Overlapping stimulation of subthalamic nucleus and dentato-rubro-thalamic tract in Parkinson's disease after deep brain stimulation.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) reduces tremor, rigidity, and akinesia. According to the literature, the dentato-rubro-thalamic tract (DRTt) is verified target for DBS in essential tremor; however, its role in the treatment of Parkinson's disease is only vaguely described. The aim of our study was to identify the relationship between symptom alleviation in PD patients and the distance of the DBS electrode electric field (EF) to the DRTt. METHODS: A single-center retrospective analysis of patients (N = 30) with idiopathic Parkinson's disease (PD) who underwent DBS between November 2018 and January 2020 was performed. DRTt and STN were visualized using diffusion-weighted imaging (DWI) and tractography protocol of magnetic resonance (MR). The EF was calculated and compared with STN and course of DRTt. Evaluation of patients before and after surgery was performed with use of UPDRS-III scale. The association between distance from EF to DRTt and clinical outcomes was examined. To confirm the anatomical variation between DRTt and STN observed in tractography, white matter dissection was performed with the Klingler technique on ten human brains. RESULTS: Patients with EF overlapping STN and DRTt benefited from significant motor symptoms improvement. Anatomical findings confirmed the presence of population differences in variability of the DRTt course and were consistent with the DRTt visualized by MR. CONCLUSIONS: DRTt proximity to STN, the main target in PD DBS surgery, confirmed by DWI with tractography protocol of MR combined with proper predefined stimulation parameters may improve efficacy of DBS-STN.

Anatomy and morphology of iliolumbar ligament.

PURPOSE: To address limited amount of available data and contradictory statements in published works 60 Iliolumbar ligaments extracted from 30 cadavers were examined to describe their insertions and morphology. METHODS: The ligaments were removed during the standard autopsy procedures with a use of an oscillating saw, a chisel and a scalpel. The specimens were photographed before the extraction and measured alongside their anterior margin. Next, they were preserved in formaldehyde, stripped of other soft tissues and then examined, photographed and described. RESULTS: The mean length of the ligaments was 31.7 mm. 44 specimens were described as single-banded, 13 as double-banded and 3 as other. In 24 cases costal process of LV has been fixed to the iliac plate by short ligamentous bands. In 38 cases there was a thick fibrous membrane connected to the ligament. No legitimate insertions on LIV vertebra were observed. CONCLUSIONS: Typical iliolumbar ligament consists of a single ligamentous band. Most common variability of the ligament consist of two bands. In approximately 40% of cases the costal process of LV can be additionally stabilized to the iliac plate by short, strong ligamentous bands. In 63% of cases a connection between the iliolumbar ligament and a fibrous membrane placed in the frontal plane, superiorly to the ligament, has been observed. There seems to be no convincing proof of existence of the insertion of the iliolumbar ligament on the LIV vertebra.

Standard clinical computed tomography fails to precisely visualise presence, course and branching points of deep cerebral perforators.

BACKGROUND: Standard computed tomography (CT) images have earned a well-established position in neuroimaging. Despite that, CT is somehow limited by its resolution, which does not enable to distinctively visualise structures smaller than 300 µm in diameter. Perforating arteries, most of which measure 100-400 µm in diameter, supply important subcortical structures (thalamus, basal ganglia, internal capsule). Consequently, pathologies affecting these vessels (e.g. lacunar strokes) can have a devastating clinical outcome. The aim of our study was to assess standard CT's ability to visualise perforators and compare it with microscopic and micro-CT pictures. MATERIALS AND METHODS: We have obtained 6 brainstem and 17 basal ganglia specimens. We infused them with barium sulphate contrast medium administered into either vertebral or internal cerebral artery. After that, the specimens were fixed in formalin and subsequently a series of CT, micro-CT and microscopic examinations were performed. RESULTS: The median number of visualised perforators in brainstem and basal ganglia specimens was 8 and 3, respectively for CT and 18 and 7 for micro-CT (p < 0.05). Standard CT failed to clearly visualise branching points and vessels smaller than 0.25-0.5 mm (1-2 voxels) in diameter. Parallel vessels, like lenticulostriate arteries could not be differentiated in standard CT due to their proximity being smaller that the resolution. CONCLUSIONS: Basing on our results, we infer that CT is a poor modality for imaging of the perforators, presenting both quantitative and qualitative flaws in contrast with micro-CT.

A fully capable pianist with a congenital bilateral agenesis of extensor pollicis brevis muscle.

A 28-year-old male musical student has been presented with visible inability of active abduction and extension of the thumbs in both hands beyond the neutral position. The student has not been previously diagnosed and claimed no history of trauma or surgical procedures in the area of hands and no family history of such disabilities. The student remained capable of playing on keyboard instruments on high level due to compensation by hyperextension of the interphalangeal joint of both thumbs and showed no increased frequency of the injuries or playing-related disorders. The ultrasound and magnetic resonance imaging showed complete bilateral agenesis of extensor pollicis brevis muscles and was classified as isolated congenital clasped thumb syndrome. Due to the age of the student and the agenesis of the muscles the conservative treatment was deemed inadequate and due to high functionality of the student as a musician and unforeseeable results it might have on a musician's career, surgical treatment has been disadvised.

Course variability of the atlantic (V3) segment of vertebral artery: anatomical study with clinical implications.

BACKGROUND: The atlantic segment of vertebral artery (V3) located at the centre of the cranio-vertebral junction is known for its variability and asymmetry, and is either the target or on the way of numerous procedures in this region. The aim of the study was to visualise variability of V3 segment. MATERIALS AND METHODS: The V3 segment was studied in 49 specimens of the suboccipital region injected with coloured gelatine. Direct measurements were performed and probabilistic maps were created using digital photography. RESULTS: The V3 segment has wavy course with possible lateral and significant postero-inferior expansions. In relation to the foramen transversarium the V3 reached up to 5 mm laterally, 23 mm posteriorly, 27 mm medially and up to 11 mm downward. Looking from the medial aspect the course of the V3 is less predictable compared to the lateral approach. Linear measurements and probabilistic maps revealed significant variability and large range of variation. There were 11 cases of V3 tortuosity found in studied material. CONCLUSIONS: The complex and variable spatial conformation of V3 makes individual diagnostic and preoperative approach necessary.

Menisco-fibular ligament - an overview: cadaveric dissection, clinical and magnetic resonance imaging diagnosis, arthroscopic visualisation and treatment.

BACKGROUND: Injury to the menisco-fibular ligament (MFiL) is not commonly recognised. The anatomy of the lateral meniscus is complex and structure-function relationships are only partly understood. The purpose of the present study was to evaluate the MFiL, an anatomic structure rarely discussed that stabilises the lateral meniscus at the level of the hiatus popliteus and may have a crucial role in pathology of lateral meniscus injury. MATERIALS AND METHODS: The MFiL was dissected from its attachment at the lateral meniscus to its insertion on fibular head in 12 human normal cadaver knees. The dimensions were determined and its anatomic position visualised throughout a 90° range of motion. Findings were documented on digital photographs and on video. Results were compared against the magnetic resonance imaging (MRI) appearance of the injured MFiL in 20 patients. Concomitant knee injuries in those patients were also analysed to determine the most frequent pattern of injuries. RESULTS: The normal MFiL showed an inverted trapezoid-shape with a mean width proximally of 13 mm, mean width distally of 8.5 mm and a mean length of 18.4 mm. MRI visualisation of the ligament was possible even in regular sequences; however, additional radial plane sequences were also used. Arthroscopic visualisation and manipulation was optimal when the camera was inserted into the postero-lateral gutter with full knee extension. CONCLUSIONS: The MFiL stabilises the postero-lateral knee in concert with the menisco-femoral ligaments. Injury to the MFiL can be a cause of chronic postero-lateral pain syndrome with associated instability. Further anatomical and biomechanical studies are needed in order to fully evaluate its importance.

Morphology of sesamoid bones in keyboard musicians.

BACKGROUND: The sesamoid bones are small, usually oval bone structures often found in joints and under the tendons. Although their precise function is not fully understood, it is agreed upon that they protect the joints and make movements faster and less energy consuming. Sesamoid bones are found in hands, especially around first, second and fifth metacarpophalangeal joint and the interphalangeal joint of the thumb. MATERIALS AND METHODS: This study compares a group of 32 young musicians to 30 non-musicians of similar age and posture. The hands of the subjects were examined by ultrasound imaging for the presence of sesamoid bones. The results were noted and observed sesamoids were measured. RESULTS: The results seem to prove that although there are no difference in the amount or the location of the sesamoid bones between the musicians and the non-musicians, there is statistically significant tendency for the musicians to have bigger sum of the sesamoid's volume per hand (Fisher's test p-value = 0.034 < 0.05). CONCLUSIONS: There was also observed an unusually shaped "Bactrian" sesamoid bone at the interphalangeal joint of the thumb in 8 cases in the musicians' group and 1 case in the control group. All participants with the aforementioned structure were female.

Diversity of coronary arterial tree in laboratory mice.

BACKGROUND: Research on the development and topography of mouse coronary arteries has been conducted for many years. Patterns of the course of these vessels have been described in various mouse strains. Our research focused on hearts of MIZZ mice. MATERIALS AND METHODS: We visualised the coronary artery system by means of latex dye perfusion via the aorta. The injected latex did not reach the capillary vessel system. RESULTS: The heart of MIZZ mice is supplied with blood by two main coronary arteries: the right and the left one. They deliver blood to the right and left part of the heart, respectively. The right coronary artery arises from the right sinus of the aorta and the left coronary artery from the left sinus. The interventricular septum is usually supplied by the septal artery, which is the main branch of the right coronary artery. All arteries of the coronary system run intramurally. The number of branches and the location of their ostia differed among the examined individuals. CONCLUSIONS: Detailed information about the normal topography of coronary arteries, the number and course of their branches, as well as the area of the heart which is vascularised by these vessels constitutes the basic knowledge necessary to conduct further experiments.

Morphology and morphometry of the semitendinosus distal tendon in adults and foetuses.

BACKGROUND: The distal tendon of the semitendinosus is often used as a graft in orthopedic reconstructive surgery. Knowledge of the exact morphology of this tendon, and also the ability to predict its morphometric data are certainly helpful when planning the procedure of surgery. Comparison of the semitendinosus distal tendon anatomy in adults and foetuses may be scientifically relevant. There are no scientific reports on this tendon anatomy in foetuses. MATERIALS AND METHODS: Seventy semitendinosus muscles from cadavers were obtained using standard dissection techniques (50 muscles were obtained from adults and 20 from foetuses). Moreover, ultrasound examinations of 20 muscles were performed in living individuals. RESULTS: Two main parts of the distal tendon were distinguished - the external part not covered with muscle fibres and the internal part, which is partially or entirely hidden within the muscle belly (venter). The average length of the distal tendon was 32.34 cm, while the average lengths of the external and internal parts were 9.65 cm and 12.59 cm, respectively. The external part was solid and cylindrical. The internal part was flat and rolled like a trough, thus making the tendon a poor transplant material. Similarly, the distal tendon in foetuses consisted of two parts, including the external and internal part. CONCLUSIONS: The proportions between the lengths of different muscle parts were very similar in adults and foetuses.

The sonographic morphology of musculus palmaris longus in humans.

BACKGROUND: The aim of this work was to describe morphology and morphometry of musculus palmaris longus and compare the outcome of Shaeffer's test with ultrasound imaging. MATERIALS AND METHODS: Forty forearms of 20 healthy volunteers (11 females, 9 males) were tested by Shaeffer's test and ultrasound imaging. Anthropological measurements of the forearm and ultrasound guided measurements of musculus palmaris longus were taken. The outcome was tested for statistical significance by Fisher's test. RESULTS: The examination revealed agenesis of palmaris longus in 6 cases, as well as 6 muscles showing quality variations. The Shaeffer's test gave 4 false-negative results. 28 muscles were described as spindle-shaped and 8 as pennated or bipennated. However, all the spindle-shaped muscles demonstrated a tendon going inside of the muscle's belly ranging from 2 cm to 11.5 cm. The relation between the circumference of the forearm right below the elbow (mean: 15.38 cm, SD: 1.83 cm) and the approximated volume of the palmaris longus muscle's belly (mean: 4.72 cm3, SD: 1.57 cm3) proved to be statistically significant (Fisher's test p-value < 0.05). CONCLUSIONS: Uncommon morphological variations have been shown. Spindle-shaped muscles have proved to have their tendons continued inside them. Palmaris longus muscle's belly has proved to take significant amount of volume within the proximal forearm. Shaeffer's test has shown to have 10% false-negative ratio.

Anatomy and morphometry of the distal gracilis muscle tendon in adults and foetuses.

Ten human gracilis muscles obtained from adults and ten gracilis muscles collected from human foetuses between the 15th and 21st week of gestation were examined. The results of this preparatory study show that the gracilis muscle in adults is narrow and long - 482 mm on average. The distal tendon of gracilis muscle is long, 294 mm on average. It can be divided into two sections - external part, outside the muscle belly, and internal, intramuscular, part. The latter one is partially covered by muscle fibres and some of it is completely hidden inside the muscle belly, which is on average 76 mm long. Presence of an intramuscular part of the distal tendon was also demonstrated in the foetal material. Moreover, very strong correlations between particular muscle lengths were noted in foetuses. (Folia Morphol 2018; 77, 1: 138-143).

Stroke Bricks - spatial brain regions to assess ischaemic stroke localisation.

Computer-aided analysis of non-contrast computed tomography (NCCT) images for rapid diagnosis of ischaemic stroke is based on the augmented visualisation of evolving ischaemic lesions. Computerised support of NCCT often leads to overinterpretation of ischaemic areas, thus it is of great interest to provide neurologically verified regions in order to improve accuracy of subsequent radiological assessment. We propose Stroke Bricks (StBr) as an arbitrary spatial division of brain tissue into the regions associated with specific clinical symptoms of ischaemic stroke. Neurological stroke deficit is formally translated into respective areas of possible ischaemic lesions. StBr were designed according to formalised mapping of neurological symptoms and were attributed to the uniquely defined areas of impaired blood supply. StBr concept may be useful for an integrated radiological CT-based assessment of suspected stroke cases or can be included into computer-aided tools to optimise the evaluation of stroke site and its extent. These data in turn are appropriable for further diagnosis, predicting the therapeutic outcome as well as for patients' qualification for an appropriate form of reperfusion therapy. The usefulness of StBr was illustrated in the case studies.

Anatomy of the long peroneal muscle of the leg.

BACKGROUND: The aim of the work was to perform a morphometric analysis of the long peroneal muscle (LPM) of the leg and explore the relationship between muscle belly and tendon. MATERIALS AND METHODS: Ten lower limbs (8 right and 2 left) were fixed in formaldehyde and dissected using standard technique. The LPM was exposed from the proximal attachment to the top of a lateral malleolus. RESULTS: The tendon was subsequently freed and various measurements were taken. The tendon of the LPM enters deep into the muscle belly. Muscle fibres surround the tendon and descend as far down as 4 cm above the lateral malleolus. Muscle fibres insert mainly along posterior border of the tendon and on its medial surface, leaving lateral surface only partly covered. CONCLUSIONS: The LPM contains a long intramuscular segment of the tendon and area of the musculotendinous junction varies along the LPM. It makes the idea of uniform pennation pattern of the LPM unlikely.

Human skull translucency: post mortem studies.

Measurements of optical translucency of human skulls were carried out. An incandescent light source and a CCD camera were used to measure the distribution of light transmitted through the skull in 10 subjects post-mortem. We noticed that intra-individual differences in optical translucency may be up to 100 times but inter-individual translucency differences across the skull reach 105 times. Based on the measurement results, a "theoretical" experiment was simulated. Monte-Carlo calculations were used in order to evaluate the influence of the differences in optical translucency of the skull on results of NIRS measurements. In these calculations a functional stimulation was done, in which the oxyhemoglobin and deoxyhemoglobin concentrations in the brain cortex change by 5µM and -5µM respectively. The maximal discrepancies between assumed hemoglobin concentration changes and hemoglobin concentration changes estimated with Monte-Carlo simulation may reach 50% depending of the translucency of the skull.

The anatomy of the anterior cruciate ligament and its relevance to the technique of reconstruction.

Anterior cruciate ligament (ACL) reconstruction is commonly performed and has been for many years. Despite this, the technical details related to ACL anatomy, such as tunnel placement, are still a topic for debate. In this paper, we introduce the flat ribbon concept of the anatomy of the ACL, and its relevance to clinical practice. Cite this article: Bone Joint J 2016;98-B:1020-6.

Uncommon branching pattern of the hepatic arteries in a living donor: a case report and brief literature review.

Numerous variations of the hepatic arteries are common in surgical patients. We present a 35-year-old woman who was admitted to our department in order to assess possibility of becoming living donor. Preoperative computed tomography scan revealed anomalous branching pattern of the hepatic arteries. In this case right posterior sectoral artery has been given off by the greater pancreatic artery, left hepatic artery has been replaced by the artery arising from the left gastric artery and double segment 4 branches have been observed. To the best of our knowledge, this pattern has not been described in the literature, yet.

Anatomy of sartorius muscle.

A sartorius muscle is the longest muscle of the human system. It runs over 2 joints- hip and knee joints. In the study 10 sartorius muscles were examined. They were dissected free of lower human limbs. Dimensions of limbs which these muscles come from and dimensions of the muscles and their component parts were examined. The attention was paid mainly to parts of tendon located inside the muscle belly. The results show that they are either of a comparable length (distal tendon) or several times longer (proximal tendon) than visible parts located outside of the muscle. Moreover, a complex structure of the distal tendon which includes 2 tracts of different places of insertion was stated. Inferior tract inserted in the same place as muscle tendons: semitendinosus and gracilis. The superior tract inserted transversely against the former one. The tendon of the sartorius muscle forms additionally an aponeurosis whose fibres enter into the deep fascia of crus. The muscle belly is characterised with various width on different levels of its length. In half of casess word-like distal segment of belly is formed.

Arteries of the anterior wall of the maxilla in sinus lift surgery.

Knowledge of the anatomical course of the anterior maxillary wall and alveolar process arteries is essential for sinus lift procedures. The aim of this study was to analyse the localization of anastomoses between the infraorbital and posterior superior alveolar artery on 101 computed tomography (CT) scans of maxillary sinuses (patients aged 18-70 years). The distance from the anastomosis to the bone point was measured on CT scans for each tooth location; for edentulous patients measurements were made to the lower edge of the alveolar process, and for dentate patients to the neck of the tooth. Measurements were done independently by two observers. The anastomosis analysed was identified on 50% of CT scans. The distance to the anastomosis was longest above the premolar (20.4 mm from tooth cervical line) and shortest above the first molar (15.9 mm to the edge of the alveolar process). The anastomosis can be localized on a CT scan for exact positioning of the antrotomy in 50% of patients. For the remaining patients, the anatomical information provided in this study can be used to reduce the risk of damage to the anastomosis. This study provides information on the distance from the anastomosis to the neck of preserved teeth in partially edentulous patients, which can be used as a reference point during sinus lift procedures.

Comparative and developmental anatomy of cardiac lymphatics.

The role of the cardiac lymphatic system has been recently appreciated since lymphatic disturbances take part in various heart pathologies. This review presents the current knowledge about normal anatomy and structure of lymphatics and their prenatal development for a better understanding of the proper functioning of this system in relation to coronary circulation. Lymphatics of the heart consist of terminal capillaries of various diameters, capillary plexuses that drain continuously subendocardial, myocardial, and subepicardial areas, and draining (collecting) vessels that lead the lymph out of the heart. There are interspecies differences in the distribution of lymphatic capillaries, especially near the valves, as well as differences in the routes and number of draining vessels. In some species, subendocardial areas contain fewer lymphatic capillaries as compared to subepicardial parts of the heart. In all species there is at least one collector vessel draining lymph from the subepicardial plexuses and running along the anterior interventricular septum under the left auricle and further along the pulmonary trunk outside the heart and terminating in the right venous angle. The second collector assumes a different route in various species. In most mammalian species the collectors run along major branches of coronary arteries, have valves and a discontinuous layer of smooth muscle cells.

Can palmar creases serve as landmarks for the deeper neuro-vascular structures?

PURPOSE: The aim of this study was the examination of the superficial anatomy of palmar creases and their relation to deeper neuro-vascular structures. METHODS: Four creases: distal wrist flexion crease, thenar crease, proximal palmar crease and distal palmar crease were evaluated with reference to the following structures: palmar cutaneous branch of median nerve, palmar cutaneous branch of ulnar nerve, the nerve of Henle, transverse palmar branches from ulnar nerve, recurrent motor branch of median nerve, radial proper palmar digital nerve to the index and the ulnar proper palmar digital nerve to the thumb, Berrettini's communicating branch, ulnar nerve and artery, superficial palmar arch. We performed dissections of 20 cadaveric upper limbs derived from a homogenous Caucasian group. In our study we measured the location of surgically important structures with reference to palmar skin creases. RESULTS: Among the other observations we noticed that the palmar cutaneous branches of the median and ulnar nerves were located at least 0.5 cm away from the thenar crease. The superficial palmar arch was found between the thenar and proximal palmar crease and never crossed the proximal or distal palmar creases. CONCLUSIONS: These anatomical dissections will provide reference material for further ultrasound studies on the arrangements of neuro-vascular structures in reference to superficial palmar creases.