Showing papers in "Folia Morphologica in 2006"

The biodegradation of hydroxyapatite bone graft substitutes in vivo.

Abstract: Hydroxyapatite (HA) ceramics are widely used for bone reconstruction. They are osteoconductive and serve as structural scaffolds for the deposition of new bone. Generally, scaffold materials should be degradable as they affect the mechanical properties of the reconstructed bone negatively. Degradation by osteoclasts during the bone remodelling process is desirable but often does not take place. In the current study we analysed by light microscopy the degradation of two granular HA implants in critically sized defects in the mandibula of Goettingen mini-pigs five weeks after implantation. Bio-Oss consists of sintered bovine bone and NanoBone is a synthetic HA produced in a sol-gel process in the presence of SiO2. We found that both biomaterials were degraded by osteoclasts with ruffled borders and acid phosphatase activity. The osteoclasts created resorption lacunae and resorptive trails and contained mineral particles. Frequently, resorption surfaces were in direct contact with bone formative surfaces on one granule. Granules, especially of NanoBone, were also covered by osteoclasts if located in vascularised connective tissue distant from bone tissue. However, this usually occurred without the creation of resorption lacunae. The former defect margins consisted of newly formed bone often without remnants of bone substitutes. Our results show that the degradation of both biomaterials corresponds to the natural bone degradation processes and suggest the possibility of complete resorption during bone remodelling.

Identification of greater occipital nerve landmarks for the treatment of occipital neuralgia

Abstract: Important structures involved in the pathogenesis of occipital headache include the aponeurotic attachments of the trapezius and semispinalis capitis muscles to the occipital bone. The greater occipital nerve (GON) can become entrapped as it passes through these aponeuroses, causing symptoms of occipital neuralgia. The aim of this study was to identify topographic landmarks for accurate identification of GON, which might facilitate its anaesthetic blockade. The course and distribution of GON and its relation to the aponeuroses of the trapezius and semispinalis capitis were examined in 100 formalin-fixed adult cadavers. In addition, the relative position of the nerve on a horizontal line between the external occipital protuberance and the mastoid process, as well as between the mastoid processes was measured. The greater occipital nerve was found bilaterally in all specimens. It was located at a mean distance of 3.8 cm (range 1.5-7.5 cm) lateral to a vertical line through the external occipital protuberance and the spinous processes of the cervical vertebrae 2-7. It was also located approximately 41% of the distance along the intermastoid line (medial to a mastoid process) and 22% of the distance between the external occipital protuberance and the mastoid process. The location of GON for anaesthesia or any other neurosurgical procedure has been established as one thumb's breadth lateral to the external occipital protuberance (2 cm laterally) and approximately at the base of the thumb nail (2 cm inferior). This is the first study proposing the use of landmarks in relation to anthropometric measurements. On the basis of these observations we propose a target zone for local anaesthetic injection that is based on easily identifiable landmarks and suggest that injection at this target point could be of benefit in the relief of occipital neuralgia.

High origin of a superficial ulnar artery arising from the axillary artery: anatomy, embryology, clinical significance and a review of the literature.

Abstract: The superficial ulnar artery (SUA) is an ulnar artery of high origin that lies superficially in the forearm. Its reported frequency ranges from 0.17% to 2%. During anatomical dissection in our department we observed a unilateral case of SUA in a 75-year-old white male human cadaver. It originated from the right axillary artery at the level of the junction of the two median nerve roots and followed a looping course, crossing over the lateral root of the median nerve and running lateral to it in the upper and middle thirds of the arm, whereas in the inferior third of the arm the SUA crossed over the median nerve and ran medially to it. In the cubital fossa, it passed superficially over the medial side of the ulnar aponeurosis and coursed subcutaneously in the ulnar side of the forearm superficially to the forearm flexor muscles. In the hand the SUA anastomosed with the superficial palmar branch of the radial artery, creating the superficial palmar arch. Additionally, it participated in the development of the deep palmar arch. The axillary artery, after the origin of the SUA, continued as the brachial artery and divided into the radial and common interosseous arteries in the cubital fossa. The normal ulnar artery was absent. No muscular or other arterial variations were observed in this cadaver. The embryological interpretation of this variation is difficult and it may arise as a result of modifications to the normal pattern of capillary vessel maintenance and regression. The existence of a SUA is undoubtedly of interest to the clinician as well as to the anatomist. This report presents a case of unilateral SUA along with a review of the literature, embryological explanation and analysis of its clinical significance.

An anatomical study of the origins of the medial circumflex femoral artery in the Turkish population

Abstract: The aim of this study was to investigate the origins of the lateral circumflex femoral artery (LCFA) in the Turkish population. For this purpose, we investigated 110 inguinal regions of 56 cadavers between 1997 and 2007. The LCFA was found to be branched from the deep femoral artery (DFA) in 85 (77.3%) cases and from the femoral artery (FA) in 21 (19.1%) cases. In two (1.8%) cases the ascending and the descending branches of the LCFA branched separately from the DFA and FA. There was a common trunk of the DFA and the LCFA in one (0.9%) case, and a common trunk of the DFA, LCFA and the medial circumflex femoral artery (MCFA) (trifurcation) in another (0.9%). We also measured the distance between the mid-inguinal point (MIP) and the origin of the LCFA. For LCFAs branching from the DFA the mean distance between these points was 4.8 +/- 1.2 cm, while for LCFAs branching from the FA the mean distance was 3.4 +/- 0.9 cm. We discuss the clinical importance of the artery and compare the results with the literature.

The manufacture of synthetic non-sintered and degradable bone grafting substitutes.

Abstract: A new synthetic bone grafting substitute (NanoBone®, ARTOSS GmbH, Germany) is presented. This is produced by a new technique, the sol-gel-method. This bone grafting substitute consists of nanocrystalline hydroxyapatite (HA) and nanostructured silica (SiO 2 ). By achieving a highly porous structure good osteoconductivity can be seen. In addition, the material will be completely biodegraded and new own bone is formed. It has been demonstrated that NanoBone® is biodegraded by osteoclasts in a manner comparable to the natural bone remodelling process.

The size of selected human skull foramina in relation to skull capacity.

Abstract: An anatomical study was undertaken in order to investigate whether the sizes of selected human skull foramina with significant venous compartments correlated significantly with skull capacity. A total of 100 macerated human skulls were examined to determine the diameter of the foramina and the skull capacity. Measurements of the surface area of the foramina were made using a computerised digital analysis system. Only the size of the hypoglossal canal and jugular foramen were found to correlate significantly with the capacity of the skull. This correlation, together with the considerable size of the hypoglossal canal, indicated its important role in the venous drainage of the brain. There was considerable centralisation of venous outflow from the brain, with 60% of the area of all venous foramina of the skull occupied by jugular foramina. Asymmetry between the right and left jugular foramina was identified, with an average ratio of 1.6 (ranging between 1 and 3.47). In the case of right-sided domination the correlation between the skull capacity and the size of both jugular foramina was negative (the larger the skull cavity, the less the asymmetry), while in the case of left-sided domination the correlation was positive. Perhaps the left-sided domination is less advantageous for the haemodynamics of blood outflow, as the left brachiocephalic vein is longer and is often compressed by the sternum and aortic arch.

The effects of an electromagnetic field on the boundary tissue of the seminiferous tubules of the rat: a light and transmission electron microscope study

Abstract: Human beings are unavoidably exposed to ambient electromagnetic fields (EMF) generated from various electrical devices and from power transmission lines. Controversy exists about the effects of EMF on various organs. One of the critical issues is that EMF may adversely affect the reproductive system. In order to examine this 30 rat pups were exposed to 50 Hz EMF (non-ionising radiation) during in utero development (approximately 3 weeks) and postnatal life (5 weeks). Groups of exposed rats were subsequently left in an environment free of EMF in order to observe recovery, if any, from the changes induced by EMF on the boundary tissue of the seminiferous tubules. The materials were processed and observed under a light and a transmission electron microscope. In the experimental rats boundary tissue was found disrupted at various layers. This tissue showed infoldings, which were perhaps due to the loss of collagen and reticular fibrils from the inner and outer non-cellular layers. The outer non-cellular layer, which was thinner than that of the control, was stripped away from the myoid cell layer in multiple regions, giving a "blister-like" appearance. The myoid cells showed fewer polyribosomes, pinocytotic vesicles and glycogen granules. Most mitochondria were found to lack cristae. The connections between individual myoid cells were apparently lost. There were signs of recovery in the boundary tissue following withdrawal from EMF exposure. These results suggest that EMF exposure may cause profound changes in the boundary tissue of the seminiferous tubules. Therefore exposure to EMF may result in pathological changes that lead to subfertility and infertility.

Bacterial colonisation of interior implant threads with and without sealing

Abstract: Premature loss of dental implants is due, apart from mechanical factors, to germrelated inflammation. Gaps and hollow spaces within the implant system, for example the gap between implant and abutment in the two-part implant system, may provide a bacterial reservoir causing or maintaining inflammation. The bacterial spectrum involved is similar to that found in periodontitis. This in vitro study aimed to scrutinise the capability of Porphyromonas gingivalis (DSM 20709), the bacterium blamed for inducing peri-implantitis, to pass the implant/abutment gap in titanium implant systems used for orthodontic anchorage and to remain vital in the interior. Additionally, the in vitro effectiveness of gutta percha for gap sealing was examined. Twelve titanium implants (Straumann, diameter: 3.3 mm, length 5.5 mm) were provided with abutments at a defined torque (20 Ncm), six of which were sealed with gutta percha before screwing in the abutment. Subsequently the implants were placed in a nutrient solution (thioglycolate boullion with haemin-menadione solution) that contained Porphyromonas gingivalis. Microbiological specimens were sampled from the implant interiors after 24 and 72 hours and analysed using culture methods. There was evidence that penetration of the periodontal pathogen Porphyromonas gingivalis to the implant interior may occur as early as after 24 hours. Microbes were also detected in the interior of implants sealed with gutta percha. The abutment/implant interface in vitro provides a microbiological leakage for the prospective peri-implantitis-inducing bacterium Porphyromonas gingivalis. Survival of the bacterium is possible in the interior, so that development of a bacterial reservoir is assumed. This in vitro trial produced no evidence that sealing with gutta percha is an effective means to prevent secondary bacterial colonisation in the implant interior.

An atypical position of the foramen ovale.

Abstract: Visual inspection of a dry adult human skull revealed absence of a typical foramen ovale on the left side of the cranial base. The region of the foramen ovale was covered by an osseous lamina, which was continuous with the lateral pterygoid plate and thus formed a wall of an apparent canal, which opened on the lateral side of the pterygoid process. This canal is referred to as an oval canal (canalis ovalis), instead of the foramen ovale. It runs superiorly, medially from the infratemporal fossa, and opens into the middle cranial fossa. The altered osseous morphology of this basicranial region may affect the course of the neurovascular structures which pass through the foramen ovale. As a consequence, clinical symptoms could occur, including paresthesiae of the inner aspect of the cheek and compression and neuralgia of the mandibular nerve or its branches.

An unusual course of the radial artery.

Abstract: Radial artery variations are of importance for clinicians, whether in angiographic examinations or surgical approaches. The high origin radial artery is the most frequent arterial variation observed in the upper limb, showing an incidence of 14.27% in dissection material and 9.75% in angiographic examination. In the present study an unusual course of the radial artery and its relation with the median nerve has been evaluated. During embryological development the radial artery sprouts from two arterial buds arising from the lateral side of the brachial artery and coalescing with each other. The artery lies in the forearm and is overlapped by the brachioradial muscle. In this particular case the radial artery originated from the medial side of the brachial artery and crossed the median nerve twice in an unusual manner 8 cm below the point at which the deep brachial artery arose and 12 cm above the intercondylar line. These results will enhance anatomical knowledge of the region and reduce complication in surgical approaches.

The level of chemokine CXCL5 in the cerebrospinal fluid is increased during the first 24 hours of ischaemic stroke and correlates with the size of early brain damage.

Abstract: Inflammation is an important feature of the pathophysiological response to ischaemic stroke. The ischaemic brain-invading leukocytes, neutrophils in particular, contribute to the exacerbation of tissue injury in stroke. Chemokines are a growing family of proteins performing chemotactic activity on selective leukocyte subpopulations. Chemokines are broadly divided into two major subfamilies on the basis of the arrangement of the two N-terminal cysteine residues, CXC and CC, depending on whether the first two cysteine residues have an amino acid between them (CXC) or are adjacent (CC). CXC chemokines possessing, close to the N terminus, the amino acid sequence glutamic acid-leucine-arginine (ELR motif) specifically act on neutrophils. CXCL5 is one of the ELR-expressing CXC chemokines and is a potent neutrophil attractant and activator. The objective of the study was to detect CXCL5 levels in the cerebrospinal fluid (CSF) and sera of stroke patients and to investigate the relation between these levels and the volume of brain computed tomography (CT) hypodense areas representing early ischaemic lesions. A total of 23 ischaemic stroke patients were studied. CSF and blood sampling and brain CT were performed within the first 24 hours of stroke. The control group consisted of 15 patients with tension headache. CXCL5 levels were determined by the ELISA method. CSF CXCL5 levels in stroke patients were significantly higher in comparison with the control group (38.2 +/- 18.4 pg/ml vs. 18.7 +/- 8.2 pg/ml; p < 0.001). No significant differences in serum CXCL5 levels were found between the stroke patients and the control group. CSF CXCL5 levels correlated positively with the volume of early brain CT hypodense areas (p < 0.0001). The results suggest that CXCL5 may play a role in the inflammatory reaction during the early phase of ischaemic stroke.

The reproductive toxicity of the organophosphate pesticide O, O-dimethyl O-4-nitrophenyl phosphorothioate (methyl parathion) in the male rat

Abstract: Methyl parathion (MP) is a pesticide widely used to protect crops but also illegally used in many countries for spraying homes and businesses to contain insects. The present study was planned to investigate the effects of MP on the male reproductive organs in the rat. Male Wistar rats (13–14 weeks old) were treated with MP and sacrificed as follows. Experiment 1: 0 (water vehicle), 1.75, 3.5 or 7 mg/kg (i.p.) for 5 days and sacrificed on day 14; experiment 2: 0, 0.5 or 1 mg/kg (i.p.) for 12 days and sacrificed on day 130; experiment 3: 0, 0.5 or 1 mg/kg (i.p.) for 12 days and sacrificed on day 77; experiment 4: 0, 0.75 or 1.5 mg/kg (i.p.) for 25 days and sacrificed on day 17; experiment 5: 0 or 3.5 mg/kg (p.o.) for 25 days and sacrificed on day 17 after the last exposure. The reproductive organs were removed, weighed and processed for histopathological analysis. Structural changes, for example the morphology of the epithelium and the lumina of the organs, were observed in all animals. Biochemical estimates of acid phosphatase (ACP), cholesterol, total protein, uric acid, and vitamin C were conducted in the epididymes. The weight of the epididymes increased in experiment 2 in a dose-dependent pattern (p < 0.01) and decreased in experiments 4 and 5 (p < 0.01). The weight of the ductus deferens decreased in experiment 3 at 1 mg/kg dose level (p < 0.001) and increased in experiment 5 (p < 0.05). The weight of the seminal vesicle decreased in experiment 3 at both 0.5 mg/kg and 1 mg/kg dose levels (p < 0.001), and increased in experiment 5 (p < 0.01). The weight of the prostate decreased in experiments 4 (in a dose-dependent pattern)and 5 (p < 0.001). ACP levels decreased in experiment 4 (p < 0.001) with a greater effect at 0.5 mg/kg than at 1 mg/kg. In experiment 5 (p < 0.01) cholesterol levels decreased to less than 50% of the control level for this experiment (p < 0.01) and protein levels also decreased (p < 0.01). Vitamin C levels decreased in a dose-dependent pattern in experiments 4 (p < 0.001) and 5 (p < 0.01). There were no effects on uric acid level. Sperm density was decreased in the epididymes of the rats treated and the epithelium of the epididymis and ductus deferens showed cellular necrosis, brush-border disruption and nuclear pyknosis. Nuclei were haloed, except in experiment 2 and the 0.5 mg/kg group of experiment 3. Methyl parathion did not induce significant changes in the structure of the seminal vesicle and prostate, except that epithelial folding was shorter than in the control. In conclusion, MP is a reproductive toxicant in the male rat and causes deterioration in the structural integrity of the reproductive organs and also the biochemical parameters in the epididymis

Absence of the musculocutaneous nerve together with unusual innervation of the median nerve

Abstract: During routine anatomical dissections, absence of the musculocutaneous nerve was determined in a 58-year-old male cadaver. Moreover, the biceps brachii and brachialis muscles were innervated by two separate branches which divided from the median nerve instead of the musculocutaneous nerve. From a branch that divides from the main trunk of the median nerve at nearly the middle of the arm a motor branch again divided that innervated the brachialis muscle and a sensory branch that conveyed the sense of the lateral part of the forearm. Furthermore, it was found that the brachial artery divided into its terminal branches, the radial and ulnar arteries. We believe that this rare variation of the median nerve will shed light upon surgical procedures involving the median nerve.

The ossified interclinoid ligament.

Abstract: The paper presents an anatomical description of the ossified interclinoid ligament which was found in a male human skull. In the case studied the ossified ligament exists as a bony bridge between the anterior and posterior clinoid processes on the left side of the skull. The length of this connection was measured as 5.0 mm, while its thickness was 3.2 mm. We conjecture that the presence of a considerably thick bony trabecula within the sella region might have had an impact on the course of the internal carotid artery or the oculomotor nerve, causing compression of these structures.

A complex variation in the superficial palmar arch.

Abstract: In this article we describe a unique and complex variation in the arterial pattern of the left hand of a female cadaver. The following variations were found in this case: a) persistent median artery of the palmar type, terminating in the hand as the princeps pollicis and radialis indicis arteries; b) the ulnar artery giving only two common palmar digital arteries; c) the second digital palmar artery without division into two digital branches and instead supplying only the radial side of the ring finger; d) absence of the first common digital artery with the contiguous sides of the second web space supplied by the first palmar metacarpal artery from the deep palmar arch; e) early bifurcation of the median nerve proximal to the flexor retinaculum.

The morphology of the right atrioventricular valve in the adult human heart.

Abstract: Studies of the morphometry and normal anatomy of the tricuspid valve are in constant demand. Knowledge of the morphology of the normal tricuspid valve may be useful, for example in the context of the transfer of a leaflet of the tricuspid valve for repair or insufficiency of the mitral valve, in repair of the tricuspid valve after blunt chest trauma and in other surgical techniques of this region. In this study, performed in a group of 107 formalin-fixed adult human hearts, we attempted to assess the form and number of the main and accessory cusps in the tricuspid valve. Rare anatomical variants of the tricuspid valve were found. Using a planimeter we evaluated the surface area of the tricuspid valve and particular leaflets. With the help of a Vernier scale we measured the length and height of individual leaflets of the tricuspid valve and the length of the commissures. No differences were found between the length of the anterior and septal leaflets. The posterior leaflet was the shortest, while the anterior leaflet was the widest and had the largest surface area. The posterior leaflet was wider than the septal leaflet and had the smallest surface area. No differences were found between the main and accessory leaflets in the length of the commissures.

Dermal exposure to the herbicide-paraquat results in genotoxic and cytotoxic damage to germ cells in the male rat

Abstract: The effects of exposure to low doses of paraquat, a herbicide, via the dermal route were studied on the spermatozoa of Sprague-Dawley rats. Paraquat (1, 1’-dimethyl-4, 4’-bipyridinium dichloride) was administered once a day for five days, at intervals of 24 h at 0, 6, 15 and 30 mg/kg, and the rats were sacrificed on days 7, 14, 28, and 42 after the last exposure. The sperm suspensions were obtained by mincing the caudae epididymes and ductus deferens for the purpose of performing a sperm morphology test, sperm count and analysis of sperm mortality and sperm motility, as per the standard procedures. The sperm count was decreased (p < 0.05) only on days 7 and 14 but sperm abnormalities increased on all days (p < 0.05). Sperm mortality increased at higher dose-levels (p < 0.05) except on day 42, and motility was affected by 30 mg/kg only on day 42. In conclusion, paraquat is a genotoxic and cytotoxic agent to germ cells in the male rat.

The ultrastructure and processing properties of Straumann Bone Ceramic and NanoBone.

Abstract: The ultrastructure, fundamental chemistry, and processing modes of fully synthetic bone grafting materials are relevant to the reconstruction of osseous defects. Rapid progress in the profitable market of biomaterials has led to the development of various bone substitutes. Despite all these efforts, an ideal and full substitute of autologous bone is not yet in sight. With regard to anorganic calcium phosphate ceramics, Straumann Bone Ceramic® and NanoBone® are compared. These have a similar composition and are osteoconductive, which indispensably requires contact with well-vascularised bone.

Neonatal methyl parathion exposure affects the growth and functions of the male reproductive system in the adult rat.

Abstract: Methyl parathion (MP) is a well-known organophosphorus pesticide, to which humans are exposed in fruit and vegetables as residues of 0-2 mg/kg, children being at higher risk of exposure. The present study was planned to investigate the effects on the adult male reproductive functions of MP following neonatal exposure. New born male Wistar rat pups were treated orally with either 0 or 0.5 mg/kg MP from postnatal day (PND) 3 to PND 28 and sacrificed on PND 98 for the purpose of examination of the reproductive system. Methyl parathion lowered the body weights from days 10 to 24 (p < 0.01), the weights of the reproductive organs (p < 0.05-0.01), the epididymal sperm count (p < 0.01) and the homogenisation-resistant testicular spermatid head count (p < 0.01) and also decreased acid phosphatase (ACP), cholesterol, uric acid, protein, ascorbic acid, and lactate dehydrogenase (p < 0.01) levels in the testis but only ACP and cholesterol in the epididymis. The levels of abnormal sperm and testosterone in the testis were increased (p < 0.01), whereas the leutinising hormone level and total number of seminiferous tubules decreased in the testes of treated rats (p < 0.01). A few tubules showed exfoliation of epithelium and vacuoles. The incidence of stage XIV tubules and ratios of meiotic figures and elongating spermatids to Sertoli cell nucleoli decreased (p < 0.01; Mann-Whitney U test). The present results indicate that MP acts as an endocrine disruptor and consequently affects the postnatal development and growth of the male reproductive organs in the rat. These findings are important to the general public, as there is a chance of children being exposed to this pesticide.

A study of the discomalleolar ligament in the adult human

Abstract: The discomalleolar ligament (Pinto’s ligament) is not described in the anatomy textbooks but was demonstrated by Pinto and others. This is a ligamentous structure connecting the malleus in the tympanic cavity and the articular disc and capsule of the temporomandibular joint. This anatomical relationship between the middle ear and the temporomandibular joint is supposed to be one of the explanations for the aural symptoms associated with temporomandibular joint dysfunction. The objectives of our study were to determine: (1) the frequency of occurrence and morphology of the discomalleolar ligament, (2) its attachments, (3) the morphology of Pinto’s ligament in endoscopic visualisation, and (4) whether tension applied to the discomalleolar ligament could elicit movement of the malleus. Fourteen adult human temporomandibular joint and tympanic cavity specimens were examined with the use of an endoscope and then by gross dissection with the superior approach and with the use of the operating microscope. Endoscopic visualisation showed in four cases a band of tissue in the upper temporomandibular joint compartment, known as Pinto’s ligament. The dissections exposed a discomalleolar ligament in 11 specimens. We were able to identify two main types of this ligament on the basis of its shape. The discomalleolar ligament was either triangular in shape, as in the first group of seven specimens, or longitudinal in shape, as in the second group of four specimens. We observed that tension applied to the discomalleolar ligament resulted in movement of the malleus in three specimens.

A case of an anomalous pectoralis major muscle.

Abstract: We present a case of a right sided accessory head of the pectoralis major muscle located inferior to its abdominal head. This variation was found during a routine anatomy dissection at the American University of the Caribbean School of Medicine. The muscle fibres of the accessory head of the pectoralis major muscle arose from those of the serratus anterior muscle and travelled superolaterally towards the axilla. The accessory muscle terminated by fusing with the tendinous fibres of the pectoralis major muscle as they underwent their normal anatomical rotation before insertion upon the lateral lip of the bicipital groove of the humerus. Although variations in the pectoral muscles are not uncommon, this case appears to be unique in the literature. The possible clinical implications are discussed.

A rare variation of the vertebral artery.

Abstract: Variations of the vertebrobasilar arterial complex are important with regard to their potential clinical impact. We present an unusual case of the vertebral artery, in which the left vertebral artery in its ascent in the neck through the transverse foramina passed posteriorly between the transverse processes of C3 and C4 and supplied the posterior muscles of the neck without continuing intracranially. Albeit speculatively, we hypothesise that the variation of the vertebral artery reported here was caused by degeneration of the proximal portion of the left postcostal longitudinal anastomosis (i.e. C1 and C2 intersegmental arteries) in the context of a persistent third cervical intersegmental artery. Our case is unique in that the left vertebral artery terminated extracranially. Knowledge of the variations of the vertebrobasilar arterial complex is important for surgeons operating at the skull base, craniocervical junction, and cervical region, and for clinicians interpreting the imaging of this region.

The clinical application of a new synthetic bone grafting material in oral and maxillofacial surgery.

Abstract: A novel bone formation material based on hydroxyapatite-xerogel is presented. With the use of the innovative sol-gel technology this material is produced in the low-temperature range by the addition of silicon dioxide; in its structure it mimics to a great extent the natural bone matrix. This results in high osteoconductivity and an osteoprotective effect as well as in complete biodegradation corresponding to bone formation in the course of natural bone remodelling. Two case reports are presented.

A contribution to the discussion concerning the variability of the third peroneal muscle: an anatomical analysis on the basis of foetal material.

Abstract: The aim of the work was to make a systemic study of the variability of the human musculus peroneus tertius during the foetal period. Examination was made of 193 foetuses of ages ranging from 84 to 256 days after conception. The results obtained indicated that the musculus peroneus tertius was present in 83.16% of the human foetuses studied and that its intrauterine development was progressive and almost proportional. Previous studies have not revealed dimorphic or bilateral differences with respect to any of the features examined. On the basis of the examinations and bibliographical data a uniform typology of the musculus peroneus tertius variants was created and three final types were distinguished: the pithecogenic (44% cases), eugenic (34% cases) and progenic (22% cases).

The in vitro viability and growth of fibroblasts cultured in the presence of different bone grafting materials (NanoBone and Straumann Bone Ceramic).

Abstract: Different clinical applications, including dentistry, are making increasing demands on bone grafting material In the present study we have analysed the viability, proliferation and growth characteristics of fibroblasts cultured in vitro together with two different bone grafting materials, NanoBone® and Straumann Bone Ceramic®, over a period of 24 and 28 days respectively Viability was measured at least every 72 hours by using the alamarBlue assay, a test that measures quantitatively cell proliferation and viability but does not require cell fixation or extraction After one week of culture fibroblast viability was as high as in controls for both grafting materials and remained high (> 90%) for the duration of the experiment Cell growth was evaluated microscopically Scanning electron microscopy revealed a dense fibroblast growth at the surface of both bone grafting materials after three weeks of in vitro culture Generally, our in vitro analyses contribute to further insights into cell - scaffold interactions

An angiographic study of the anterior tibial artery in patients with aortoiliac occlusive disease.

Abstract: The anterior tibial artery is of great clinical relevance to vascular infrapopliteal surgery. The sources (origins), length and luminal diameter of the anterior tibial artery in 46 men and 30 women with Lerich syndrome were studied by means of radiological and digital methods. The results obtained were described by twoway analysis of variance (Multi-group ANOVA) for unpaired data — the means for six subtypes with regard to sex and side of the body, using the STATISTICA 5.5 program. The anterior tibial artery occurred most frequently (92.11%) as a terminal branch of the popliteal artery in its normal (IA: 87.5 %, IB: 2.63%) and high (IIA 1: 1.32%, IIA 2: 0.66%) division. In the remainder (7.89%), the anterior tibial artery arose from both the anterior tibioperoneal trunks (IC: 1.97%, IIB: 5.92%). The statistical analysis of the sources of the anterior tibial artery did not show gender differences. Symmetry of the left and right popliteal patterns was observed in the two most frequent subtypes: IA (r 1 = 0.80) and IIB (r 2 = 0.83). The anterior tibial artery was the longest (p = 0.02 for men, p = 0.04 for women) in subtype IIA 2. The greatest diameter of the anterior tibial artery was characteristic for a trifurcation (IB) and the smallest for subtype IIA 2 (p = 0.04). Both the length (p = 0.03) and luminal diameter (p = 0.04) of the anterior tibial artery in men were significantly greater than in women in all the popliteal subtypes observed. Morphometric parameters of the right and left anterior tibial artery showed no statistically significant differences. The anterior tibial artery was the predominant vessel in a trifurcation (IB) and in the two subtypes with an anterior tibioperoneal trunk (IC, IIB). These results have implications in vascular grafting below the knee.

A case of atypical insertion of the levator scapulae

Abstract: Anatomical variations in the musculature of the spine have the potential to cause functional and postural abnormalities, which in turn could lead to chronic myofascial and skeletal pain. We present a unilateral case of a 71-year-old Caucasian female in which the left levator scapulae muscle gave rise to an accessory head that inserted, by way of a flat aponeurotic band, to the ligamentum nuchae, the tendon of the rhomboideus major and the superior aspect of the serratus posterior superior muscle. The innervation was provided by a branch of the dorsal scapular nerve. By exerting unilateral traction on the vertebrae and surrounding musculature, this unusual variation might have resulted in clinical consequences including scoliosis and movement abnormalities of the head and neck as well as myofascial pain syndrome.

The pinealocytes of the human pineal gland: a light and electron microscopic study

Abstract: The pinealocytes of the pineal gland of children and adults were studied at both light and electron microscopic levels. The pinealocytes were classified into light and dark pinealocytes on the basis of their shape, nuclear infolding, cytoplasmic contents and staining density. The light pinealocytes outnumber the dark pinealocytes and both of them have thin processes. The light pinealocytes have round or oval cell bodies and nuclei and have vesicles and ribbons. The dark pinealocytes showed more variations in their shape. The nuclear membrane of the dark cells showed numerous infoldings with deep invagination of parts of the cytoplasm within the nuclear folds, giving the appearance of nuclear pellets. The dark pinealocytes contain pigment in their cytoplasm. In addition to the light and dark pinealocytes a very small cell type with an extremely thin and elongated cell body and nucleus was found. The cells of this type were almost always associated with vacuoles filled with flocculent material and accumulations of presumptive secretion in the extracellular compartment. The findings of this study were discussed in the light of the published data about the pinealocytes of human and non-human species.

Does a third head of the rectus femoris muscle exist

Abstract: Current anatomical texts describe only two tendinous origins of the rectus femoris muscle. The authors identified one older reference in which a third head of the rectus femoris muscle was briefly described. In order to confirm the existence of this head, 48 adult cadavers (96 sides) underwent detailed dissection of the proximal attachments of the rectus femoris muscle. Of these sides 83% were found to harbour a recognised third head of the rectus femoris muscle. This additional head was found to attach deeply to the iliofemoral ligament and superficially with the tendon of the gluteus minimus muscle as it attached into the femur. This tendon attached to the anterior aspect of the greater trochanter in an inferolateral direction compared to the straight head. The mean length and width of the third head was 2 cm and 4 cm, respectively. The mean thickness was found to be 3 mm. Most commonly this third head was bilaterally absent or bilaterally present. However, 4.2% were found only on left sides and 5.2% were found only on right sides. The angle created between the reflected and third heads was approximately 60 degrees. Two sides (both left sides with one female and one male specimen) were found to have third heads that were bilaminar. These bilaminar third heads had a distinct layer attaching to the underlying iliofemoral ligament and a superficial layer blending with the gluteus minimus tendon to insert onto the greater trochanter. Although the function of such an attachment is speculative, the clinician may wish to consider this structure in the interpretation of imaging or in surgical procedures in this region, as in our study it was present on the majority of sides.

A rare variation of the posterior cranial fossa: Duplicated falx cerebelli, occipital venous sinus, and internal occipital crest

Abstract: Folds of the meningeal layer of the dura mater, the falx cerebri and tentorium cerebelli, traverse the vertebrate intracranial cavity and thus compartmentalise the brain. The falx cerebelli, another dural fold, is found in the posterior cranial fossa and attaches to the inferior aspect of the tentorium cerebelli and to the internal occipital crest. We present a case of a duplicated falx cerebelli, occipital venous sinus and internal occipital crest that was detected upon routine dissection of a male cadaver. Since haemorrhage of a dural venous sinus can be a fatal complication of posterior cranial fossa surgery, knowledge of venous sinus variations in this region may prevent unpredictable complications during intracranial procedures.