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Purpose Lumbar discogenic diffuse pain is still not understood. Authors describe the sinuvertebral nerve (SVN) as one possible cause. Body-donor studies are rare and controversial. Therefore, the aim was to revisit the origin, course and distribution in a body-donor study. Methods Six lumbar blocks (3 female, 3 male) aged between 59 and 94 years were dissected. After removal of the back muscles, lamina, dura mater and cauda equina, the anterior vertebral venous plexus, spinal artery and SVN were exposed and evaluated. Results 43 nerves out of 48 levels could be evaluated. The origin of the SVN was constituted by two roots: a somatic and a sympathetic branch arising from the rami communicantes. In 4/48 intervertebral canals studied (8.3%), we found two SVN at the same level. In 35/48 cases, one SVN was found. In 9/48 cases, no SVN was found. The SVN had a recurrent course below the inferior vertebral notch; in the vertebral canal it showed different patterns: ascending branch (31/43, 72.1%), common branch diverging into two branches (10/43, 23.3%), double ascending branch (1/43, 2.3%) finalizing two levels above and a descending branch (1/43, 2.3%). In 12/43 cases (27.9%) the SVN had ipsilateral connections with another SVN. The distribution ended in the middle of the vertebral body supplying adjacent structures. Conclusion A thorough understanding of the anatomy of the SVN might lead to significant benefits in therapy of discogenic low back pain. We suggest blocking the SVN at the level of the inferior vertebral notch of two adjacent segments. Level of evidence I Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding

The coracobrachialis muscle (CBM) originates from the apex of the coracoid process, in common with the short head of the biceps brachii muscle, and from the intermuscular septum. The CBM demonstrates variability in both the proximal and distal attachment, with some extremely rare varieties, such as the coracobrachialis superior, coracobrachialis longus and coracocapsularis muscle. This case report describes an extremely rare variant of the coracobrachialis superior muscle, or a very rare variant of the CBM. Our findings highlight the importance of muscle variants in the shoulder region, especially the coracoid region, and are significant for radiologists, anatomists, physiotherapists and surgeons specializing in the shoulder joint.

The aim of the present study is to describe in detail the morphology and innervation pattern of the anconeus muscle, bearing in mind clinical implications such as iatrogenic injuries during surgical elbow approaches. A cadaveric study was performed; 56 elbows from 28 formalin-fixed cadavers belonging to the Anatomy Department of Universidad Complutense of Madrid were dissected. The triceps–anconeus nerve was located and dissected. A second innervation to the anconeus muscle from a branch of the posterior interosseous nerve (PIN) was occasionally detected. Taking the lateral epicondyle as a landmark, the entry points of both nerves in the muscle were referenced, the triceps–anconeus nerve was referenced at 0°, 30°, 45°, 70° and 90° of elbow flexion, and the PIN branch at 0°. Anconeus muscle was present in all specimens. The triceps–anconeus nerve was present in all of the dissected elbows. A branch from PIN to the anconeus muscle was present in 38 of the 54 elbows (70.4%). There were statistically significant differences in all measurements regarding the specimens’ gender, being higher for men. There is evidence of a high frequency of a double innervation pattern for the anconeus muscle: the main branch of triceps–anconeus muscle depending on the radial nerve, which is liable to being damaged during posterior elbow approaches, and a secondary branch depending on the PIN. There are very few references to this finding in Anatomical literature and none with such a large sample size.

There is a general agreement in all fields of sciences that practical pre-graduate education in human anatomy is absolutely necessary. It constitutes an inseparable partner with theoretical learning on the path to knowledge. As such is it critical to (1) establish the set of specific objectives for each practical session (PS), and (2) define more precisely the outcomes (i.e., knowledge, skills and attitudes) that are expected by students. The principle for efficiency of practical sessions (PSs) is that they should take place immediately after didactic sessions of the corresponding topic(s). In this way, students could best reinforce their learning. Considering that the morphology of the human body can be learned by means other than direct observation/dissection of anatomical donors, media, models and imaging have also gained popularity as “anatomy learning tools” in recent years. Imaging is a perfect complement for teaching in the dissecting room, but always in correlation with the reality of bodydonor sections, prosections and dissections of the same region. Anatomical models and computer programs express the reality of the human body, however, anatomical variations and many other qualities (i.e., surgical skills, ethics, pathology, professionalism) can only be appreciated via hands-on use of an anatomical donor to science. Therefore, the anatomical donor remains the Gold Standard for anatomy teaching, especially topographical Anatomy.

The quadriceps femoris has been described as a muscle composed by four heads: rectus femoris, vastus lateralis, vastus medialis and vastus intermedius. Each head fuse with the other ones making up the quadriceps tendon, which inserts into the patella. Nevertheless, there has been described a fifth component of the quadriceps muscle in recent anatomical publications. Understanding this fifth head may be important for orthopedics and radiologist. Cadaveric dissection of left thigh of a female 83 years old was performed to demonstrate a fifth head of the quadriceps femoris muscle. In this study, a fifth head of the quadriceps femoris muscle was found in the left thigh of a female cadaver 83 years old. This fifth head was made up by four independent muscular fascicles attaching in a common flat tendon that joins distally with the lateral border of the quadriceps tendon. The fifth head found was supplied by branches of the ascending branch of the lateral femoral circumflex artery and by branches of the deep lateral division of the femoral nerve. The incidence of this fifth belly in cadaveric studies has been reported as a range from 29 to 100%. However, no published articles refer an anatomical finding such as this multi-bellied fifth head. The knowledge of the existence and location of the fifth belly is necessary to make accurate diagnosis of QF muscle strains. Its anatomical course may be involved in patellar tracking.

Objective The aim of this study is to describe in depth the precise anatomy of the vascular supply of the submandibular gland, trying to determine the existence of patterns of glandular vascularization. Knowledge of these patterns could facilitate surgical management of the gland and the submandibular gland flap. Material and methods Neck dissections of formaldehyde preserved human cadavers were performed. Submandibular and transmandibular approaches were used during the dissections. All the vascular branches found were registered and classified into 2groups: main or accessory branches. The anatomical data analyzed was: The diameter and length of the main and accessory branches, as well as the most important measurements of the submandibular gland flap pedicle. Results 33 glands were dissected to study the arterial supply of the submandibular gland (17 right, 16 left; 17 males, 16 females) and 29 were dissected to study the venous supply (15 left, 14 right; 15 males,14 females). A total of 123 arterial branches were found reaching the 33 submandibular glands (47 main and 76 accessories) and 116 venous branches were found draining the 29 submandibular glands (47 main branches and 69 accessory branches). A constant main venous branch that ran parallel to the Wharton duct and drained in the sublingual vein was found in all of cases (Concomitant Wharton Duct Vein or CWDV). Conclusion The CWDV is a constant venous branch for the drainage of the gland and should be considered as venous pedicle during the dissection of submandibular gland flaps.

Human cadaveric donors are essential for research in the anatomical sciences. However, many research papers in the anatomical sciences often omit a statement regarding the ethical use of the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To rectify this issue, 22 editors-in-chief of anatomical journals, representing 17 different countries, developed standardized and simplified language that can be used by authors of studies that use human cadaveric tissues. The goal of these editor recommendations is to standardize the writing approach by which the ethical use of cadaveric donors is acknowledged in anatomical studies that use donor human cadavers. Such sections in anatomical papers will help elevate our discipline and promote standardized language use in others non anatomy journals and also other media outlets that use cadaveric tissues.

The use of reverse shoulder arthroplasty (RSA) is becoming more extended and its clinical results are good or excellent according to the literature. The main biomechanical characteristic of RSA is that it lowers and medializes the centre of rotation of the shoulder causing an arm lengthening. Although the number of neurological complications is low (5%), there are more neurophysiological changes in the brachial plexus with RSA than with the anatomic shoulder arthroplasty. The main goal of this study was to quantify the lengthening of the terminal branches of the brachial plexus suffered after RSA implantation.20 Embalmed cadavers were analysed. Four distances using bone references were employed to measure the lengthening of the arm and subacromial space. The brachial plexus and its terminal branches (radial, axillary, ulnar, musculocutaneous and median nerves) and the axillary artery, were identified and marked. Measurements were made to determine the change of position of the neurovascular structures, the arm lengthening and the lengthening of each nerve before and after the implantation of RSA. Two models of RSA were used: SMRThe mean arm elongation was 10.5 mm. The subacromial space suffers an elongation of 20.5-29.8%. All the neurovascular structures suffered elongation: median nerve 23.1%, musculocutaneous nerve 22.1%, ulnar nerve 19%, radial nerve 17%, axillary nerve 12-14.5%, axillary artery 24.8%. There were no differences in the results between the types of prosthesis.Due to its design, the RSA causes an arm lengthening which is reflected by the elongation of the neurovascular structures of the arm.

Research within the anatomical sciences often relies on human cadaveric tissues. Without the good will of these donors who allow us to use their bodies to push forward our anatomical knowledge, most human anatomical research would come to a standstill. However, many research papers omit an acknowledgement to the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To remedy this problem, 20 editors-in-chiefs from 17 anatomical journals joined together to put together official recommendations that can be used by authors when acknowledging the donor cadavers used in their studies. The goal of these recommendations is to standardize the writing approach by which donors are acknowledged in anatomical studies that use human cadaveric tissues. Such sections in anatomical papers will not only rightfully thank those who made the donation but might also encourage, motivate, and inspire future individuals to make such gifts for the betterment of the anatomical sciences and patient care.

Resumen Introduccion La descompresion microvascular (DMV) es aceptada como unico tratamiento quirurgico etiologico para la neuralgia del trigemino (NT) clasica refractaria al tratamiento medico. Por ello existe un creciente interes por establecer el valor diagnostico y pronostico de la identificacion de compresiones neurovasculares (CNV) mediante resonancia magnetica (RM) con secuencias tridimensionales de alta resolucion en pacientes con NT clasica candidatos a cirugia. Metodos Este estudio observacional incluye una serie consecutiva de 74 pacientes con NT clasica refractaria intervenidos mediante DMV. En todos los pacientes se realizo una RM tridimensional de alta resolucion con secuencias DRIVE preoperatoria para diagnosticar la existencia de una CNV, asi como su grado, origen y localizacion. Los resultados de la RM fueron analizados de forma «ciega» para los hallazgos de la exploracion quirurgica y posteriormente comparados con estos. Se realizo un seguimiento minimo de 6 meses para comprobar los resultados quirurgicos, que se clasificaron segun la escala de dolor facial del Barrow Neurological Institute (BNI score). El valor pronostico de la RM preoperatoria se analizo mediante una regresion logistica binaria. Resultados La RM preoperatoria con secuencias DRIVE demostro una sensibilidad del 95% y una especificidad del 87%, con un valor predictivo positivo del 98% y un valor predictivo negativo del 70%. Ademas se evidencio un buen grado de concordancia mediante el coeficiente kappa (CK) entre los hallazgos radiologicos y quirurgicos respecto a la existencia de CNV (CK 0,75), al tipo de compresion (CK 0,74) y a la localizacion (CK 0,72), siendo del grado de concordancia moderado para el grado de compresion (CK 0,48). Tras un seguimiento medio de 29 meses (rango 6-100 meses), el 81% de los pacientes presentaban un control del dolor sin o con medicacion (BNI score i - iii ). Los pacientes con un resultado excelente del tratamiento, es decir aquellos sin dolor trigeminal y sin medicacion (BNI score i ) fueron el 66% al final del seguimiento. El analisis univariante mediante regresion logistica binaria demostro que el diagnostico de una CNV en la RM preoperatoria era un factor pronostico favorable que incrementaba significativamente la probabilidad de obtener un resultado excelente (OR 0,17, IC del 95%, 0,04-0,72; p 0,02) o aceptable (OR 0,16, IC del 95%, 0,04-0,68; p 0,01) tras la DMV. Conclusiones La RM DRIVE presenta una elevada sensibilidad y especificidad para el diagnostico preoperatorio de CNV en pacientes con NT clasica refractaria candidatos a tratamiento mediante DMV. El hallazgo de una CNV en el estudio de RM preoperatorio es un factor de buen pronostico para la obtencion de alivio del dolor a largo plazo con la DMV.

Introduction: Microvascular decompression (MVD) is accepted as the only aetiological surgical treatment for refractory classic trigeminal neuralgia (TN). There is therefore increasing interest in establishing the diagnostic and prognostic value of identifying neurovascular compressions (NVC) using preoperative high-resolution three-dimensional magnetic resonance (MRI) in patients with classic TN who are candidates for surgery. Methods: This observational study includes a series of 74 consecutive patients with classic TN treated with MVD. All patients underwent a preoperative three-dimensional high-resolution MRI with DRIVE sequences to diagnose presence of NVC, as well as the degree, cause, and location of compressions. MRI results were analysed by doctors blinded to surgical findings and subsequently compared to those findings. After a minimum follow-up time of six months, we assessed the surgical outcome and graded it on the Barrow Neurological Institute pain intensity score (BNI score). The prognostic value of the preoperative MRI was estimated using binary logistic regression. Results: Preoperative DRIVE MRI sequences showed a sensitivity of 95% and a specificity of 87%, with a 98% positive predictive value and a 70% negative predictive value. Moreover, Cohen's kappa (CK) indicated a good level of agreement between radiological and surgical findings regarding presence of NVC (CK 0.75), type of compression (CK 0.74) and the site of compression (CK 0.72), with only moderate agreement as to the degree of compression (CK 0.48).After a mean follow-up of 29 months (range, 6-100 months), 81% of the patients reported pain control with or without medication (BNI score I–III). Patients with an excellent surgical outcome, i.e. without pain and off medication (BNI score I), made up 66% of the total at the end of follow-up. Univariate analysis using binary logistic regression showed that a diagnosis of NVC on the preoperative MRI was a favourable prognostic factor that significantly increased the odds of obtaining an excellent outcome (OR 0.17, 95% CI 0.04-0.72; P = .02) or an acceptable outcome (OR 0.16, 95% CI 0.04-0.68; P = .01) after MVD. Conclusions: DRIVE MRI shows high sensitivity and specificity for diagnosing NVC in patients with refractory classic TN and who are candidates for MVD. The finding of NVC on preoperative MRI is a good prognostic factor for long-term pain relief with MVD. Resumen: Introducción: La descompresión microvascular (DMV) es aceptada como único tratamiento quirúrgico etiológico para la neuralgia del trigémino (NT) clásica refractaria al tratamiento médico. Por ello existe un creciente interés por establecer el valor diagnóstico y pronóstico de la identificación de compresiones neurovasculares (CNV) mediante resonancia magnética (RM) con secuencias tridimensionales de alta resolución en pacientes con NT clásica candidatos a cirugía. Métodos: Este estudio observacional incluye una serie consecutiva de 74 pacientes con NT clásica refractaria intervenidos mediante DMV. En todos los pacientes se realizó una RM tridimensional de alta resolución con secuencias DRIVE preoperatoria para diagnosticar la existencia de una CNV, así como su grado, origen y localización. Los resultados de la RM fueron analizados de forma «ciega» para los hallazgos de la exploración quirúrgica y posteriormente comparados con estos. Se realizó un seguimiento mínimo de 6 meses para comprobar los resultados quirúrgicos, que se clasificaron según la escala de dolor facial del Barrow Neurological Institute (BNI score). El valour pronóstico de la RM preoperatoria se analizó mediante una regresión logística binaria. Resultados: La RM preoperatoria con secuencias DRIVE demostró una sensibilidad del 95% y una especificidad del 87%, con un valor predictivo positivo del 98% y un valor predictivo negativo del 70%. Además se evidenció un buen grado de concordancia mediante el coeficiente kappa (CK) entre los hallazgos radiológicos y quirúrgicos respecto a la existencia de CNV (CK 0,75), al tipo de compresión (CK 0,74) y a la localización (CK 0,72), siendo del grado de concordancia moderado para el grado de compresión (CK 0,48).Tras un seguimiento medio de 29 meses (rango 6-100 meses), el 81% de los pacientes presentaban un control del dolor sin o con medicación (BNI score I-III). Los pacientes con un resultado excelente del tratamiento, es decir aquellos sin dolor trigeminal y sin medicación (BNI score I) fueron el 66% al final del seguimiento. El análisis univariante mediante regresión logística binaria demostró que el diagnóstico de una CNV en la RM preoperatoria era un factor pronóstico favorable que incrementaba significativamente la probabilidad de obtener un resultado excelente (OR 0,17, IC del 95%, 0,04-0,72; p 0,02) o aceptable (OR 0,16, IC del 95%, 0,04-0,68; p 0,01) tras la DMV. Conclusiones: La RM DRIVE presenta una elevada sensibilidad y especificidad para el diagnóstico preoperatorio de CNV en pacientes con NT clásica refractaria candidatos a tratamiento mediante DMV. El hallazgo de una CNV en el estudio de RM preoperatorio es un factor de buen pronóstico para la obtención de alivio del dolor a largo plazo con la DMV. Keywords: Trigeminal neuralgia, Microvascular decompression, Magnetic resonance, DRIVE, Sensibility, Predictive value, Palabras clave: Neuralgia del trigémino, Descompresión microvascular, Resonancia magnética, DRIVE, Sensibilidad, Valor predictivo

Introduction. The quadriceps femoris consists of four muscles: the rectus femoris, vastus medialis, vastus intermedius, and vastus lateralis. However, the effect of additional quadriceps femoris heads on the vasti muscles and patellar ligaments is unknown. The aims of the present study are to determine the relationship between additional quadriceps femoris heads and the vasti muscles and patellar ligaments and to review the morphology of the vastus lateralis, vastus medialis, and vastus intermedius. Materials and Methods. One hundred and six lower limbs (34 male and 19 female cadavers) fixed in 10% formalin were examined. Results. On all lower extremities, the vastus lateralis consisted of superficial, intermediate, and deep layers. The vastus medialis, on the other hand, consisted of only the longus and obliquus layers. The quadriceps head had one or more supplementary heads in 106 dissected limbs from 68 cadavers (64.1%). The distal portion of the patella was wider in lower limbs without supplementary heads than in type IA but narrower than in type IIIA. In general, the distal portion of the patella was narrower in specimens with a supplementary head than in those without (19.03 SD 3.18 mm vs. 20.58 SD 2.95 mm, p = 0.03817 ). Other patellar ligament dimensions did not differ significantly. Conclusion. The quadriceps femoris muscle is characterized by high morphological variability. Occurrence of extra heads is at the level of 64.1%. The vastus lateralis consists of three parts (superficial, intermediate, and deep), and vastus medialis consists of two (longus and oblique).

Background Anatomic variations in the hepatic venous system are the least understood aspect of hepatic anatomy. The variations are diverse, and data are lacking with respect to the population of Spain and methods of detection. The objective was to examine morphological patterns of variations in hepatic venous vascularization using cadaveric dissections vs. radiological imaging, and to analyze the findings with respect to Spain and to published studies. Methods Thirty-one livers were anatomically dissected and analyzed for their hepatic venous anatomy and then compared to the venous anatomy of livers examined in 216 CT scans from 119 men and 97 women, ranging between 27 and 89 years of age. Statistical analysis was done using the Chi squared and Fisher homogeneity tests. Results The hepatic portal vein showed morphological variations in cadavers vs. CT of 67.3% vs. 67.6% (p-I), 29% vs. 12.2% (p-II), 0% vs. 14.6% (p-III), 0% vs. 14.6% (p-IV), 3.2% vs. 0.5% (p-V) and 6.5% vs. 1.9% (p-VI), respectively in cadavers vs. CT. Hepatic vein pattern variation were found in 64.5% vs. 50.7% (h-I), 32.2% vs. 31.5% (h-II), 0% vs. 2.3% (h-III), 0% vs. 4.7% (h-IV), respectively in dissections vs. CT). In Accessory Hepatic Veins the frequency in pattern variation was 64.5% vs. 18.8% (a-2.1), 29.0% vs. 8.0% (a-2.2), 58.1% vs. 11.3% (a-2.3), 9.7% vs. 0.9% (a-2.4), 67.7% vs. 16.9% (a-2.5), 9.7% vs. 4.2% (a-2.6) and 0% vs. 0.5% (a-2.7), respectively, in cadavers vs. CT. CT showed in 27.2% no accessory hepatic veins. Sex was not a factor influencing patterns of variation. Conclusion Anatomical variants of the hepatic portal vein, the hepatic vein and accessory hepatic veins are very diverse and show greater variability in the specimens compared to those detected with radiological images, finding a wider spectrum of variations as it allows the clinician to have a more precise definition of the vasculature. A higher precision in the definition of anatomical variations is warranted for surgical planning in liver resection and transplantation.

Background The frequency of appearance of anatomical variability in the terminal division of the popliteal artery (PA) is different according to the type of sample used, and ranges from 2% to 21%. The PA locates 1,01 cm behind to the lateral meniscus, which makes it vulnerable during surgical procedures. Iatrogenic injury of the PA or its terminal branches increases if anatomical variables are present. Our aim was to describe and review the branching pattern of the PA in a body-donors to science sample to determine the influence of the sample used (body-donors vs imaging test). Methods A sample consisting of 260 popliteal regions, corresponding to 130 corpses (66 women, 64 men), have been dissected. Multivariate analysis was carried out. Results The terminal division of the PA was classified as follows: Pattern 1: the PA divided into the anterior tibial (ATA) and the posterior tibial arteries (PTA) at the level or distal to the lower border of the popliteal muscle (PM) (94.7%). Pattern 2: the PA bifurcated into the ATA and PTA, proximal to the lower border of the PM (3.3%). Pattern 3: the PA divided at the same level into the ATA, PTA and PEA. (2%). No significant differences between gender and side of the limb could be find. Conclusions We propose a classification that encloses three identifiable groups only. This will allow clinicians to bear in mind these variables easily, at the same time avoiding injuries during surgical procedures such as lateral meniscus repair.

Despite the use of renal denervation to treat hypertension, the anatomy of the renal nervous system remains poorly understood. We performed a detailed quantitative analysis of the human renal nervous system anatomy with the goal of optimizing renal denervation procedural safety and efficacy. Sixty kidneys from 30 human cadavers were systematically microdissected to quantify anatomic variations in renal nerve patterns. Contrary to current clinical perception, not all renal innervation followed the main renal artery. A significant portion of the renal nerves (late arriving nerves) frequently reached the kidney (73% of the right kidney and 53% of the left kidney) bypassing the main renal artery. The ratio of the main renal artery length/aorta-renal hilar distance proved to be a useful variable to identify the presence/absence of these late arriving nerves (odds ratio, 0.001 (95% CI, 0.00002–0.0692; P : 0.001) with a cutoff of 0.75 (sensitivity: 0.68, specificity: 0.83, area under ROC curve at threshold: 0.76). When present, polar arteries were also highly associated with the presence of late arriving nerve. Finally, the perivascular space around the proximal main renal artery was frequently occupied by fused ganglia from the solar plexus (right kidney: 53%, left kidney: 83%) and/or by the lumbar sympathetic chain (right kidney: 63%, left kidney: 60%). Both carried innervation to the kidneys but importantly also to other abdominal and pelvic organs, which can be accidentally denervated if the proximal renal artery is targeted for ablation. These novel anatomic insights may help guide future procedural treatment recommendations to increase the likelihood of safely reaching and destroying targeted nerves during renal denervation procedures.

Purpose The quadriceps femoris (QF) consists of four muscles: the rectus femoris; vastus medialis; vastus lateralis, and vastus intermediate. The tendons of all of these parts join together into a single tendon that attaches to the patella. The QF is a powerful extensor of the knee joint that is needed for walking. A growing number of publications have examined the fifth head of the QF muscle. There is no information about the possibility of other heads, and there is no correct classification of their proximal attachments. Further, the frequency of occurrence of additional heads/components of the QF remains unclear. Methods One hundred and six lower limbs (34 male and 18 female) fixed in 10% formalin solution were examined. Results Additional heads of the QF were present in 64.1% of the limbs. Three main types were identified and included subtypes. The most common was Type I (44.1%), which had an independent fifth head. This type was divided into two subtypes (A-B) depending on its location relative to the vastus intermediate. The second most common type was Type II (30.8%), which originated from other muscles: IIA from the vastus lateralis; IIB from the vastus intermediate, and IIC from the gluteus minimus. In addition, Type III (25%) was characterized by multiple heads: IIIA-two heads with a single common tendon; IIIB-two heads with two separate tendons; IIIC-three heads (lateral, intermediate, medial), and IIID-four heads (bifurcated lateral and bifurcated medial). Conclusion The introduction of a new classification based on a proximal attachment is necessary. The presence of the fifth, sixth, seventh, or eighth head varies.

Clinical and diagnostic variations may occur due to the variable presence of a connection between the median and ulnar nerves in the forearm (Martin-Gruber anastomosis). This incidence has a wide range at 7%-40%. Most commonly, the connection between the nerves is considered to be composed of motor fibers; although, a sensory role has also been described. It is important to note that the number of axons, or the nature of the fibers in this connection, have not yet been elucidated. Fifty upper limbs were examined evaluating morphometric characteristics of the Martin Gruber connection, dissected out, sectioned, and immunohistochemically stained for choline acetyltransferase (ChAT) and analyzed with ImageJ© . The connection was observed in 32% of all cases (16/50). The nerve connections were identified as those in Pattern 1 group (12%-type 1b, 19%-type 1a, and 69%-type 1c) and contained motor (ChAT positive) fibers (40.42 ± 10.5% per connection) with three to four fascicles in each. No statistically significant differences were found according to sex, side, or laterality. There were statistically significant differences in the percentages of ChAT positive fibers; however, this was dependent on the distribution being greater in those not distributed zonally. The presence of this connection is prevalent in almost a third of the cadavers dissected; the understanding of this complex composition in sensory and motor fibers allows for the optimization of diagnosis and treatment of certain median-ulnar nerve injuries. Clin. Anat. 32:501-508, 2019. © 2019 Wiley Periodicals, Inc.

Background The aim of this study was to provide a safe ultrasound-guided minimally invasive surgical approach for a distal tarsal tunnel release concerning nerve entrapments. Methods and results The study was carried out on ten fresh-frozen feet. All of them have been examined by high-resolution ultrasound at the distal tarsal tunnel. The surgical approach has been marked throughout the course of the medial intermuscular septum (MIS, the lateral fascia of the abductor hallucis muscle). After the previous steps, nerve decompression was carried out through a MIS release through a 2.5 mm (± 0.5 mm) surgical portal. As a result, an effective release of the MIS has been obtained in all fresh-frozen feet. Conclusion The results of our anatomic study indicate that this novel ultrasound-guided minimally invasive surgical approach for the release of the MIS might be an effective, safe and quick decompression technique treating selected patients with a distal tarsal tunnel syndrome.

No abstract available. Prof. Dr. Andreas Weiglein was a great scientist and a very good friend. He was a perfect teacher not only in classical gross anatomy but also a perfect promoter in developing alternative methodologies for preservation of bodies such as Thiel’s embalmment and plastination. He served as the President of European Association of Clinical Anatomy for many years and also as the President of the International Society of Plastination for a long time. He was always involved in building bridges between cultures and increasing communication among colleagues from different countries.

Coordination of the various soft palate and pharyngeal muscles should be considered while evaluating velopharyngeal closure. However, it remains unclear whether different muscle bundles have specific functions during velopharyngeal closure. We macroscopically and microscopically examined these muscles in detail and particularly clarified the morphology of the palatopharyngeus (PP) in velopharyngeal closure.Forty halves of 21 heads from Japanese cadavers (average: 83.9 years) were used for analysis; 37 halves of 19 heads were macroscopically examined and 3 halves of 2 heads were histologically examined.The PP consisted of muscle bundles originating from the superior and inferior surfaces of the palatine aponeurosis. The most superior part of the superior constrictor (SC) and most lateral part of PP on the palatine aponeurosis initially ran in parallel and subsequently, in superoposterior and inferoposterior directions, respectively. The PP appeared as a single continuous sheet that was radially spread as a whole. Its medial margins, located superior and inferior to the aponeurosis, formed a fold that established the palatopharyngeal arch. The stylopharyngeus (StP) adjoined the base of this arch.Since PP consisted of muscle bundles running in various directions, various functions of these bundles should be considered during velopharyngeal closure. The PP can function as a sphincter with SC and as an elevator with StP. In addition, PP forms the medial protrusion in collaboration with StP and SC. Thus, PP plays an important role in velopharyngeal closure with the coordination of various muscles.

Throughout history the description and classification of the cranial nerves has been linked to the development and characteristics of anatomy and the role that it played as a tool in providing rationality to medicine, together with social, cultural, religious, and philosophical factors. Anatomists were interested in the cranial nerves, but they disagreed on their number and their paths. We can divide the history of the cranial nerves into three different periods: the first, early or macroscopic period; the second or microscopic period; and the third period or ontogenesis and genoarchitecture. The main aim of this article is to show how the description and knowledge of the cranial nerves were developed in the course of these three periods, and to highlight the main changes produced and the factors related to these changes. We describe how the first period was mainly focused on establishing the definition, number and paths of the cranial nerves, through contributions ranging from Galen's studies in the second century to Sommerring's Doctoral Dissertation in 1778 that described 12 cranial nerves for the first time. Then, the microscopic period was concentrated on the identification of the real nuclei of origin of the different cranial nerves located in the brain stem. Finally came the third period, or ontogenesis and genoarchitecture of the rhombecephalic and mesencephalic cranial nerve nuclei. Anat Rec, 302:381-393, 2019. © 2018 Wiley Periodicals, Inc.

To examine the origin and development of the renal plexus and its relationship to the renal vessels in embryos and early human fetuses. Serial sections of 34 human embryos (stages 16 to 23 of Carnegie, 4 or 5-8 weeks) and 38 fetuses (9-19 weeks) were analyzed. Throughout the embryonic period, the kidney was not innervated by the renal plexus. Those nerves appeared at the beginning of the early fetal period (9 weeks) as branches given off by the immature autonomic abdominal plexus. The renal nerves started to approach to the kidney during the early fetal period at 9-10 weeks of development. They were distributed in close proximity to the renal arteries and their branches. They were observed first with the settlement of the renal veins. The renal artery is present as a branch of the abdominal aorta at stage 19 (between 6 and 7 weeks) prior to development of the renal plexus. The renal veins were not present during the embryonic period but appeared at the start of the fetal period, along with the renal nerves that emerged from segmented sympathetic para-aortic bodies (SPBs). Clin. Anat. 32:272-276, 2019. © 2018 Wiley Periodicals, Inc.

Background Because external laryngeal nerve (ELN) iatrogenic damage is frequent during neck surgery, its precise localization has been highly recommended. This study analyzes the different surgical landmarks previously proposed and the anatomy of the collateral and terminal branches of the ELN. Methods The necks of 157 (77 men and 80 women) human adult embalmed cadavers were examined. The ELN origin, length, and relationship to different landmarks were recorded and results statistically compared with those previously reported. Results The ELN is located deep to the ascending pharyngeal vein in 100% of patients. In most patients, it crosses the carotid axis at the thyroid artery origin level (47% of patients), passes medial to it (89% of patients), and shows an intramuscular trajectory through the inferior constrictor of the pharynx (80% of patients). Conclusion The ELN position, in relation to classical landmarks, is highly variable. The most reliable relationships are those with the ascending pharyngeal vein or with the superior thyroid artery.

The objective of this study is to evaluate the anatomical variability of round and oval window regions and its relationship with their closest structures, to determine its implication on the fitting and stabilization of the middle ear implant Vibrant Soundbridge.Variations of the anatomy of round and oval window regions were assessed in a total of 85 human dissected temporal bones. Afterward, we evaluated the adaptation and subsequent stabilization of the floating mass transducer (FMT) of the Vibrant Soundbridge in 67 cases in round window (RW) and in 22 cases in oval window (OW), and the influence that the variability of the different anatomical features examined had on this stabilization. We also assessed access and surgeon's view of the RW niche through the facial recess approach.Stabilization of the FMT in the RW was achieved in 53 (79%) of the 67 cases; we found that the less favorable anatomical conditions for stabilization were: membrane smaller than 1.5 mm, presence of a high jugular bulb and a narrow or very narrow RW niche. Frequently, two or more of these conditions happened simultaneously. In seven cases (22%) access to the RW through facial recess approach did not allow positioning the FMT in place. OW stabilization succeeded in 18 (82%) of the 22 cases.Round and oval window vibroplasty are difficult surgical techniques. To place the FMT directly on the OW may be easier as we do not have to drill the niche. In both regions there are some anatomical conditions that hinder fitting the FMT and even make it impossible. Once fitted, the main problem is to achieve good stabilization of the device.

The aim of this study was to determine the presence and morphology of the anterolateral ligament (ALL) of the knee in a sample of fetuses. We hypothesized that the ALL is present in sample fetuses and its origin is not related to repetitive stresses throughout life. Forty fresh-frozen knees from cadaveric fetuses were dissected using a standard technique. The ALL and other structures in the anterolateral compartment of the knee were identified. The details of the femoral and tibial attachments, course and relationships with anatomical structures of the ALL were identified, recorded, and quantitatively characterized. The ALL was identified in 100% of the dissected knees. We found three anatomical patterns regarding the femoral attachment: (1) Proximal and posterior to the fibular collateral ligament (55%); (2) Together with the fibular collateral ligament (25%); and (3). Anterior and distal to it (20%). The ALL was extracapsular with an oblique course attaching into the anterolateral aspect of the tibia, midway between the midpoint of Gerdy's tubercle and the fibular head. The ALL has a strong attachment to the lateral meniscus, creating two fascicles: proximal or meniscofemoral and distal or meniscotibial. The ALL is a constant, extracapsular anatomical structure in the anterolateral compartment of the knee, present from the later prenatal period of life. Its morphology shows three different patterns of femoral attachment in relation to the fibular collateral ligament position, a strong attachment in the lateral meniscus, and a constant tibial attachment. Clin. Anat. 30:625-634, 2017. © 2017 Wiley Periodicals, Inc.

Purpose To analyse the variations of the renal arteries in two samples, cadaveric and computerized tomographic (CT) images, as well as to propose a simple classification of such variations based on the obtained results and an extensive review of the literature on the topic. Material and methods Sixty human dissected kidneys and their vessels, and 583 abdominal CT were studied. Results A total of 86 arteries were described in the cadaveric sample, whereas 1223 were analysed in the radiological one. Five types (a–e) and patterns (I–V) have been stablished in the classification. Type a, aortic hilar artery, incidences were 79% in cadavers and 95% in CT; Type b, hilar upper polar artery, incidences were 10% in cadavers and 2% in CT; Type c, aortic upper polar artery, incidences were 5% in cadavers and 2% in CT; Type d, aortic lower polar artery, incidences were 3% in cadavers and 1% in CT; Type e, hilar lower polar artery, incidences were 2% in cadaver and less than 0.1% in CT. The pattern represents the number of arteries reaching one kidney. Patterns I–IV were found in cadavers (I: 78%; II: 19%; III and IV: 2%); in CT sample only patterns I (88%) and II (12%). Pattern V was added because it has been described in the reviewed literature. Conclusions Type a and pattern I are the most prevalent, both in the cadaveric and the CT samples. Also in the consulted literature. There are no differences in the types and pattern incidences by side or sex. A simple, comprehensive and useful classification is proposed.

There is no consensus about the role of the gubernaculum testis (GT). Nineteen human embryos (Carnegie stages 15-23), 36 fetuses (9 weeks to term), and eight neonates were examined. All the embryos and 25 fetuses (from weeks 9-16) were processed for paraffin wax histology and serially sectioned at 10 µm thickness. The remaining 11 fetuses and the eight neonates were fresh specimens that were dissected under a surgical microscope. The GT appeared during the embryonic period (stages 17-23) with a horseshoe-shaped mesenchyme condensation of the superior concavity, which was observed in four different topographical regions sequentially through development. The GT was not attached at either of its ends in any of the specimens, not to the gonad or in the scrotal sac. The inguinal canal differentiates around the inguinal portion of the GT during the late embryonic period. After stage 21, the GT appears enveloped by an evagination of the peritoneal cavity. It has few striate muscular fibers and vessels. Although the GT does not appear to have the role traditionally attributed to it, it is still an essential structure and indirectly facilitates the descent of the testes. It contributes to the formation of the inguinal canal and then forges the pathway that the testes will subsequently take through the inguinal canal as they migrate from the abdominal cavity into the scrotal sac. Clin. Anat. 30:599-607, 2017. © 2017 Wiley Periodicals, Inc.

This Special Issue entitled "Cranial Nerves: phylogeny, ontogeny, morphology and clinical significance" has been divided into two consecutive volumes. This second volume is devoted to morphology and clinical relevance. Articles in this volume examine these topics from a macroscopic point of view and with a surgical interest. This volume includes articles on oculomotor nerves III, IV, and VI and their course in the orbit; intracranial and extracranial views of the V and VII pairs; and branching patterns of IX, X, XI, and XII pairs with medical significance. Together, these articles provide a general overview of cranial nerves' gross anatomical organization, as well as improving on the knowledge necessary for clinical approaches. Anat Rec, 302:555-557, 2019. © 2019 Wiley Periodicals, Inc.

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.

Catheter-based renal denervation techniques focus on reducing blood pressure in resistant hypertension. This procedure requires exact knowledge of the anatomical interrelation between the renal arteries and the targeted renal nervous plexus. The aim of this work was to build on classical anatomical studies and describe the gross anatomy and anatomical relationships of the renal arteries and nerve supply to the kidneys in a sample of human cadavers. Twelve human cadavers (six males and six females), age range 73 to 94 years, were dissected. The nervous fibers and renal arteries were dissected using a surgical microscope. The renal plexus along the hilar renal artery comprised a fiber-ganglionic ring surrounding the proximal third of the renal artery, a neural network along the middle and distal thirds, and smaller accessory ganglia along the course of the nerve fibers. The fibers of the neural network were mainly located on the superior (95.83%) and inferior (91.66%) surfaces of the renal artery and they were sparsely interconnected by diagonal fibers. Polar arteries were present in 33.33% of cases and the renal nerve pattern for these was similar to that of the hilar arteries. Effective renal denervation needs to target the superior and inferior surfaces of the hilar and polar arteries, where the fibers of the neural network are present. Clin. Anat. 29:660-664, 2016. © 2016 Wiley Periodicals, Inc.

Despite the use of renal denervation (RDN) to treat hypertension, the anatomy of the renal nervous system remains poorly understood. We performed a detailed quantitative analysis of the human renal nervous system anatomy with the goal of optimizing RDN procedural safety and efficacy. Sixty kidneys

Differential diagnosis between normal/variant anatomy and pathological/traumatic findings represents one of the main matters of investigation of the so-called forensic clinical anatomy. In the literature, many anatomical variations of the laryngeal thyroid cartilage have been reported, with potential implications in forensic pathology. They include triticeal cartilages, foramen thyroideum, asymmetry, segmentation or agenesis of the superior thyroid horns, bone connections with the hyoid bone, absence of cricothyroid facets, hypertrophy of the inferior thyroid tubercle, and asymmetries in the thyroid notch, isthmus, or length of the inferior horn. In this report, we describe a laryngeal anatomical variation never described before, consisting of 2 apophyses symmetrically arising from the posterior margins of the thyroid laminae. Postmortem computed tomography performed on the laryngeal visceral block excluded previous traumatic injuries or natural pathologies of the laryngeal cartilages, confirming the congenital origin of the finding. An "omega epiglottis" and 3 laryngeal cysts in the piriform sinuses also coexisted, suggesting the possibility of underlying common developmental mechanisms.

Background The aim of this study is to provide a safe ultrasound-guided minimally invasive surgical approach for a proximal tarsal tunnel release concerning nerve entrapments. Methods and results The study was carried out on ten fresh-frozen feet. All of them were examined by high resolution ultrasound at the medial ankle region. The surgical approach was marked throughout the course of the flexor retinaculum (laciniate ligament). Once the previous steps were done, the flexor retinaculum release technique was carried out with a 2-mm entry only. As a result, an effective and safe release of the flexor retinaculum was obtained in all fresh-frozen feet. Conclusion The results of our anatomic study indicate that our novel ultrasound-guided minimally invasive surgical approach for the release of the flexor retinaculum might be an effective, safe and quick decompression technique treating selected patients with a proximal tarsal tunnel syndrome.

This Special Issue, entitled "Cranial Nerves: phylogeny, ontogeny, morphology and clinical significance," has been divided into two consecutive volumes. We present here the first volume, devoted to phylogeny and ontogeny. Articles in this volume examine these two topics from a microscopic point of view. This volume includes an historical review that serves as an introduction. It also includes a review of the organization of cranial nerves from a neuromeric perspective which, together with two articles in amphioxi and lampreys, give emphasis to a comparative approach. Finally, several articles examine cranial nerves zero (nervus terminalis), I (olfactory), II (optic), III, IV and VI (oculomotor), VIII (cochlear and vestibular), and XI (accessory or spinal). Together, they provide a general overview of the neuroanatomical organization of cranial nerves, while offering insights into an evo-devo paradigm. Anat Rec, 302:378-380, 2019. © 2019 Wiley Periodicals, Inc.

The masseteric nerve (MN) and the anterior branch of the obturator nerve (ON) that innervate the transferred gracilis muscle have proved highly efficient for reanimating paralyzed facial muscles when muscle transfer is required. Previous researchers have published the total axonal load for myelinated fibers in both nerves. However, the real motor axonal load has not been established. We performed the study on 20 MN and 13 ON. The segments of the MN and the ON were embedded in paraffin, sectioned at 10 μm, and stained following a standard immunohistochemical procedure using anti-choline acetyltransferase to visualize the motor fibers. The MN has a higher axonal load than the ON. There were statistically significant differences between the axonal load of the proximal segment of the MN and the ON. These findings confirm that end-to-end anastomoses between the MN and the ON should preferably use the proximal segment. However, MN neurotomy should ideally be performed between the proximal and distal segments, preserving innervation to the deep fascicles. Our results show that the MN is ideal as a donor motor nerve for reinnervating transplanted muscle for dynamic reanimation of the paralyzed face. The neurotomy should ideally be performed between the first and second collateral branches of the MN. Clin. Anat. 32:612-617, 2019. © 2019 Wiley Periodicals, Inc.

Objectives/Hypothesis It has been generally accepted that the branches of the internal branch of the superior laryngeal nerve to the interarytenoid muscle are exclusively sensory. However, some experimental studies have suggested that these branches may contain motor axons, and therefore that the interarytenoid muscle is supplied by both the superior and recurrent laryngeal nerves. The aim of this work was to determine whether motor axons to the interarytenoid muscles are present in both laryngeal nerves. Study Design Basic research. Methods Twelve human internal branches of the superior laryngeal nerve were dissected, and its branches to the interarytenoid muscle were removed and processed for choline-acetyltransferase immunohistochemistry, a method not used previously in studying the nerve fiber composition of the laryngeal nerves. Results The internal branch of the superior laryngeal nerve divided into two to five branches to the interarytenoid muscle. All branches contained motor axons, with the proportion of motor axons varying from 6% to 31%. Conclusion The present study confirms that the internal branch of the superior laryngeal nerve provides a motor innervation to the interarytenoid muscles. Level of Evidence N/A. Laryngoscope, 2015

The superior mesenteric artery (SMA) supplies irrigation to the small intestine, ascending and a variable area of the transverse colon. Although medical imaging and surgical procedures have been widely developed in the last decades, the anatomy of the SMA using advanced imaging technology remains to be elucidated. Previous studies have used small sample sizes of cadaveric or radiological samples to propose a number of classifications for the SMA. In this study, we aimed to provide a more detailed description and useful classification of the SMA and its main branches [middle colic artery (MCA), right colic artery (RCA), and ileocolic artery (ICA)]. Samples (n = 50, 28 males and 22 females) were obtained from the repository of human cadavers located at the Department of Human Anatomy and Embryology, Complutense University of Madrid. This sample was dissected by preclinical medical students and completed by two of the authors (Gamo and Jiménez). A second set of samples was obtained from a bank of computerized tomography (CT) (560 CTs, 399 males and 161 females) collected by the Radiology Department at the Clínico San Carlos Hospital, Spain. Based on the results obtained from these studies, we propose a new classification of four patterns for the SMA anatomy. Pattern I as the independent origin of the three main branches of the SMA (cadaveric 40 %; CT 73.69 %); Pattern II is subdivided in three sub-patterns based on the common trunks of origin: Pattern IIa, common trunk between RCA and MCA (cadaveric 20 %, CT 4.28 %); Pattern IIb, common trunk between RCA and ICA (cadaveric 32 %, CT 15 %); Pattern IIc, common trunk for the three main branches (cadaveric 0 %, CT 0.35 %); Pattern III, as the absence of RCA (cadaveric 8 %; CT 2.32 %) and Pattern IV, based on presence of accessory arteries (not found in any of the samples). Although the independent origin of the three colic arteries have been classically described as the most frequent, the right colic artery is responsible of major variations.

Throughout history the description and classification of the cranial nerves has been linked to the development and characteristics of anatomy and the role that it played as a tool in providing rationality to medicine, together with social, cultural, religious, and philosophical factors. Anatomists were interested in the cranial nerves, but they disagreed on their number and their paths. We can divide the history of the cranial nerves into three different periods: the first, early or macroscopic period; the second or microscopic period; and the third period or ontogenesis and genoarchitecture. The main aim of this article is to show how the description and knowledge of the cranial nerves were developed in the course of these three periods, and to highlight the main changes produced and the factors related to these changes. We describe how the first period was mainly focused on establishing the definition, number and paths of the cranial nerves, through contributions ranging from Galen’s studies in the second century to Sömmerring’s Doctoral Dissertation in 1778 that described 12 cranial nerves for the first time. Then, the microscopic period was concentrated on the identification of the real nuclei of origin of the different cranial nerves located in the brain stem. Finally came the third period, or ontogenesis and genoarchitecture of the rhombecephalic and mesencephalic cranial nerve nuclei.

Introduction The extrapetrous course of the facial nerve has been a matter of study and debate since XIX century. Two different classifications have been classically proposed and widely accepted by most of the authors. Nevertheless, there are reported cases which do not fit in any of those. The aim of this study is to propose a new and useful classification. Material and methods We have used 23 embalmed Caucasian adult cadavers (11 male and 12 female) belonging to the Bodies Donation and Dissecting Rooms Centre of the University Complutense of Madrid. The extra-petrous facial nerve was dissected in the possible specimens resulting in 38 facial nerves. The studied parameters were length, diameter of divisions, terminal branches, and nerve connections. Results In every specimen two main divisions were found, temporofacial and cervicofacial. They divided into five terminal branches from cranial to caudal: temporal, zygomatic, buccal, marginal or mandibular, and cervical. Based on the comparison with previous proposed classifications, we have unified the patterns in 12 types being the most frequent types the type 3 (eight cases, 21.05%), with connections between temporal, zygomatic and buccal branches and the type 8 (eight cases, 21.05%), a complex network between temporal, zygomatic, buccal, and mandibular branches. The number of terminal branches was so variable. Conclusion We propose a new 12-patterned classification which summarizes the previous ones. However, we consider that a good study of the number of terminal branches, connections between branches or with other cranial nerves are more useful for surgeons to avoid injuries to the facial nerve during surgery than complex classifications. Anat Rec, 302:599-608, 2019. © 2018 Wiley Periodicals, Inc.

Changes in motoneurons innervating laryngeal muscles after section and regeneration of the recurrent laryngeal nerve (RLN) are far from being understood. Here, we report the somatotopic changes within the nucleus ambiguus (Amb) after the nerve injury and relates it to the resulting laryngeal fold impairment. The left RLN of each animal was transected and the stumps were glued together using surgical fibrin glue. After several survival periods (1, 2, 4, 8, 12, 16 weeks; at least six rats at each time point) the posterior cricoarytenoid (PCA) and thyroarytenoid (TA) muscles were injected with fluorescent-conjugated cholera toxin and the motility of the vocal folds evaluated. After section and subsequent repair of the RLN, no movement of the vocal folds could be detected at any of the survival times studied and the somatotopy and the number of labeled motoneurons changed. From 4 wpi award, the somatotopy was significantly disorganized, with the PCA motoneurons being located rostrally relative to their normal location. A rostrocaudal overlap between the two pools of motoneurons supplying the PCA and TA muscles was observed from 2 wpi onwards. Hardly any labeled neurons were found in the contralateral Amb in any of the experimental groups. An injury of the RLN leads to a reinnervation of the denervated motor endplates of PCA and TA. However, misdirected axons sprout and regrowth from the proximal stump to the larynx. As a result, misplaced innervation of muscles results in a lack of functional recovery of the laryngeal folds movement following a RLN injury.

In spite that vascular inconvenients or immunological rejections have been solved in relation with larynx transplant, a successful functional reinnervation has not been achieved. Some studies have suggested that laryngeal nerve connection may contain motor fibers, which could explain unexpected evoked responses in electromyographic studies or the different positions adopted of the vocal folds after similar nerve lesions. Ten patients with unexpected evoked responses after laryngeal nerve stimulation were selected. All the patients underwent a total laryngectomy due to oncological causes. In every case, laryngeal nerve connections were observed. All of them were morphologic and histologic processed for choline-acetyltransferase immunohistochemistry. The presence of motor axons in the nerve connections has been demonstrated, which would explain that the motor innervation to the laryngeal muscles could be dual through these variable connections. This also would justify the difficulty of carrying out laryngeal nerve reinnervation procedures. Anat Rec, 302:646–651, 2019. © 2018 Wiley Periodicals, Inc.

Neurons innervating the intrinsic muscles of the larynx are located within the nucleus ambiguus but the precise distribution of the neurons for each muscle is still a matter for debate. The purpose of this study was to finely determine the position and the number of the neurons innervating the intrinsic laryngeal muscles cricothyroid, posterior cricoarytenoid, and thyroarytenoid in the rat. The study was carried out in a total of 28 Sprague Dawley rats. The B subunit of the cholera toxin was employed as a retrograde tracer to determine the locations, within the nucleus ambiguus, of the neurons of these intrinsic laryngeal muscles following intramuscular injection. The labelled neurons were found ipsilaterally in the nucleus ambiguus grouped in discrete populations with reproducible rostrocaudal and dorsoventral locations among the sample of animals. Neurons innervating the cricothyroid muscle were located the most rostral of the three populations, neurons innervating the posterior cricoarytenoid were found more caudal, though there was a region of rostrocaudal overlap between these two populations. The most caudal were the neurons innervating the thyroarytenoid muscle, presenting a variable degree of overlap with the posterior cricoarytenoid muscle. The mean number (6SD) of labelled neurons was found to be 41 6 9 for the cricothyroid, 39 6 10 for the posterior cricoarytenoid and 33 6 12 for the thyroarytenoid. Anat Rec, 296:470–479, 2013. V C 2013 Wiley Periodicals, Inc.

Background Bleeding within the supraglottic region can be a lethal complication after CO2 laser microsurgery. Our aim was to propose endoluminal anatomical landmarks to locate the superior laryngeal vessels resulting in a safer microsurgery. Methods Endoluminal dissections were made in 22 larynges without laryngeal disease. Results The neurovascular structures were in the superior third of a triangle defined by the vocal process, the anterior commissure, and the epiglottic attachment of the aryepiglottic fold. They overlapped in 4 different ways: pattern I (70.4%): superior laryngeal vein (SLV), superior laryngeal artery (SLA), and internal laryngeal nerve (ILN); pattern II (13.6%): SLA, SLV, ILN; pattern III (4.6%): SLV, ILN, and SLA; pattern IV (4.6%): SLA, ILN, and SLV. Conclusion Microsurgery in the supraglottic region may be safer if surgeons are aware of the superior third of the above-defined triangle, “danger area”, where the vascular elements of this region are located. © 2012 Wiley Periodicals, Inc. Head Neck, 2013