the Egyptians and the lesser known Chinchorro culture, then going down the centuries and describing the anatomical techniques developed over the last two centuries. The second part deals in detail with the chemicals used for embalming purposes. The third part deals with several approaches to evaluating embalming methods, their suitability for biomechanical testing, antimicrobial properties, histological appearance, and usability. The fourth and final part analyze the European Biocidal Products Directive (98/8/EC) in the light of embalming.

The anterolateral ligament of the knee: A dissection study

BACKGROUND Recent studies have described the presence of the anterolateral ligament (ALL). However, there is still no consensus regarding the anatomy of this structure with the topic controversially discussed. The aim of this study was to provide an anatomical description of the ligamentous structures on the anterolateral side of the knee with special emphasis on the ALL. METHODS Forty-four human cadaveric knees were dissected to reveal the ALL and other significant structures in the anterolateral compartment of the knee joint. The ALL was defined as a firm structure running in an oblique direction from the lateral femoral epicondyle to a bony insertion at the anterolateral tibia. RESULTS The ALL was identified in 45.5% (n=20) of the dissected knee joints. The structure originates together with the fibular collateral ligament (45%) or just posterior and proximal to it (55%). The ligament has an extra-capsular, anteroinferior, oblique course to the anterolateral tibia with a bony insertion between Gerdys tubercle and the fibular head. The ALL had its greatest extend at 60° of knee flexion and maximal internal rotation. CONCLUSION The ALL is a firm ligamentous structure in the anterolateral part of the knee present in 45.5% of the cases. Given the course and characteristics of this structure, a function in providing rotational stability by preventing internal rotation of the knee is likely. CLINICAL RELEVANCE The ALL might be an important stabilizer in the knee and may play a significant role in preventing excessive internal tibial rotation and subluxation of the knee joint.

Vascular anatomy of the supraclavicular area revisited: feasibility of the free supraclavicular perforator flap.

Background: The supraclavicular skin has been studied extensively and used as a pedicled flap for face and neck reconstruction. Its use as a free flap has not paralleled its use as a pedicled flap. The authors performed an anatomical investigation to assess the possibility of harvesting a free supraclavicular flap with the donor-site scar lying in the supraclavicular crease. In this article, the authors present the results of their anatomical study together with the preliminary clinical applications. Methods: Skin vascularization and feasibility of a free supraclavicular perforator flap were studied on 25 cadavers (15 fresh cadavers injected with colored latex at the Universiteé René Descartes in Paris; and 10 formalin-fixed, noninjected cadavers at the Innsbruck Medical University). The flap was used in two patients at the Plastic Surgery Department of the University of Palermo for a cutaneous facial reconstruction and intraoral reconstruction after cancer excision. Results: An average of four perforators were consistently found in the supraclavicular area coming from the transverse cervical artery. Venous perforators drain into the superficial venous plexus rather than into the venae comitantes of the transverse cervical artery. Two flaps were successfully used based on these vessels. Conclusions: The vascularization of the supraclavicular skin depends on skin perforators coming from the transverse cervical artery and draining into the superficial venous plexus. Based on these vessels, a reliable free supraclavicular flap seems to be safe to harvest, with the scar hidden in the supraclavicular crease. The preliminary clinical applications of such a flap gave promising results, suggesting its potential applications.

Anatomic study on the transverse cervical vessels perforators in the lateral triangle of the neck and harvest of a new flap: the free supraclavicular transverse cervical artery perforator flap

BackgroundVessels in the supraclavicular area and their contribution to skin vascularization have always been studied for flaps planning in head and neck reconstruction and many pedicled flaps have been described based on those vessels. Little has been written instead about the vascularization of the supraclavicular skin itself for the use as a free flap. The purpose of this anatomical study was to assess the vascularization of the supraclavicular skin and the possibility of finding an adequate pedicle to harvest it as a free flap in order to close the donor site directly.MethodsA total of 25 cadavers, 10 formalin fixed and 15 fresh, have been studied in cooperation with the Division for Clinical–Functional Anatomy, Department of Anatomy, Histology and Embryology, Innsbruck Medical University, Innsbruck, Austria and the Laboratoire d’Anatomie, Universiteé R. Descartes, Paris, France.ResultsThe supraclavicular skin was nourished by perforators coming from the transverse cervical artery and constantly present in an average number of four. Venous drainage was accomplished through the superficial cervical vein, and not through the venae comitantes of the transverse cervical artery.ConclusionsBased on the results of this investigation, a free supraclavicular transverse cervical artery perforator (STCAP) flap seems to be feasible pedicled on perforators from the transverse cervical artery and drained by the superficial cervical vein. Due to its thickness and skin texture, it can be indicated for facial and intraoral defects, with the limitations of a relatively short pedicle. Primary closure of the donor site can be accomplished concealing the scar in the neck crease.

Ossification in the human calcaneus: a model for spatial bone development and ossification

Perichondral bone, the circumferential grooves of Ranvier and cartilage canals are features of endochondral bone development. Cartilage canals containing connective tissue and blood vessels are found in the epiphysis of long bones and in cartilaginous anlagen of small and irregular bones. The pattern of cartilage canals seems to be integral to bone development and ossification. The canals may be concerned with the nourishment of large masses of cartilage, but neither their role in the formation of ossification centres nor their interaction with the circumferential grooves of Ranvier has been established. The relationships between cartilage canals, perichondral bone and the ossification centre were studied in the calcaneus of 9 to 38‐wk‐old human fetuses, by use of epoxy resin embedding, three‐dimensional computer reconstructions and immunhistochemistry on paraffin sections. We found that cartilage canals are regularly arranged in shells surrounding the ossification centre. Whereas most of the shell canals might be involved in the nourishment of the cartilage, the inner shell is directly connected with the perichondral ossification groove of Ranvier and with large vessels from outside. In this way the inner shell canal imports extracellular matrix, cells and vessels into the cartilage. With the so‐called communicating canals it is also connected to the endochondral ossification centre to which it delivers extracellular matrix, cells and vessels. The communicating canals can be considered as inverted ‘internal’ ossification grooves. They seem to be responsible for both build up intramembranous osteoid and for the direction of growth and thereby for orientation of the ossication centre.

Fetal development of the first metatarsophalangeal joint complex with special reference to the intersesamoidal ridge.

In most individuals, plantar to the first metatarsal head, a more or less well developed crest separates the two furrows for the medial and the lateral sesamoid bones. In some instances, the absence of this crest has been observed in a previous study. This observation may be related to a pathological and/or an ontogenetic development. For the present examination, we have assumed the ontogenetic hypothesis. Twenty-two feet were examined at different developmental stages from week 12 to 38. The feet were prepared for examination using methods of plastination-histology. Sesamoids have already developed from the joint capsule by the first stage (12th week). Attachment bundles of collagenous fibers have deeply penetrated the cartilage of the sesamoids on their capsular side. Only some inner fibers of the muscular tendons join the sesamoids on their plantar side. The intersesamoid ligament is blended into the synovial tendon sheath of the flexor hallucis longus. The plantar crest has already developed in the fetal cartilage of the first metatarsal head as a strong ridge. With further growth, the surfaces become inwardly tapered on both sides of the ridge through the sesamoid bones, so that in the end the ridge results in a more or less clear crest. If the tapering of the furrows for the sesamoid bones proceeds too briskly or too far, this can result in an absence of the plantar crest. If the absence of this crest stands in relation to the formation of a Hallux valgus, this result would be a first indication of an developmentally based cause for this wide-spread disease of the foot.

Segmental anatomy of the vastus lateralis: Guidelines for muscle-sparing flap harvest

Background: The vastus lateralis muscle is a versatile donor site for pedicled and free flaps that, despite great potential, remains unpopular. Although the muscle is classically described as a single belly, evidence exists for a more complex morphology. The aim of this study was to investigate the segmental anatomy of the vastus lateralis muscle and the feasibility of selective flap harvest. Methods: Ten cadaveric lower limbs were investigated. Muscular partitions were identified according to morphologic architecture, vascular supply, and nerve supply; guidelines for selective flap harvest were described. Twenty-three segmental vastus lateralis (n = 14) or chimeric anterolateral thigh–vastus lateralis flaps (n = 9) were raised based on neurovascular segmental supply, and used as noninnervated free flaps for reconstruction of moderate and large defects of the head and neck, trunk, or lower limbs. Intraoperative electrostimulation was used to confirm segmental innervation. Lower limb function was evaluated through the Lower Extremity Functional Scale. Results: The authors clearly identified three anatomical partitions, which receive a constant segmental neurovascular supply, and two aponeuroses. The authors successfully applied the proposed guidelines for flap harvesting to all 23 patients. Intraoperative electrostimulation confirmed functional integrity of both the flap and the spared partitions. All muscle flaps survived. Donor-site morbidity was negligible, with comparable mean preoperative and postoperative Lower Extremity Functional Scale values (67.7 versus 67.4; p > 0.05). Conclusions: This study provides detailed knowledge on the morphologic and neurovascular anatomy of the vastus lateralis muscle, which supports the authors’ guidelines for selective flap harvesting. The technique described is safe and minimizes surgical damage.