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Biomedical subjects

W Lierse

Publications and source records attributed to W Lierse.

At least 19 recordsLinked to original sources
PubMed1992

[The arterial blood supply of the tibial and practical consequences].

In the periosteum of the human tibia, the arterial blood supply shows a general sectorial angioarchitecture. There are 4 segments: proximal and distal 1/5, proximal and distal diaphysis. The proximal 1/5 of the tibial periosteum is supplied with blood by the aa. recurrentes tibiales anterior et posterior and the aa. inferiores medialis et lateralis genus. At the proximal diaphysis (next 3/10 of the tibia) periosteal branches arise from the a. tibialis anterior and the a. tibialis posterior. The distal diaphysis (following 3/10 below the middle of the tibia) is nourished exclusively by semicircular rami periostales of the a. tibialis anterior, which move around the bone from both sides and join with each other at the facies medialis. It is the only sector, which is supplied by a single main artery. Concerning the periosteal blood supply of the distal 1/5 of the tibia 2 different types are found. In 2/3 of the cases the lateral side is nourished by a great vessel of the a. fibularis, which is supported by branches arising from the a. tibialis anterior. In 1/3 of the cases this vessel of the a. fibularis is absent and rami periostales of the a. tibialis anterior nourish the lateral aspect of the distal tibia alone. The dorsal region is supplied in all cases by rami of the a. fibularis and a. tibialis posterior. On the medial side the periosteal nourishment is ensured only by anastomoses. Both the facies lateralis and the facies posterior are supplied by direct branches, which arise from the main arteries of the lower leg.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Autologous rib perichondrial grafts in experimentally induced osteochondral lesions in the sheep-knee joint: morphological results.

The purpose of the present study was to examine the fate of autologous perichondrial grafts after transplantation into cartilage lesions in weight-bearing joints. Osteochondral lesions were made in the articular surface of knee joints in 36 sheep. The defects were filled with autologous rib perichondrial grafts which were secured by either collagen sponges (12 animals) or fibrin glue (12 animals). Defects without perichondrial grafts served as controls (12 animals). Following 1 week of immobilization of the operated leg, the plaster was removed and the animals were allowed to move freely. Animals were sacrificed after 4, 8, 12 and 16 weeks. The grafts were removed and investigated histologically. In contrast to weight-bearing areas and control defects, hyaline-like cartilage formation was seen in non-weight-bearing areas after 4 weeks. This newly formed cartilage revealed strong metachromasia following staining with acidic toluidine blue and reacted positively with periodic acid-Schiff, indicating de novo synthesis of proteoglycans and glycoproteins. Scanning electron microscopy and examinations with polarized light confirmed a hyaline cartilage-like architecture for the surface area as well as for the fibre orientation of the whole graft. Enzyme histochemistry for alkaline and acid phosphatase activity showed positive reactivity only at the base of the transplants.

Animals↗
PubMed1992

[Design of a tibial intramedullary nail based on anatomic studies of intraosseous vessels].

The design of the tibial medullary nail can be improved in order to preserve intraosseus vessels by osteosynthesis of the tibia. The nutrient artery of the human tibia enters the compacta in an average height of 33% dorsally and is leaving it in a height of 50% of the tibial length. In the medullary cavity the vessel splits up. The main branch continues the distal course on the dorsal/dorsolateral side of the medullary cavity (endosteal). In the distal diaphysis this endosteal vessel is of great importance, since the periosteal blood supply in this region with high incidence of pseudarthrosis is guaranteed only by branches of the anterior tibial artery. Using a new unreamed tibial nail, which is flattened dorsally, it is possible to preserve the endostal main artery of the tibia.

Aged↗
PubMed1992

The physiology and pathology of the esophagus.

The esophagus and trachea derive from the foregut during the 4th week of development and is constructed as a part of the gut: longitudinal and circular muscle bundles are connected to a functional system together with collagen and elastic fibers. The action of the cricopharyngeal "pinch-cock" is pronounced in the newborn. In the region of the upper orifice ganglion cells are absent and venous vessels are oriented in a longitudinal direction. The myoelastic fiber system is in the lower part of the esophagus arranged as a stretching system, and the esophagus becomes longer and narrower by traction. The blood vessels derive from the thyroid arteries, the aorta, the bronchial arteries, the left gastric artery and the left inferior phrenic artery. Poor zones of vascularity are in the middle of the ventral and dorsal plane.

Embryonic and Fetal Development↗
PubMed1992

Sectorial angioarchitecture of the human tibia.

The blood supply of the periosteum of the human tibia was investigated by anatomical dissection of 12 lower extremities which were filled with injection mass. By division of the tibia into 4 segments (proximal and distal fifths; proximal and distal diaphysis) a general supplying system of the periosteum was found. The proximal fifth of the tibial periosteum is nourished by branches of the arteriae recurrentes tibiales anterior et posterior and the aa. inferiores medialis et lateralis genus. At the proximal diaphysis (next three tenths of the tibia) periosteal branches arise from the aa. tibialis anterior and posterior, whereas the distal diaphysis is nourished exclusively by semicircular vessels of the a. tibialis anterior which twine around the bone and merge with each other at the facies medialis. Concerning the periosteal blood supply of the distal fifth of the tibia, two different types were found. In two thirds of the cases the lateral side was nourished by branches of the a. tibialis anterior, which are supported by vessels from the a. fibularis. In one third the latter branch was absent so that the rami periostales arising from the a. tibialis anterior nourished the lateral aspect of the distal tibia alone. The dorsal region was supplied in all cases by rami of the a. fibularis and a. tibialis posterior. On the medial side the periosteal nourishment is ensured only by anastomosis. Branches of the a. tibialis anterior supply the facies lateralis and facies posterior where it is supported by vessels of the a. tibialis posterior and in a minor region of rami of the a. fibularis (distal) and a. poplitea (proximal).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Functional construction of the sacroiliac ligamentous apparatus.

The sacroiliac ligamentous apparatus was examined as a part of a biomechanical pelvis-lower extremities system. The ligamentous apparatus of two pelves was freed, and the findings concerning the ligaments and their direction were drawn by a modular constructed, three-dimensional calculator model of the pelvic region. The ligamentous apparatus of the sacroiliac joint belongs to a functional system. Its task is to minimize every movement in this amphiarthrosis. The ligamentous apparatus shows an adaptation to strong or long-time-acting stresses. The junction between the os sacrum, pelvis and the ligamentous apparatus of the sacroiliac joint can be described as self-tightening. Local stresses are also reduced by the ligaments. A loosening in this system, which has to fix the os sacrum to the pelvic girdle, leads to a static insufficiency. The consequence is pain due to an irritation of the lumbosacral trunk. The exact description of the structure allows a representation according to the laws of similarity mechanics. With such a representation one can build up a computer-aided biomechanical model of the pelvis-lower extremities region. Examples for such a model are biomechanical finite-element models. By observing the laws of similarity mechanics (an exact description of geometric, physical and functional conditions) an efficient biomechanical model can be constructed that also takes into consideration the complex functional circumstances, in contrast to previous models. In order to construct such a model, one has to feed the findings of the examination into a data bank, which has to be demanded.

Biomechanical Phenomena↗
PubMed1991

Intraperitoneal hepatocyte transplantation: morphological results.

The value of isolated intraperitoneal hepatocyte transplantation as a temporary support in acute hepatic failure is controversial since the functional capacities and survival rate of auxiliary transplanted liver cells are uncertain. It was the aim of this study to investigate the survival rate of intraperitoneally (i.p.) transplanted hepatocytes and microcarrier attached hepatocytes. In 25 rats (group A) an i.p. hepatocyte transplantation and in 30 rats (group B) an i.p. microcarrier attached hepatocyte transplantation was performed and the animals were killed at 3 h, 12 h, 24 h, 3 and 7 days (group A) and 1, 2, 3, 7, 14 and 28 days (group B) after transplantation. Histological investigation showed that transplanted hepatocytes undergo complete cell necrosis within 3 days (groups A and B). Liver cell necrosis was followed by a peritoneal reaction resulting in granuloma formation in both groups. Since liver cell necrosis occurred soon after transplantation and could not be avoided by attachment of liver cells to microcarriers, it can be concluded that metabolic support from transplantation cannot be expected in acute hepatic failure.

Animals↗
PubMed1991

Morphometric evaluation of chondrocyte cavities in normal and prearthrotic human femoral heads.

In 25 human femoral heads, the structural changes in the chondrocyte cavities of prearthrotic cartilage were determined in three different layers by detailed morphometric evaluation. As examination parameters, the area, perimeter, diameter, and the form deviation from a circle (form PE) were chosen. In addition, we calculated the numeric cell density and the mean distance between two chondrocyte cavities. For intraindividual comparison, the same data were obtained from nondegeneratively changed cartilage areas of each femoral head. The main arthrotic regions were located in the weight-bearing area of the femoral head, particularly in the dorso- and ventrolateral quadrants. The number of chondrocyte cavities as well as the numeric cell density were decreasing from superficial to basal layers, whereas the mean distance between two chondrocyte cavities was increasing. Concerning these parameters, no significant differences were seen between the prearthrotic and control groups. We found that the chondrocyte cavities in the superficial layer in prearthrotic areas show a tendency to smaller volumes in comparison with nondegeneratively changed areas, whereas in the basal layer, no difference could be seen. We presume that the changes in the articular cartilage are not related to an insufficient supply of the cartilage with nutriments, but probably to the high mechanical strain applied to its surface.

Aged↗
PubMed1991

[Angioarchitecture of the cricoid cartilage and anterior trachea].

Two dense capillary networks have been described lying in the anterior and posterior parts of the human cricoid cartilage. Between these two lies an area supplied by a very sparse capillary network. The anterior sector is derived from branches of the cricothyroid and inferior laryngeal arteries, the posterior from branches of the superior and inferior laryngeal arteries. The tracheal cartilages are supplied from above downwards by circular branches derived from two parallel longitudinal arteries. Therefore the centre of each cartilage is very sparsely supplied by small arteries.

Aged↗
PubMed1991

[The fascia of the inguinal canal ring].

The fascial anatomy of the inguinal canal has been investigated. The spermatic cord is fixed by two cords in addition to its embedding in connective tissue after leaving the inguinal canal. The spermatic cord has a special fastening in form of a noose at the deep inguinal ring. The transversalis fascia consists of an internal and an external leaf. A part of the internal leaf forms with three cords this noose and builds so a sphincter-like closure mechanism, which reduces the size of the deep inguinal ring by a local erection of the transversalis fascia. The internal leaf protects from an indirect inguinal hernia as well as from a direct inguinal hernia, because the wall of the so-called Hesselbach's triangle only consists of the internal leaf. A list of the anatomical synonyms is added.

Abdominal Muscles↗
PubMed1991

[CCL-tensulae in the skeleton as part of a hydrodynamic skeletal system].

Previous morphological studies on human bone have demonstrated that veil-like structures ('tensulae') occur in highly stressed regions, i.e. the interface between cartilage and bone. In the present report we describe the distribution of tensulae within various types of human bone by means of scanning electron microscopy and light microscopy. Tensulae were predominately located within bone tissue adjacent to mineralized cartilage. The surface diameter of tensulae ranged from minimal 50 to maximal 400 microns. Occasionally, collagen fibers extended from the interface between cartilage and bone to tensulae. Frequently, the latter were attached to fat cells as well as bone marrow cells. An elemental analysis of tensula revealed high levels of calcium and phosphorus of equal concentrations. However, bone tissue contained higher levels of calcium compared to phosphorus. Additionally, a monoclonal antibody was generated by immunizing rats with bone marrow of mice. Within bone tissue this monoclonal antibody selectively stained membrane-like structures which were clearly identified as tensulae. From our investigations we conclude that the function of tensulae in bone may be to absorb stress in regions where large forces are applied.

Animals↗
PubMed1990

[The course of fibers in the central tendon].

In each polytrauma a diaphragmatic rupture is possible. Usually the rupture is located in the central tendon. A cause of the bizarre form of ruptures is the individual arrangement of gaps between the fibres of the central tendon. These fibres are classified in three groups. A rupture is generally on the left side of the central tendon. A further cause of the relative rare rupture on the right side is beside protection by the liver the greater stability on the right side of the central tendon, because fibres are more interlocked. The diaphragmatic rupture of a polytrauma is often overlooked, this number could be reduced by specific diagnostics. The repair of a diaphragmatic rupture is not a problem, an abdominal approach should be preferred. The prognosis depends on extension of concomitant lesions.

Aged↗
PubMed1990

[Detection of hydrodynamically operative tissue in the substantia spongiosa of the femoral head in Bos taurus and Ovis aries].

The authors show the presence of CC-Tensulae in Bos taurus and Ovis aries. They define CC-Tensulae as tense membranes in openings between the trabeculae of spongy bone. These structures were interpreted in man as a hydrodynamic subsystem which serves the flow and the impulses of mechanical forces. The authors point especially to the similarity that exists between their findings and what has been seen in man.

Animals↗
PubMed1990

Functional construction of the superficial and deep fascia system of the lower limb in man.

The muscular system, the connective tissue and the bones are the components of a biomechanical pelvis-lower extremity model. The occasional electrical events in the muscles were not taken into account, as they can only be measured by physiological methods. In this publication, the connective tissue of the lower extremities is examined. The connective tissue system of the thigh and leg was prepared; after removal of the muscles the so-called 'hollow' lower extremity could be studied. A topographical documentation followed, and the structure and directions of the fibers were observed with polarized light. The connective tissue systems of the lower extremities and bones form a biomechanical, effective and functional system, the bone-fascia-tendon system. The components of the connective tissue in such a system are the fascia lata, the crural fascia, the iliotibial tract, the femoral and crural intermuscular septa, and the membrana interossea. The iliotibial tract is not the sole part of this system having a tension band effect, other components--above all the lateral femoral intermuscular septum--also reduce the forces acting on the bones. Therefore, the tensile strength of the iliotibial tract has to be considered lower as supposed. The iliotibial tract is not a part of the fascia lata; it is an independent, vertically tightened tendon of the 'pelvic deltoid muscle' (gluteus maximus, tensor fasciae latae). The iliotibial tract passes over the greater trochanter like on a roller bearing. It is not attached directly to the greater trochanter and to the lateral femoral condyle, so that previous models have to be modified. The iliotibial tract glides in a fascia bag which is composed of oblique and horizontal fibers of the broad fascia. The iliotibial tract, as tendon of the pelvic deltoid muscle, continues in a lateral location into the leg where it is fixed to the lateral malleolus. The present report provides a new description of the structure of the connective tissue system of the lower extremities. The model reported complies with the laws of similarity mechanics by describing exactly the geometric, physical and functional conditions. This representation could facilitate the construction of a computer-aided, efficient, biomechanical model of the pelvis-lower extremity region considering also the complex functional circumstances, in contrast to previous models. In order to construct such a model, the data obtained by the examination of the connective tissue of the lower extremities have to be given into a data bank, which, however, has to be built up.

Biomechanical Phenomena↗
PubMed1990

[Ultrastructure of the substantia spongiosa of the femur head and talus].

The results of the SEM examination of the zone between the cartilage and the spongeous substances are described precisely. For the first time, W. Lierse examined the 'tensulae' of calcium-collagen lamellae by light microscopy. The examination of this zone was initiated by the fact that the hydrodynamic flow can take place in the calcified zone of the cartilage which is filled with synovial fluid and that the calcified zone adheres to the subchondral substantia corticalis. The subchondral corticalis is characterized by funnel-like indentations with a high number of calcium-collagen and chondrocyte 'tensulae' which are up to now uncounted. The special aim was to locate the separation of the space of adipose and arterial supplies.

Calcium↗
PubMed1990

[The anatomy of the pelvis].

The pelvis consists of the sacrum, the ossa coxae, and additionally the ligaments between these bones. According to mathematical calculations the bony structure as well as the arrangement of ligaments result in optimal engineering principles, i.e. maximal strength is achieved by minimal principles, i.e. maximal strength is achieved by minimal material. The muscles inside the pelvis are covered by a fascial layer. The latter represents a continuation of the abdominal transversal fascia which extends to the pelvic floor. The connective tissue fibres around the pelvic viscera interweave with those of the pelvic floor and laterally with the connective tissue around vessels and nerves. Connective tissue around the neurovascular sheaths is nearly transversely arranged and forms the lateral ligaments of bladder, uterus or prostate gland and the rectum. Several vertically arranged connective tissue ligaments accompany either the superior rectal artery and hypogastric nerves or the ureter and the ovarian vessels. Therefore, the lymphatic fluid of the pelvic organs passes the aortic lymph nodes and/or to the lateral pelvic wall along the branches of the internal iliac vessels.

Humans↗