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PURPOSE: Depending on its axis, pronation varies from the radius rotation around the steady ulna to the reciprocal adduction of the radius and abduction of the ulna. While there is no question that pronator teres is a central pronation agonist, anconeus's role is not settled. The current investigation comparing palpation and ultrasonography in these two muscles during pronation along the axis capitulum-second digit evolved from a serendipitous finding in a clinical anatomy seminar. METHODS: Single-hand palpation and two-transducer ultrasonography over anconeus and pronator teres were used on ten normal subjects to investigate their contraction during pronation around the capitulum-second digit axis. These studies were done independently and blind to the results of the other. The statistical analysis between palpation and ultrasonography was performed with Cohen's kappa coefficient and the χ2 test. RESULTS: On palpation, on resisted full pronation, anconeus contracted in 8/10 subjects and pronator teres in 10/10 subjects. Without resistance, the corresponding ratios were 5/10 and 9/10. On two-transducer ultrasonography, the comparable ratios were 7/10 and 10/10, and 3/10 and 10/10. A fair concordance (Cohen's kappa = 0.21) between palpation and ultrasonography in detecting the simultaneous status of anconeus and pronator teres during resisted full pronation. Anatomic dissection illustrated the elements involved. CONCLUSIONS: Plain palpation confirmed by ultrasonography showed the simultaneous contraction of anconeus and pronator teres during resisted pronation in most of the studied subjects. The study suggests that palpation can be helpful in directly studying muscle activity during movement.

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BACKGROUND: Palpation, a traditional haptic ability, is used daily by practitioners of all medical and surgical specialties to assess patients. In the current study, one of the authors, in a routine clinical setting, was able to deduce the dynamic features of the putative inferior belly of omohyoid. This led to a proof-of-concept study that yielded results consistent with the clinical findings. METHODS: The first part of the study involved a survey of 300 rheumatic disease patients in whom the greater supraclavicular fossa was explored by palpation. While the patient kept the head straight, the clinician placed his middle three fingers 2.5-3 cm dorsal to the clavicle in the window between the sternocleidomastoid and trapezius clavicular insertions, explored the supraclavicular fossa, and palpated the paired contractile inferior belly of the assumed omohyoid during flexion in the three orthogonal planes. In the second part of the study, five normal subjects were examined in a similar manner by the same clinician and had independent ultrasonography performed on the dominant side. Descriptive statistics were used, and Yates' corrected chi-squared test was applied to certain nominal variables. Additionally, a comparative anterolateral bilateral neck dissection was performed in a cadaveric specimen. RESULTS: Both studies showed that the contractile structure was the inferior belly of omohyoid and that its contraction occurred during anterior neck flexion and was opposite to the side of neck rotation, resembling the sternocleidomastoid. CONCLUSIONS: Palpation uncovered a previously unknown function of the inferior belly of omohyoid, suggesting that physical examination of the musculoskeletal system based on palpation may lead to hypotheses worthy of exploration.

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Among the non-metrical variants of the mandible that have been proven to be a key issue for dental practitioners, the retromolar foramen constitutes one of the most controversial details regarding its prevalence and associated variables. Thus, this study evaluated the prevalence of the retromolar foramen and the variables associated with its presence in a large Spanish collection of human dry mandibles from the nineteenth century. Six hundred Spanish human dry mandibles (1200 sides) belonging to an osteology collection were examined. The presence of teeth, the presence or absence of retromolar foramen, as well as its side, diameter, number, and location were evaluated. Descriptive analysis and analysis of the associations between the variables were performed. The retromolar foramen was observed in 184 mandibles (31%) and was predominantly present unilaterally (60.8%). Most mandibles (54.9%) had a single foramen. The most common location was the retromolar trigone region (84%). On analysis of the association of variables, it was observed a strong association (p < 0.001) between the presence or absence of the foramen and the presence of teeth. Moreover, a significant association was also found between sex vs. presence of teeth (p = 0.033), sex vs. presentation side of the foramen (p = 0.028), sex vs. number of foramina found (p = 0.004), and diameter vs. number of foramina found (p < 0.001). This study reveals that the retromolar foramen showed a high prevalence of 31% in nineteenth century Spaniards and was located primarily in the retromolar trigone, suggesting that dentists should be aware of and consider the relevant findings of this study.

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This study aimed to determine by ultrasonography, and cadaveric dissection, whether the firm cords felt by palpation at the sides of the proximal phalanx (PP), actively flexing, and extending the proximal interphalangeal (PIP) joint while keeping the metacarpophalangeal (MCP) joint extended are the lateral bands (LBs) of the extensor apparatus. If so, palpation of the LBs could help evaluate hand conditions that impact the digits' intrinsic muscles. To this end, the PP of the middle and ring fingers of the dominant hand of seven subjects were studied by palpation on both sides. Ultrasonography (US) was performed with a hockey-stick transducer placed on the ulnar side. Five cadaveric hands were dissected, exposing the dorsal extensor apparatus. On palpation, a firm cord was consistently felt at the PP's sides in all subjects. These cords moved widely forward on PIP flexion and backward with PIP extension. By US scanning, the cords corresponded to the LBs. However, the forward movement had only a median of 1.8 mm (range 0.7-3 mm) in the middle finger and a median of 1.1 mm (range 0.3-2.7 mm) in the ring finger compared with an estimated 5-10 mm upon palpation. Cadaveric dissection confirmed the forward movement of the LBs in PIP flexion. We concluded that the firm cords felt at the PP sides are the LBs of the extensor apparatus. We confirmed their movement with the active flexion/extension of the PIP joint. Comparing the wide palpatory and the meager US motion, a haptic illusion of motion may be present.

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SUMMARY: During routine dissection of a left upper limb of a 68-year-old male human cadaver, an unusual muscle was observed originating from the radius and flexor retinaculum, and continued in the hypothenar region with the muscle belly of the abductor digiti minimi. We checked that it was an accessory abductor digiti minimi (ADM). Its muscular belly was in close relation to the median and ulnar nerves. We review the literature regarding such muscle variations and discuss the potential for compression of the median and ulnar nerves. Although the accessory ADM is usually asymptomatic and only rarely results in nerve compression, it should be taken into account by surgeons when establishing a differential diagnosis in the compression neuropathies of the median and ulnar nerves. An ultrasound scanning can help establish the differential diagnosis.

RESUMEN: Durante la disección de rutina de un miembro superior izquierdo de un cadáver humano masculino de 68 años, se observó un músculo inusual que se originaba en el radio y el retináculo flexor del carpo, y continuuaba en la región hipotenar con el vientre muscular del abductor digiti minimi manus. Verificamos que se trataba del músculo abductor digiti minimi accessorius (ADMA). Su vientre muscular se encontraba en estrecha relación con los nervios mediano y ulnar. Revisamos la literatura sobre variaciones musculares y discutimos la potencial compresión de los nervios mediano y ulnar. Aunque el ADMA suele ser asintomático y rara vez produce compresión nerviosa, los cirujanos deben tenerlo en cuenta al establecer un diagnóstico diferencial en las neuropatías de compresión de los nervios mediano y ulnar. Una ecografía puede ayudar a establecer el diagnóstico diferencial.

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SUMMARY: Positive effects on reducing students' stress have been reported across numerous university settings when anatomy preparatory seminars have been provided. To date, this type of preparation for coping with cadaver dissection has not been studied in Spanish universities. The aim of this study is to evaluate how first-year Spanish medical students face the dissecting room and whether previous preparation about death and dying reduces the stress generated. We performed an interventional study with students who received preparatory classes before the dissection practices (Experimental Group, EG) and with students who did not (Control Group, CG). Sociodemographic data and a self-assessment on stress symptoms were collected through a questionnaire completed before and after the dissection practices. No differences were found in the self-report of symptoms of stress among students who consider themselves religious or not, or between students who had a family member in the healthcare environment or not. However, in the EG, the students who had ample experience with terminally ill patients or death reported fewer stress symptoms. Unexpectedly, the number of selfreported stress symptoms after the dissection practice was higher in EG students. In conclusion the stress levels of first-year Spanish medical students not only did not improve after receiving preparatory classes about death and dying and discussion groups, but it gets worse. We found a relationship between student stress measured and experience with terminally ill patients or death. Additional studies are needed to identify the most suitable preparation for Spanish medical students.

RESUMEN: Se han informado efectos positivos en la reducción del estrés en los estudiantes de numerosos entornos universitarios cuando se han impartido seminarios preparatorios de anatomía. Hasta la fecha, este tipo de preparación para hacer frente a la disección del cadáver no se ha estudiado en las universidades españolas. El objetivo de este estudio es evaluar cómo los estudiantes de medicina españoles de primer año se enfrentan a la sala de disección y si la preparación previa sobre la muerte y el moribundo reduce el estrés generado. Realizamos un estudio de intervención con estudiantes que recibieron clases preparatorias antes de las prácticas de disección (Grupo Experimental, GE) y con estudiantes que no las recibieron (Grupo de Control, GC). Se recogieron datos sociodemográficos y síntomas de estrés mediante un cuestionario de autoevaluación antes y después de las prácticas de disección. No se encontraron diferencias en los síntomas de estrés valorados, entre los estudiantes que se consideran religiosos y los que no, ni tampoco entre los estudiantes que tenían o no un familiar en el entorno sanitario. Sin embargo, en el GE, en los estudiantes que tenían una amplia experiencia con pacientes con enfermedades terminales o con la muerte se observaron menos síntomas de estrés. Inesperadamente, el número de síntomas de estrés recogidos después de la práctica de disección fue mayor en los estudiantes del GE. En conclusión, los niveles de estrés de los estudiantes españoles de medicina de primer año no solo no mejoraron después de recibir las clases preparatorias sobre la muerte y el moribundo y establecer grupos de discusión, sino que empeoraron. Encontramos una relación entre la medición del estrés en los estudiantes y la experiencia con pacientes con enfermedades terminales o con la muerte. Se necesitan estudios adicionales para identificar la preparación más adecuada para los estudiantes de medicina españoles.

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During routine undergraduate dissections of the upper limb, variations on the usual arterial and muscular patterns were observed in a 68 year-old male cadaver. The arterial and muscular pattern found in our specimen is similar to that of some primates in the following terms. 1) Brachial artery duplicity, on the right side, with a superficial brachio-ulnoradial artery. 2) In the right upper limb, the biceps brachii muscle continued with the superficial muscles of the forearm. 3) The brachial artery on the left side, cross over in front of the median nerve, as the only artery of the arm with a network axillary pattern. 4) On both sides, the ulnar artery was superficial and originated at the elbow from superficial brachial arteries. 5) The right anterior interosseous artery intervened in the vascularization of the hand. These results suggest that this may be a case of early detention of human embryonic development and/or the persistence of phylogenetic older patterns. In the literature, we have found no reference to the presence of all these variations in the same individual. The objective of our study was to analyze these variations from an embryological and phylogenetic perspective.

Durante las disecciones de pregrado de rutina del miembro superior, se observaron variaciones en los patrones arteriales y musculares habituales en un cadáver macho de 68 años. El patrón arterial y muscular que se encuentra en nuestro espécimen es similar al de algunos primates en los siguientes términos. 1) Duplicidad de la arteria braquial, en el lado derecho, con una arteria braquioulnoradial superficial. 2) En el miembro superior derecho, el músculo bíceps braquial continuó con los músculos superficiales del antebrazo. 3) La arteria braquial en el lado izquierdo, se cruza frente al nervio mediano, como la única arteria del brazo con un patrón axilar en red. 4) En ambos lados, la arteria ulnar era superficial y se originó en el codo de las arterias braquiales superficiales. 5) La arteria interósea anterior derecha intervino en la vascularización de la mano. Estos resultados sugieren que este puede ser un caso de detención temprana del desarrollo embrionario humano y/o la persistencia de patrones filogenéticos más antiguos. En la literatura, no hemos encontrado ninguna referencia a la presencia de todas estas variaciones en el mismo individuo. El objetivo de nuestro estudio fue analizar estas variaciones desde una perspectiva embriológica y filogenética.

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