Connections between postparotid terminal branches of the facial nerve: An immunohistochemistry study

It has been assumed that connections between the postparotid terminal branches of the facial nerve are purely motor. However, the nature of their fibers remains unexplored. The aim of this study is to determine whether these connections comprise motor fibers exclusively. In total 17 connections between terminal facial nerve branches were obtained from 13 different facial nerves. Choline acetyltransferase antibody (ChAT) was used to stain the fibers in the connections and determine whether or not all of them were motor. All connections contained ChAT positive and negative fibers. The average number of fibers overall was 287 (84–587) and the average proportion of positive fibers was 63% (37.7%–91.5%). In 29% of the nerves, >75% of the fibers were ChAT+ (strongly positive); in 52.94%, 50%–75% were ChAT+ (intermediately positive); and in 17.65%, <50% were ChAT+ (weakly positive). Fibers traveling inside the postparotid terminal cranial nerve VII branch connections are not exclusively motor

Effect of pedicle screw augmentation with a self-curing elastomeric material under cranio-caudal cyclic loading—a cadaveric biomechanical study

Abstract Background Pedicle screws can be augmented with polymethylmethacrylate (PMMA) cement through cannulated and fenestrated pedicle screws to improve screw anchorage. To overcome the drawbacks of PMMA, a modified augmentation technique applying a self-curing elastomeric material into a balloon-created cavity prior to screw insertion was developed and evaluated. The aim of the study was to compare the effect of the established and novel augmentation technique on pedicle screw anchorage in a biomechanical in vitro experiment. Methods In ten lumbar vertebral bodies, the right pedicles were instrumented with monoaxial cannulated and fenestrated pedicle screws and augmented in situ with 2 ml PMMA. The left pedicles were instrumented with monoaxial cannulated pedicle screws. Prior to left screw insertion, a balloon cavity was created and filled with 3 ml of self-curing elastomer (silicone). Each screw was subjected to a cranio-caudal cyclic load starting from − 50 to 50 N while the upper load was increased by 5 N every 100 load cycles until loosening or 11,000 cycles (600 N). After cyclic loading, a pullout test of the screws was conducted. Results The mean cycles to screw loosening were 9824 ± 1982 and 7401 ± 1644 for the elastomer and PMMA group, respectively (P = 0.012). The post-cycling pullout test of the loosened screws showed differences in the failure mode and failure load, with predominantly pedicle/vertebrae fractures in the PMMA group (1188.6 N ± 288.1) and screw pullout through the pedicle (671.3 N ± 332.1) in the elastomer group. Conclusion The modified pedicle screw augmentation technique involving a balloon cavity creation and a self-curing elastomeric silicone resulted in a significantly improved pedicle screw anchorage under cyclic cranio-caudal loading when compared to conventional in situ PMMA augmentation

Study of the Anatomical Association between Morton&rsquo;s Neuroma and the Space Inferior to the Deep Transverse Metatarsal Ligament Using Ultrasound

Morton&rsquo;s neuroma (MN) is a common condition in clinical practice. The compressive etiology is the most accepted, in which compression occurs in the tunnel formed by the adjacent metatarsals, the deep transverse metatarsal ligament (DTML) and the plantar skin. Ultrasound (US) is a reliable method of study. The presence of insufficient space under the DTML may be related to the appearance of MN. Objectives: To verify the relationship between MN and the space under the DTML between the metatarsal heads of the third (M3) and the fourth (M4) metatarsals using US. Methods: This is a cross-sectional epidemiological study. The research study using the ultrasound (US) technique was carried out on 200 feet belonging to 100 patients aged 18 to 65 of both sexes, with a control group formed by 62 patients and a study group formed by 38 patients diagnosed with MN. Results: The presence of MN and the factors associated with it were studied in 100 patients using ultrasound (US). The assessment and comparison with US of the space inferior to the DTML between M3 and M4 in control groups and patients with MN show that patients with MN have a smaller size in the variable &ldquo;h&rdquo; (height or distance DTML-plantar skin), in the variable &ldquo;b&rdquo; (base or intermetatarsal distance M3 and M4) and in the variable &ldquo;s&rdquo; (surface of the parallelogram &ldquo;h&rdquo; &times; &ldquo;b&rdquo;). The predictors of MN are a decrease in dimension &ldquo;b&rdquo; and an increase in weight. Sitting in an office chair and the use of a bicycle, due to equinus, have an influence on the space below the DTML, reducing it and promoting the appearance of MN. Conclusions: The two US measurements (&ldquo;h&rdquo; and &ldquo;b&rdquo;) in the space below the DTML are smaller in patients with MN than in the asymptomatic group. A shorter distance between M3 and M4, and an increase in BMI are predictors of MN

How to Differentiate Pronator Syndrome from Carpal Tunnel Syndrome: A Comprehensive Clinical Comparison

The diagnostic process that allows pronator syndrome to be differentiated reliably from carpal tunnel syndrome remains a challenge for clinicians, as evidenced by the most common cause of pronator syndrome misdiagnosis: carpal tunnel syndrome. Pronator syndrome can be caused by compression of the median nerve as it passes through the anatomical structures of the forearm, while carpal tunnel syndrome refers to one particular topographic area within which compression occurs, the carpal tunnel. The present narrative review is a complex clinical comparison of the two syndromes with their anatomical backgrounds involving topographical relationships, morphology, clinical picture, differential diagnosis, and therapeutic options. It discusses the most frequently used diagnostic techniques and their correct interpretations. Its main goal is to provide an up-to-date picture of the current understanding of the disease processes and their etiologies, to establish an appropriate diagnosis, and introduce relevant treatment benefiting the patient

Infraorbital canal variants and its clinical and surgical implications. A Systematic Review.

Describing the infraorbital canal's variations is important to anesthesia, diagnositc by imaging and for surgery planning. Hence, we carried out a sistematic review in order to identify these variants and see what clinical relevance each of them has

The carotid axis revisited

The aim was to determine the variations in the level of origin of carotid bifurcation and diameters of the common, internal, and external carotid arteries which is clinically important for several interventional procedures. Therefore, 165 human embalmed corpses were dissected. The data collected were analyzed using the Chi square-test and the Pearson correlation test. The results of previous studies have been reviewed. In relation to the level of the carotid bifurcation, taking as a reference point the hyoid bone, the values ranged from 4 cm below the hyoid body to 2.5 cm above the body of the hyoid, being the average height—0.33 cm, with a standard deviation of 1.19 cm. The right carotid bifurcation was established at a higher level (x = − 0.19 cm.) than the left one (x = − 0.48 cm.) (p = 0.046). On the contrary, no significant gender differences could be observed. The arterial calibres of the common and internal carotid arteries were higher in male than female. In the internal carotid artery (X = 0.76 cm.), the left was greater than the right (X = 0.72 cm.) (P = 0.047). However, no differences in the distribution of the calibre of the external carotid artery were found neither by side nor gender. Variations in the level of bifurcation and calibres of carotid arteries are relevant for interventional radiology procedures and head and neck surgeries. Knowledge of these anatomical references might help clinicians in the interpretation of the carotid system.Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu

The bronchial segmentation and its anatomical variations. A clinical-anatomic and bronchoscopy study

The development in interventional respiratory medicine entails the need of bronchial anatomical knowledge, whose variations assume their greatest importance nowadays. The aim of this study was to describe the frequency of these variations and to analyze the bronchial lengths, barely registered before in literature. This observational descriptive study (from June 2018 until April 2019) was conducted in a sample of 17 pairs of lungs, which were dissected and measured at the Cadaver Donation Centre (Universidad Complutense, Madrid), and a second sample of 50 bronchoscopies, performed at the San Carlos Clinic Hospital, which were analyzed during the procedure. Our results show that there are no significant differences in the incidence of variations by sex in any of both samples, and neither in the average length of any bronchus by sex nor lobar pattern. Left main bronchus presents the longest length and left upper lobe bronchus the shortest. The highest percentage of variations is contained in the right lower lobe (25.4%), and the most frequent variation in the subsuperior bronchus (B*) (19.4%). The middle lobe and the left lower lobe present the lowest percentage of variations (11.9%). Only 37.3% of the pairs of lungs/patients did not have any anatomical variation in the general sample. Despite of the small size of the sample, results show a high percentage of variations and a minority of completely normal pairs of lungs, which invites us to reflect about the probable high prevalence of variations in the general population. Further studies with greater samples are needed to confirm our hypothesis.Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu

Connections between postparotid terminal branches of the facial nerve: An immunohistochemistry study

It has been assumed that connections between the postparotid terminal branches of the facial nerve are purely motor. However, the nature of their fibers remains unexplored. The aim of this study is to determine whether these connections comprise motor fibers exclusively. In total 17 connections between terminal facial nerve branches were obtained from 13 different facial nerves. Choline acetyltransferase antibody (ChAT) was used to stain the fibers in the connections and determine whether or not all of them were motor. All connections contained ChAT positive and negative fibers. The average number of fibers overall was 287 (84-587) and the average proportion of positive fibers was 63% (37.7%-91.5%). In 29% of the nerves, >75% of the fibers were ChAT+ (strongly positive); in 52.94%, 50%-75% were ChAT+ (intermediately positive); and in 17.65%, <50% were ChAT+ (weakly positive). Fibers traveling inside the postparotid terminal cranial nerve VII branch connections are not exclusively motor

Atheromatosis of the brain-supplying arteries: Circle of Willis, basilar, vertebral and their branches

Purpose: Atherosclerotic plaques in the brain-supplying arteries are slowly-developing alterations of vascular structures that can lead to neurological impairment due to stenosis and insufficient oxygenation of eloquent brain areas. The aim of this study is to provide detailed demographic information related to the incidence of atherosclerotic plaques in the cerebral arteries. Material and methods: Forty-eight circles of Willis (21 men, 21 women, mean age: 70.26, six samples unknown) were macroscopically analyzed for length, diameter, and presence of atherosclerotic plaques. Statistical analysis was used to identify potential differences in the locations and frequencies of atherosclerotic plaques in relation to age and sex. Results: The study sample revealed 261 atherosclerotic plaques. The key findings were significant correlations between plaque development and age and between plaque location and age; however, there was no significant sex difference. Conclusion: The upper and lower branches of the middle cerebral artery (MCA) were novel locations predisposing to plaque development. A cut-off value at 60 years revealed a significant difference in plaque development and distribution. There were no significant sex differences in the occurrence of atherosclerotic plaques.Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu