Individual Anatomical Variability Research Articles

MORPHOMETRIC CHARACTERISTICS OF NECK PARAMETERS IN THE PERINATAL PERIOD OF ONTOGENESIS

This study aims – to establish the normative morphometric parameters of the neckcircumference, anterior- posterior diameter, height, and width during the perinatal periodof ontogenesis, after which the parameters will be used to construct anatomical models. Material and Methods. The study was conducted on 63 human fetuses aged 4 to10 months and 7 newborns (including 5 isolated organ systems). To create anatomicalmodels, the well-known dimensions of the neck in all age groups were determined usinga centimeter tape and a caliper. The neck circumference was measured at the level of thehyoid bone. The anteroposterior neck diameter was defined as the distance between thebody of the hyoid bone and the VII spinous process of the cervical vertebra. Neck heightwas measured from the upper to the lower neck borders. Neck width was determined inthe frontal plane at the level of the hyoid bone between the lateral edges of the neck.Statistical analysis of the data was performed using the licensed program RStudio.Results. A morphometric analysis of the average values of the well-known neck parameters,namely its circumference, anterior- posterior diameter, height, and width, was conductedin the perinatal period of ontogenesis. The analysis revealed that these parameters exhibitnon-synchronous growth throughout the studied period of the development, with periodsof intensive and relative growth. A correlation analysis was conducted between allmorphometric parameters of the neck of fetuses and newborns. The results demonstratedthat the correlation coefficients between the values of all paired correlation coefficientswere positive and close to 1 (≥0.90), indicating a strong positive correlation between allstudied parameters. A statistical analysis of the data from the Conover- Iman test indicatesthat the median values of the morphometric parameters of the neck cannot be consideredreliable for the pairs «9 months – 10 months» and «10 months – Newborns». This isjustified by the fact that individual anatomical variability is inherent in each individual,and these periods of the development are critical for the neck area. The constructedstandard anatomical models of the morphometric parameters of the neck will serve asa norm for the subsequent determination of certain morphological deviations, which willthen be used to establish variants of the structure and developmental defects of the neck.Conclusions. 1. During the perinatal period of the development, the well-known parametersof the neck, namely its circumference, anterior- posterior diameter, height and width,increase asynchronously. 2. The average values of the morphometric parameters of the neckcircumference and anterior- posterior diameter during the perinatal period of ontogenesisindicate that one period of accelerated development is evident, occurring between the 7thand 9th month of intrauterine development for the neck circumference and between the 6thand 9th month of development for the anterior- posterior diameter of the neck. Two periods ofaccelerated development are observed for the parameters of neck height and width. For neckheight, these periods are from the 5th to the 7th month of development and from the 8th to the9th month of development. For neck width, the periods are from the 4th to the 5th month ofthe development and from the 7th to the 9th month of intrauterine development. In all otherperiods of development, the morphometric parameters of the neck exhibit a slight increase. 3.Based on the arithmetic mean data of the circumference, anterior- posterior diameter, height,and width of the neck, models for predicting the normative morphometric parameters of fetusesand newborns were constructed. The systematized data on the peculiarities of spatial andtemporal transformations of the morphometric parameters of the neck circumference, anteriorposterior diameter, neck height and width, followed by their construction of mathematicalmodels, will contribute to the individualization of the norm, improvement of early diagnosticmethods and development of new methods of surgical correction of congenital neck defects.

Pigs as Models to Test Cardiovascular Devices.

Pigs as laboratory animals are used in preclinical studies aimed at developing medical devices for cardiac surgery. The anatomy of the cardiovascular system of these animals has been well studied and acknowledged as suitable for use and the testing of new cardiovascular devices developed for humans. However, there are no morphometric characteristics of the aortic root and thoraco-abdominal part of porcine aorta. This can lead to difficulties in experimental surgery and even result in the death of experimental animals due to the mismatch in the size of the implantable devices. Thus, such information is essential to enhance the efficiency of surgical technologies used for eliminating aortic pathologies in their various sections. The purpose of our research is to study the anatomy of the aorta in mini pigs and to assess whether the size, age, and sex of the animals affect the size of the main structures in their aortas. In addition, we attempted to compare the results obtained by transesophageal echocardiography (TEE) and angiography. We studied 28 laboratory mini pigs, dividing them into three groups by body weight (40-70 kg, 71-90 kg, and 90 kg). We did not find any relationship between the external somatometric characteristics of the animals and the size of their aortas. Animals have individual anatomical variability in their cardiovascular systems, which means that they need to be examined in terms of preoperative planning by any available method-echocardiography, angiography, or multispiral computed tomography (CT).

How palatal vault morphology and screw length influence the accuracy of dynamic computer-guided orthodontic miniscrew insertion. A prospective clinical study

ObjectivesThe aim of this study was to evaluate the influence of palatal vault morphology and screw length on the accuracy of miniscrew insertion in dynamic computer-assisted surgery (d-CAS). MethodsTwenty-four subjects were allocated into three groups, according to their palatal vault morphology (Group A: medium; Group B: steep/high; Group C: low/flat) and the length of miniscrew used. For each subject, two miniscrews were inserted using a dynamic navigation system. To assess the accuracy of insertion, a postoperative CBCT was performed, and the pre- and post-operative scans were superimposed. Five variables were evaluated: Entry-3D, Entry-2D, Apex-3D, Apex-vertical and angular deviation. Descriptive statistics, Shapiro-wilk, Kruskal-Wallis and Dunn's tests were used for the statistical analysis. The level of significance was P ≤ 0.05. ResultsThe mean angular deviation values revealed strong discrepancies amongst the groups (Group A:7.11°±5.70°; Group B:13.30°±7.76°; Group C:4.92°±3.15°) and significant differences were found regarding the Apex-3D (P = 0.036) and angular deviations (P = 0.008). A Dunn's test revealed differences in angular deviation between the medium and high/steep palate group (P = 0.004), and between low/flat and high/steep palate group (P = 0.01) but did not confirm any significant difference in the Apex-3D parameter (Group A-B P = 0.10; Group B-C, P = 0.053; Group A-C, P = 1.00). No significant differences were found regarding the length of the miniscrews. ConclusionsPalatal vault morphology is a factor that influences the accuracy of miniscrew insertion in d-CAS. In subjects with steep and high palatal vaults, insertion accuracy is lower when considering the angular deviation value. Miniscrew length does not influence accuracy. Clinical significanceAlthough computer-guided surgery assists the clinician in preventing damage to nearby anatomical structures, individual anatomical variability is a crucial variable. In subjects with a high/steep palate, greater attention should be paid during the planning phase in order to allow for a wide margin from adjacent anatomical structures to achieve better outcomes.

The role of variant anatomy in neurosurgery

Variants of atypical structure and location of anatomical structures always complicate the course of surgical access and admission and are often the causes of surgical errors and complications. This article presents an overview of some features of variant anatomy in areas of interest to neurosurgeons, including those leading to the development of intraoperative problems and postoperative neurological deficits.The main message of the article is not only that neurosurgeons should plan surgery taking into account individual anatomical variability starting with the shape of the skull, but also that in cases of adverse perioperative events, atypical anatomy should be taken into account as an objective risk factor and have a mitigating value in the evaluation of the neurosurgeon’s performance.The aim of this paper is to present and analyse scientific publications on variant anatomy, determining its role in the development of surgical errors and complications in neurosurgery.

432 Ligament Engagement and In-Situ Force During Multiplanar Loading of the Medial Knee Ligaments

OBJECTIVES/GOALS: Load sharing across the arc of knee flexion of the medial knee ligaments (MKLs) is not well understood. The goal of this research is to characterize ligament engagement and in-situ force within the deep and superficial medial collateral ligament (dMCL, sMCL) and the posterior oblique ligament (POL) in response to externally applied multiplanar loads. METHODS/STUDY POPULATION: Ten human cadaveric knees, 5 male and 5 female, age 32±7 (25-42) [mean±SD (range min-max)] years, were mounted to a force sensor and a 6-degree-of-freedom robotic arm. Knee kinematics, before and after serial dissection of the sMCL, dMCL, and POL, were recorded from 0-30 degrees during applied isolated external rotation, valgus angulation, and anterior tibial moments, and the force (Newtons, N) borne by each structure was measured via the principle of superposition. Loads in the dMCL, sMCL, and POL will be compared across each knee and at each flexion angle with paired t-tests and repeated-measures analysis of variance with Tukey post hoc testing. Ten knees will provide >99% power to detect differences of 5N ± 3% at p=0.05, which is considered the threshold for clinically meaningful force differences. RESULTS/ANTICIPATED RESULTS: Our anticipated results include characterization of the means and standard deviations of the in-situ forces within the dMCL, sMCL, and POL in response to externally applied valgus angulation, tibial external rotation, and anterior-directed tibial loading at 0, 15, and 30 degrees of knee flexion. Our statistical analysis will determine if there are clinically meaningful differences (5N ± 3%) in the loads within each ligament at different knee flexion angles and will also provide data regarding differential relative ligament engagement for each applied force scenario, which is an indication of the percentage of contribution that each structure contributes to knee stability during application of forces and torques to the knee. DISCUSSION/SIGNIFICANCE: Data on ligament engagement and in-situ forces will help clinicians better diagnose potentially injured ligaments when they observe pathological knee laxity in an injured patient. Our results will also inform future computer modeling studies on injury mechanisms, individual anatomical variability, and surgical planning.

CRANIOTOPOGRAPHIC FEATURES OF THE TRANSVERSE SINUSES OF THE DURA MATER OF THE BRAIN OF THE CRANIAL VAULT OF MATURE PEOPLE

The goal of our research is the description of craniotopographic features of the transverse sinuses of the dura mater.
 The aim and the methods of research. In order to achieve the goal, a set of methods for morphological studies was developed: macro- and micropreparation of anatomical objects of the brain; cranio– the morphometry of veins, sinuses, and the cervian structures of the cephalic brain; preparation of corrosive (acrylic) ulcerative preparations of veins, sinuses of the dura mater and pervoric lesions of the head; injection technique; variational and statistical analysis of morphometric data; computer-graphic analysis. This study was conducted on 70 preparations of veins and sinuses of the dura mater of the brain.
 Results of the study and their discussion. Considering the above-mentioned facts, we established a craniotopographical projection of the transverse sinuses in relation to generally accepted craniotopographical planes and points. According to the data we have obtained, the venous collectors (transverse sinuses) studied by us have a certain projection analogy on the bones of the cranial vault and the corresponding correlations to the craniometric points, which can be used in medical craniology. In this regard, there is a natural range of individual anatomical variability in the parameters of the dura mater, which are described in people of mature age. The obtained data on the structure, shape, size and position of the venous collectors of the cranial vault (transverse sinuses) can be used in surgical interventions on the cerebrospinal fluid system, including the ventricles and cerebrospinal fluid pathways.
 Transverse sinuses, located on both sides of the skull in the horizontal plane, are of important practical importance from a neurosurgical point of view. In adults, fully formed right and left transverse sinuses are always noted, which perform an important transport function of carrying venous blood from the drain of the sinuses into the sigmoid sinus and internal jugular veins.
 The transverse sinuses of the posterolateral surface are adjacent to the inner surface of the parietal and occipital bones, which explains the frequent damage and injury to the collector in various skull injuries. In addition, these collectors must be taken into account during surgical access to various parts of the brain, including the lateral ventricles.
 Taking into account the above, it is possible to distinguish different areas of the accumulation of veins that flow into the transverse sinuses. The densest location of tributaries, branches and anastomoses is observed in the initial part of the collectors, near the drainage of the sinuses, due to the surface veins of the occipital lobe and the veins of the cerebellar tent. The second place of accumulation of venous vessels is noted in the area of the transition of the transverse sinuses into the sigmoid sinuses, where the superficial temporal and parietal veins are concentrated.
 Conclusions. The obtained results not only complement the known facts, but also more deeply reveal the principles of the craniotopographic structure of the transverse sinuses of the dura mater of the cranial vault of people of mature age.
 On the basis of the actual data obtained, the position is substantiated, according to which a kind of “vascular zone” in the middle part of the transverse sinuses is topographically distinguished, where, in our opinion, it is better to perform surgical interventions in neurosurgical practice.

ANATOMICAL VARIABILITY OF THE SEGMENTS OF THE INFERIOR ALVEOLAR NERVE IN THE PEOPLE OF SECOND PERIOD OF MATURE AND OLDER AGE

To avoid complications of bicortical implantation, great importance is attached to the study of individual morphological features of the mandible and its structures, in particular, the anatomical variability of the inferior alveolar nerve (IAN) and mandibular canal. The purpose of the study was to fi nd out the peculiarities of the structure, topography and individual anatomical variability of the IAN in persons of the second period of maturity and older age. Cone-beam computer tomography of 54 people of both sexes aged 45-65 years with three- dimensional reconstruction, morphometry and statistical analysis was studied. On the basis of our own research on the topographical and anatomical features of the IAN and its syntopy with the mandible, in particular, with the mandibular canal, we propose to distinguish 4 of its divisions: extra- canal – from the place of formation to the entrance to the mandibular canal; intracanal – from the mandibular foramen to the mental foramen; mental – after exiting the mandibular canal; incisive – after the departure of the mental branch. The topographical and anatomical features and anatomical variability of the IAN were studied. In people of the second period of mature and elderly age, anatomical variability of the macroscopic structure and topography of the IAN was established, which manifested itself in high (4.0-11.0 mm) and low (22.0-33.0 mm) levels, relative to the foramen ovale its beginning and form (one or two trunks) of departure from the mandibular nerve. The largest number of nerve connections with other branches of the mandibular nerve is formed by the extracanal section of the IAN: with the auriculo-t emporal nerve (29 cases – 53.7 %), with the lingual nerve (5 cases – 9.26 %), with the nerve of the medial pterygoid muscle (3 observations – 5.56 %) and with the nerve of the lateral pterygoid muscle (2 specimens – 3.7 %). A diff erent level of departure of the nerve to mylohyoid from the extracanal section of the IAN was established: high (5.0-7.0 mm) and low (27.0-31.0 mm). Anatomical variability of the intracanal part of the IAN was manifested by structural variants: a single trunk (43 cases, 79.6 %), rarely – two trunks (11 observations, 20.4 %) and very rarely – the lower dental plexus (6 specimens, 11,11 %). The proximity of the roots of the 7th and 8th teeth to the IAN can be the cause of severe pain in the pathology of these teeth and cause nerve damage during their removal. Nerve connections occur between the right and left incisive nerves, the knowledge of which is an important practical value for performing anesthesia of the front row of teeth. The number of branches to the teeth, interalveolar septa and gingiva from the IAN signifi cantly decreases with age and with a violation of the integrity of the dentition.

FETAL ANATOMY OF THE ARTERIES OF THE DORSUM OF THE HAND

Fetal anatomy of the upper extremity in today’s understanding is a set of morphological methods for studying the structure and topography of the structures of its separate areas in human fetuses from the standpoint of the norm and taking into account the forms of individual anatomical variability. Also, in recent decades, microsurgical anatomy has gained intensive development, in particular the hand, which allows studying the structure and topography of small anatomical structures – blood vessels and nerves, muscle tendons, their layer-by-layer relationship in normal anatomical formation, and pathological deviations depending on the needs of microsurgery.The purpose of the study was to fi nd out the sources of blood supply, topography, and branching areas of the arteries of the back of the hand in human fetuses. The study was conducted on the preparations of 18 human fetuses aged from 4 to 10 months using macromicroscopic preparation, injection of arterial vessels, and morphometry.In human fetuses, the arteries of the back of the hand are arranged in two layers. The surface layer of the arterial vessels of the back of the hand, as a rule, is formed by the radial and anterior interosseous arteries, and (or), less often, by the ulnar or posterior interosseous arteries without the formation of arterial arches or nets. The deep layer of the arteries of the back of the hand mostly forms the back carpal arch and is inseparably connected both with the arteries of the superfi cial layer of the back of the hand and with the palmar arterial arches.The arteries of the deep layer of the back part of the hand are mostly (69.5 % of cases) represented by the back arterial arch: 1) radial-i nterosseous; 2) radial-i nterosseous-ulnar; 3) radial- ulnar; in 25 % of observations – with the posterior carpal arterial network. In 5.5 % of cases, the posterior carpal arch or posterior carpal mesh was absent, and duplication of the deep palmar arterial arch was found. Variability of the sources of formation, the degree of development, and the number of dorsal common digital arteries were revealed in human fetuses.Own dorsal digital arteries, except for the arteries of the thumb, as a rule, reach only the level of the middle phalanx of the fi ngers, and then they become thinner, or end in the periosteum or arterial arch-shaped anastomoses of the fi rst interphalangeal joint, or end in the palmar digital arteries, which provide blood supply to the back surface of the distal parts of the fi ngers of the brush.

A method of evaluation of the shape of the human cerebellum: MRI study

The variability of shape of an organ is one of the manifestations of its individual anatomical variability. Magnetic resonance imaging and other modern neurovisualization methods allow for in vivo determination of morphological characteristics of organs, considering their natural positioning. The aim of this study is to develop a method of evaluation of the shape of the human cerebellum based on the results of MR imaging morphometry. MR images of the brain were obtained from 30 subjects (15 male and 15 female aged between 20 and 40 years) without apparent brain pathology. MRI was performed using a 1.5 T MRI machine (Siemens Magnetom Symphony, Munich, Germany). The width of the cerebellum was determined in axial (Wax) and coronal (Wcor) planes, the length was determined in axial (Lax) and sagittal (Lsag) planes, the height was determined in coronal (Hcor) and sagittal (Hsag) planes. It was observed that the width of the cerebellum is determined almost equally in two different planes, the greater disparity is noted in the measurements of length and the maximum difference in values was found in the measurements of height. A moderate and statistically significant linear relationship was discovered between the variables Wax and Lax (r=0.48; p<0.01), as well as between Wcor and Hcor (r=0.39; p<0.05). Variability in the values of paired linear dimensions measured in a single plane and the absence of a functional relationship between them lead to variability in their ratios, or shape factors (Wax / Lax, Wcor / Hcor, Lsag / Hsag). These shape factors, in turn, influence the shape of intracerebellar structures, primarily the cerebellar nuclei. To evaluate the overall shape of the cerebellum, the following parameters have been proposed, which describe the relationships between one linear dimension of the cerebellum to the other two: relative width of the cerebellum (Wr=(Wax×Wcor) / (Lax×Hcor)), relative length of the cerebellum (Lr=(Lax×Lsag) / (Wax×Hsag)), and relative height of the cerebellum (Hr=(Hcor×Hsag) / (Wcor×Lsag)). Further analysis of these parameters defines which of the linear dimensions has a greater influence on the shape of the cerebellum, determining its structural features, such as the shape of its lobules, the course of its fissures, and the three-dimensional organization of its nuclei, among others. In vivo evaluation of cerebellar shape will facilitate improvements in the diagnosis of cerebellar disorders using MRI and will be valuable in conducting neuromorphological research studies.

Individual anatomical variability of the angular parameters of the parietal bones of the cranial vault in mature person

Annotation. Given the emergence of new modern methods and systems of instrumental research, modern morphology, in particular craniometry, prefers and is aimed at the study of anatomical structures during life. The purpose of our study is to establish the individual anatomical variability of the angular parameters of the parietal bones of the cranial vault of an adult. The morphometric study was conducted on 82 bone specimens and 48 tomograms. To establish the craniotype and divide the material into groups based on it, the main cranial index was calculated, which is determined by the percentage ratio of the width of the skull to its length. Along with this, the angular parameters on the left and right half of the skull vault, at the transition points of the interosseous seams surrounding the parietal bones, were studied. Variational and statistical analysis was performed with the help of Statistica 13.5.0.17 (trial version) and Microsoft Excel corporate package MS 365. It was established that in all cases the frontal angle exceeds the right angle, which is especially characteristic of mature people with a dolichocephalic head shape. In our opinion, this happens under the influence of an increase in the length and height of the cerebral part of the skull and the vault as a whole in dolihocephals. The anteroinferior (sphenoid) angle has characteristic values less than a right angle, namely, in people with a meso- and dolichocephalic head shape, with the exception of people with a brachycephalic shape, in which the transverse dimensions of the skull and its vault are significantly increased. The posterosuperior (occipital) angle has variable values that exceed an angle of 90°, especially in round-headed people (brachycephals). With brachycephaly, the range of the posteroinferior (mastoid) angle is increased to 150°-151°in men and 138°-146°in women with a gradual decrease in meso- and dolichocephaly. The conducted research showed that the corners of the parietal bone have a certain dependence on the shape and size of the cerebral part of the skull. The obtained results complement the existing data on the angular parameters of the parietal bones of the skull vault and can serve as a reference point and basis for further research with an in-depth study of the intravital morphology of these structures using modern instrumental research methods.

A method for chronic and semi-chronic microelectrode array implantation in deep brain structures using image guided neuronavigation

BackgroundAccurate targeting of brain structures for in-vivo electrophysiological recordings is essential for basic as well as clinical neuroscience research. Although methodologies for precise targeting and recording from the cortical surface are abundant, such protocols are scarce for deep brain structures. New methodWe have incorporated stable fiducial markers within a custom cranial cap for improved image-guided neuronavigation targeting of subcortical structures in macaque monkeys. Anchor bolt chambers allowed for a minimally invasive entrance into the brain for chronic recordings. A 3D-printed microdrive allowed for semi-chronic applications. ResultsWe achieved an average Euclidean targeting error of 1.6 mm and a radial error of 1.2 mm over three implantations in two animals. Chronic and semi-chronic implantations allowed for recording of extracellular neuronal activity, with single-neuron activity examples shown from one macaque monkey. Comparison with existing method(s)Traditional stereotactic methods ignore individual anatomical variability. Our targeting approach allows for a flexible, subject-specific surgical plan with targeting errors lower than what is reported in humans, and equal to or lower than animal models using similar methods. Utilizing an anchor bolt as a chamber reduced the craniotomy size needed for electrode implantation, compared to conventional large access chambers which are prone to infection. Installation of an in-house, 3D-printed, screw-to-mount mechanical microdrive is in contrast to existing semi-chronic methods requiring fabrication, assembly, and installation of complex parts. ConclusionsLeveraging commercially available tools for implantation, our protocol decreases the risk of infection from open craniotomies, and improves the accuracy of chronic electrode implantations targeting deep brain structures in large animal models.

Individual-typological assessment of the body fat component of the examined children and youth

Background. Individual anatomical variability in the human body shape can be characterized by its proportions, which serve as the main components of assessing the type of human constitution.
 Aim. Establish individual typological features of the age-related changes in the fat component of the examined children, adolescents and youth.
 Material and methods. 409 residents of the Smolensk region aged 420 years were examined: 212 males and 197 females. The cohort was divided according to the International Age Periodization 1965. Studies of the longitudinal-transverse type lasted for 10 years (20102020). The research methods included anthropometry, somatodiagnostics, determination of the biological development variant. To determine the fat component, the thickness of the skin-fat folds was measured, the calculation was made according to the formulas of Ya. Mateyko. The analyzed data had a normal distribution (ShapiroWilk test). The hypothesis of statistical significance of differences was tested using Student's t-test.
 Results. Assessment of age-related changes in the body fat component of the subjects showed its continuous increase from 4 to 20 years. In female subjects it was higher, the significance of differences was established from the age of 12 (p 0.05). The fat component had a high and moderate degree of correlation with body height and weight (r=0.5330.753 and r=0.5300.833), skin-fat folds (r=0.5010.941) and body circumference (r=0.5030.790). Significant differences were established between the extreme variants of biological development (isochronic approach) (t=2.3052.604; р 0.05). In the examined males, the difference was 1012%, females 2530%. Somatotypological assessment (isosome approach) showed significant differences (t=3.4626.781; p 0.001) in the severity of fat mass in the subjects of both sexes of macrosomal and microsomal types.
 Conclusion. The conducted studies have confirmed the presence of high individualization of the fat components growth processes of male and female subjects of various somatic types and biological development variants.

TOPOGRAPHIC AND ANATOMICAL RELATIONSHIPS OF INTRAMUSCULAR ARTERIES AND NERVES IN THE SHOULDER REGION OF HUMAN FETUSES

In modern surgical practice, there is a growing need to improve techniques of operative interventions. Despite advancements in diagnosis and treatment, combined shoulder injuries remain a pressing problem. In the past, surgical intervention for combined trauma primarily focused on saving the patient's life. However, today it is essential not only to preserve life but also to restore the function of the injured structures. Humerus fractures are observed in 27.9% of polytrauma cases, significantly complicating urgent diagnostic and treatment procedures and worsening the patient's condition. A comprehensive study of the topographical and anatomical relationships of intramuscular arteries and nerves at the shoulder level can facilitate the selection of optimal surgical approaches, prevent iatrogenic damage, and contribute to the patient's rapid rehabilitation.
 The objective of this study was to identify the distribution patterns of arteries and nerves at different levels of the shoulder in human foetuses.
 Materials and Methods. The study involved the examination of upper limb preparations from 48 human foetuses, ranging from 81.0 to 370.0 mm in parietal-caudal length without external signs of anatomical deviations or anomalies in the development of the skeletal and muscular structures of the upper limbs. Macromicroscopic dissection, vessel injection, and morphometry techniques were employed.
 Results and Discussion. In human foetuses, the upper and middle thirds of the shoulder were found to have the highest concentration of intramuscular arteries and nerves. The entry points of arteries and nerves, their topography and branching patterns within the shoulder muscles did not always align. Arterial branches generally entered the muscles at slightly more distal locations than the nerve trunks, following the shortest path to reach the muscles.
 The levels at which arteries and nerves start branching to supply and innervate the muscles of the anterior and posterior shoulder groups, vary in human foetuses. This variation depends on the individual anatomical variability of the major vascular and nerve trunks.
 Conclusion: The levels of arterial and nerve abduction are related to the topographic and anatomical features of a particular shoulder muscle. Considering the topography of intramuscular arteries and nerves, it is advisable to perform incisions along the direction of muscle bundles, particularly near the lower border of the neurovascular unit of the brachial biceps. This approach can offer higher clinical and surgical effectiveness.

Patient-Individualized Identification of Medial Patellofemoral Ligament Attachment Site to Femur Using "CLASS" MRI Sequences.

Malposition of the femoral tunnel during medial patellofemoral ligament (MPFL) reconstruction may increase the risk of recurrence of patellar dislocation due to isometric changes during flexion and extension. Different methods have been described to identify the MPFL isometric point using fluoroscopy. However, femoral tunnel malposition was found to be the cause of 38.1% of revisions due to patellar redislocation. This high rate of malposition has raised the question of individual anatomical variability. Magnetic resonance imaging (MRI) was performed on 80 native knees using the CLASS (MRI-generated Compressed Lateral and anteroposterior Anatomical Systematic Sequence) algorithm to identify the femoral MPFL insertion. The insertions were identified on the MRI views by 2 senior orthopaedic surgeons in order to assess the reliability and reproducibility of the method. The distribution of the MPFL insertion locations was then described in a 2-plane coordinate system and compared with MPFL insertion locations identified with other methods in previously published studies. The CLASS MPFL footprint was located 0.83 mm anterior to the posterior cortex (line 1) and 3.66 mm proximal to the Blumensaat line (line 2). Analysis demonstrated 0.90 and 0.89 reproducibility and 0.89 and 0.80 reliability of the CLASS method to identify the anatomical femoral MPFL insertion point. The distribution did not correlate with previously published data obtained with other methods. The definitions of the MPFL insertion point in the studies by Schöttle et al. and Fujino et al. most closely approximated the CLASS location in relation to the posterior femoral cortex, but there were significant differences between the CLASS method and all 4 previously published methods in relation to the proximal-distal location. When we averaged the distances from line 1 and line 2, the method that came closest to the CLASS method was that of Stephen et al., followed by the method of Schöttle et al. The CLASS algorithm is a reliable and reproducible method to identify the MPFL femoral insertion from MRI views. Measurement using the CLASS algorithm shows substantial individual anatomical variation that may not be adequately captured with existing measurement methods. While further research must target translation of this method to clinical use, we believe that this method has the potential to create a safe template for sagittal fluoroscopic identification of the femoral tunnel during MPFL surgical reconstruction. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

ANALYSIS OF UPPER RESPIRATORY TRACT SEGMENTATION FEATURES TO DETERMINE NASAL CONDUCTANCE

The paper examines the features of segmentation of the upper respiratory tract to determine nasal air conduction. 2D and 3D illustrations of the segmentation process and the obtained results are given. When forming an analytical model of the aerodynamics of the nasal cavity, the main indicator that characterizes the configuration of the nasal canal is the equivalent diameter, which is determined at each intersection of the nasal cavity. It is calculated based on the area and perimeter of the corresponding section of the nasal canal. When segmenting the nasal cavity, it is first necessary to eliminate air structures that do not affect the aerodynamics of the upper respiratory tract - these are, first of all, intact spaces of the paranasal sinuses, in which diffuse air exchange prevails. In the automatic mode, this is possible by performing the elimination of unconnected isolated areas and finding the difference coefficients of the areas connected by confluences with the nasal canal in the next step. High coefficients of difference of sections between intersections will indicate the presence of separated areas and contribute to their elimination. The complex configuration and high individual variability of the structures of the nasal cavity does not allow segmentation to be fully automated, but this approach contributes to the absence of interactive correction in 80% of tomographic datasets. The proposed method, which takes into account the intensity of the image elements close to the contour ones, allows to reduce the averaging error from tomographic reconstruction up to 2 times due to artificial sub-resolution. The perspective of the work is the development of methods for fully automatic segmentation of the structures of the nasal cavity, taking into account the individual anatomical variability of the upper respiratory tract.

Craniometric parameters of the spatial position of the supraorbital, infraorbital and mental foramens depending on the facial index of the skull of a mature person

Due to increase of various operative interventions in the facial region of a mature person, it is expedient to study in detail the spatial position of the foramens of the facial part of the skull. Knowing the exact position of the foramens will help doctors during operations and minimally invasive interventions to prevent damage to the vascular and nerve bundles that pass through these foramens. The purpose of our work is to determine the craniometric characteristics and spatial position of the supraorbital (SF), infraorbital (IF) and mental (MF) foramen, depending on the type of structure of the facial part of the skull. The study was performed on 52 bone specimens of skulls and 60 CT images of adults without damage to the bone structures of the front part of the skull. Statistical methods were used to analyze the obtained measurement results in our research, which was carried out with the help of the Microsoft Excel 2010© licensed program package and with the help of the "STATISTYCA" program. When determining the position of the foramens of the facial part of the skull, first of all, we determined the individual anatomical variability of the facial part of the skull, which has the following extreme types: europrosopics (broad-faced), mesoprosopics (medium-faced), leptoprosopics (long-faced). By dividing the skulls according to the facial index, we determined the width and height of SF, IF and MF, and it was found that their diameter does not depend on the extreme types of the facial part of the skull. With the help of corresponding program, the average, lateral and line between the zy-zy points were constructed on the CT images of the 3-D models of the skulls to determine the position of SF, IF, MF relative to these lines depending on the facial index. The average values obtained were analyzed and it was established that the distance from SF, IF and MF to the median and lateral lines has larger values in europrosopics, intermediate values have mesoprosopics, the smallest results were determined in leptoprosopics. The results of the study of the distances from the above-mentioned foramens to the zy-zy line indicate an increase in their values in leptoprosopics, as opposed to europrosopics. The data we obtained confirm the dependence of the spatial position of the foramens on the type of structure of the facial part of the skull. The obtained data will supplement the craniotopographical characteristics of SF, IF and MF, and also provide a basis for further research of their position depending on the facial index.

A NEW CONCEPT OF ZONAL AND SEGMENTAL STRUCTURE OF THE HUMAN KIDNEY

To date, there is no single point of view on the lobar, zonal and segmental structure of the arterial tree of the kidney. There is no generally accepted approach in determining the signs by which the kidney is divided into lobes and/or segments. There is still a discussion regarding the division of the renal artery to daughter branches. The aim of the study was to establish variants of individual anatomical variability of the intra-organ arterial bed of the kidney, taking into account zonal and segmental topography. 116 corrosive preparations of the arterial system of the human kidney were studied. In 3D projections, the number of arterial vessels in the hilum of the kidney, topographic and anatomical features of the trunks of the renal arteries in the hilum of the kidney, variants of division of the renal arteries, zones of local blood supply to areas of the substance of the kidney, depending on the variants of division of the renal artery into branches of the 2nd and 3rd orders. The study was carried out using digital visualization methods, digital image processing and appropriate software. As a result, it was found that the renal artery can be divided into two (two-zonal system of blood supply to the kidney) and three (three-zone system of blood supply to the kidney) zonal arteries. In the case of a bizonal system, the renal artery divides into ventral and dorsal branches (54,2% of cases), as well as superior polar and inferior polar zonal branches (15,5% of cases). In the case of a three-zone system, the following options for the division of the renal artery have been established. The first option - on the upper polar, ventral and dorsal zonal branches (in 13,3% of cases); 2nd option - on the ventral, dorsal and lower polar zonal branches (in 9,4% of cases); 3rd variant - on two ventral and one dorsal zonal branches (in 5,1% of cases) and 4th variant on the superior pole, central and inferior pole zonal arteries (in 2,5% of cases). The results of the study convincingly indicate the need to revise the widespread idea of ​​the five-segment structure of the human kidney.

Метод макромікроскопічного препарування для встановлення фетальної анатомічної мінливості структур пахвової ділянки

The purpose of the study was to determine a more sophisticated method of the most rational sequence of actions of dissection of the fascia, muscles, vessels and nerves of the axillary cavity in human fetuses in order to obtain standard results suitable for comparison in the age aspect. Materials and methods. The study of fetal anatomy of the structures of the axillary area was performed on 25 preparations of 4-10-month human fetuses of 81.0-375.0 mm parietal-coccygeal length using macromicroscopic dissection. Results and discussion. The axillary area is characterized by age and individual anatomical variability of the muscles that form its walls, fascia and cellular spaces, as well as vascular and nervous formations that pass in it, which is a common cause of complications during surgery. To study the fetal anatomical variability of the components of the axillary area, the algorithm of anatomical dissection of fascia, muscles, lymph nodes, blood vessels and nerves of the axilla in the human fetus is of priority importance. Adherence to the sequence of actions during the anatomical dissection of the components of the axillary area provides not only high representativeness and scientific value of the results, but also the rational use of biological material. The delta-thoracic sulcus fossa and the beak-shoulder muscle can be used to determine the topography and projection of the vascular nerve trunks of the axillary area. The obtained data on the variant anatomy of the pectoralis major and anterior dentary muscles, as well as the widest back muscle are consistent with the studies of individual authors. The study of the structure and topography of fascia, muscles, lymph nodes, nerves, arteries and veins of the axillary fossa in human fetuses from a macroscopic point of view in modern anatomy remains relevant and promising because micro- and ultramicroscopic anatomy does not provide a comprehensive answer and does not fully reveal the versatility of fetal anatomical variability, in the study of which the algorithm of anatomical dissection of the constituent formations of the axillary area becomes a priority. Conclusion. The projected and tested method of dissection of fascial-muscular and vascular-nervous formations of the axillary area in human fetuses provides a standard for obtaining data on their typical, individual and age anatomical variability. The order of actions used during the dissection of the muscles that form the walls of the axilla, fascial-cellular formations, vessels and nerves, as well as axillary lymph nodes in human fetuses preserves the naturalness of the appearance and relationships between the structures of the object of study. Macromicroscopic preparation revealed fetal anatomical variability of muscles, arterial and venous vessels and axillary nerves

Individual anatomical variability of dental arches in the period of mixed dentition with optimal occlusal ratios

Based on the results of a biometric study of plaster models of the jaws obtained in 84 children in the period of mixed dentition (8–12 years old) with a neutral location of the first permanent molars and optimal incisal overlap corresponding to the optimal functional occlusion of this age category, the main linear and angular parameters of the dental arches were determined with taking into account the trusive position of the incisors. Patients, taking into account the size of the inter-incisal angle, were divided into three groups. The first group (n=33) consisted of children with a mesotrusion position of the incisors (the value of the inter-incisor angle was 125–140°), the second group (n=27) consisted of children whose incisors were located protrusive (the value of the inter-incisor angle was less than 125°), the third group (n=24) – children with retrusion position of the incisors (the value of the inter-incisal angle is more than 140°). It has been established that in the period of mixed dentition, the main linear morphometric parameters of the dental arches are determined by the trusive types of the dental system and the vestibular-lingual inclination of the incisors. A diagnostically significant characteristic of the conjugation of the shape and size of the dental arches in the period of mixed dentition is the dental-diagonal coefficient, as the ratio of the length of the dental arch to the total component of the incisor-molar diagonals, the value of which for all types of dental systems is: for the upper jaw – 1.06 ± 0 .01; for the lower jaw – 1.09±0.01. It has been proven that in the period of mixed dentition the value of the incisal angle of the pentagon formed by the incisal diagonal and the width between the incisors is the smallest in children with protrusive incisors, while the parameters of the canine angle of the pentagon formed by the canine diagonal and the intercanine width are the largest in children with retrusion position of the incisors.

VARIABILITY OF TRACHEAL BIFURCATION ACCORDING TO MAGNETIC RESONANCE IMAGING

Modern methods of radiological diagnostics allow to visualize in life the structural and topographic peculiarities of the structure of the human body, signifi cantly expanding the range of individual anatomical variability of its individual parts and organs. Detailed study of tracheal bifurcation and structure and topography of the main bronchi by in vivo imaging using computed tomography and magnetic resonance imaging attracts the attention of researchers, as it allows to identify and describe variation series and extreme forms of individual norms of the studied structures. The aim. Elucidation of possible variants of tracheal bifurcation and topography of the main bronchi in individuals of mature age according to magnetic resonance imaging. In the course of the work, an analysis of 18 series of anonymized magnetic resonance computed tomography of the thoracic cavity of the individuals of mature age, performed on a Siemens Avanto 1.5T, followed by processing the results with the MicroDicom operating program in 3D-COR mode. In the study of tomograms, it was determined the magnitude of the bifurcation angle of the trachea and the angles of branching of the right and left main bronchi. In the processed randomized sample, the value of the bifurcation angle of the trachea was 79±2.16°. The angle of branching of the left main bronchus was 133.14±3.52 °, and the right main bronchus – 147.72±3.39°. With the general tendency to the predominance of the right main bronchus, the analysis of a series of tomograms showed that only in 13 people (72.2%) right main bronchus was an extension of the trachea and the angle of its branching was greater than the left main bronchial angle. In 3 persons (16.7%) the values of the angles of branching of the right and left main bronchi were almost the same, and in 2 persons (11.1%) the angle of branching of the left main bronchus from the trachea was greater than the angle of branching of the right main bronchus. Identifi ed variants of bifurcation of the trachea and angles of branching of the main bronchi can be considered as variants of the individual anatomical norm of this area.