ABSTRACT
During routine dissection in the Department of Anatomy, multiple variations of forearm muscles in relation to the radial nerve and its branches were observed on the right side of a 34 year old male cadaver. Brachioradialis close to its origin was receiving muscle fibers from the brachialis and the radial nerve was passing in between them. Extensor carpi radialis brevis was absent and the extensor carpi radialis longus was giving two tendons in the second compartment of extensor retinaculum before its insertion while passing deep to the abductor pollicis longus. Absence of extensor carpi radialis brevis can be explained with the arrangement in lower mammals, where the two extensores carpi radiales are represented by one muscle. Ontogeny repeats phylogeny and anatomical variations have developmental basis. Henee, the pattern of muscular arrangement in this case can be said to be less evolved than the usual arrangement. The course of radial nerve between the two heads of brachioradialis makes it highly vulnerable to compression and injury, which may manifest as wrist drop (radial nerve palsy) or radial tunnel syndrome (compression of posterior interosseous nerve).
Durante una disección de rutina en el Departamento de Anatomía, se observaron múltiples variaciones de los músculos del antebrazo, en relación con el nervio radial y sus ramos, en el lado derecho de un cadáver de 34 años de edad, de sexo masculino. Cerca de su origen el músculo braquioradial recibía fibras del músculo braquial y el nervio radial cruzaba entre ellos. El músculo extensor radial corto del carpo se encontraba ausente y el músculo extensor radial largo del carpo se continuaba con dos tendones en el segundo compartimiento del retináculo extensor, bajo el músculo abductor largo de pulgar, antes de su inserción. La ausencia del músculo extensor radial corto del carpo se puede explicar en mamíferos inferiores, donde los dos músculos extensores radiales están representados por un sólo músculo. La ontogenia repite la filogenia y las variaciones anatómicas inciden en su desarrollo. Por lo tanto, de acuerdo al patrón muscular se puede afirmar que en este caso existe menos evolución que lo habitual. El curso del nervio radial entre las dos cabezas del músculo braquioradial, lo hace muy vulnerable a la compresión y las lesiones, que pueden manifestarse son, caída de la muñeca (parálisis del nervio radial) o el síndrome del túnel radial (compresión del nervio interóseo posterior).
Subject(s)
Humans , Male , Adult , Forearm/innervation , Muscle, Skeletal/innervation , Radial Nerve/anatomy & histology , Cadaver , Radial Nerve/abnormalitiesABSTRACT
OBJECTIVE: The tendons of the extensor carpi radialis longus and brevis muscles are quite useful in tendon transfer, such as in correction of finger clawing and restoration of thumb opposition. Knowledge of additional radial wrist extensor muscle bellies with independent tendons is useful in the above-mentioned surgical procedures. METHODS: The skin, subcutaneous tissue, and antebrachial fascia of 48 (24 on the right side and 24 on left side) male upper limb forearms were dissected. The following aspects were then analyzed: (a) the presence of additional muscle bellies of radial wrist extensors, (b) the origin and insertion of the additional muscle, and (c) measurements of the muscle bellies and their tendons. RESULTS: Five out of 48 upper limbs (10.41 percent) had additional radial wrist extensors; this occurred in 3 out of 24 left upper limbs (12.5 percent) and 2 out of 24 right upper limbs (8.3 percent). In one of the right upper limbs, two additional muscles were found. The length and width of each additional muscle belly and its tendon ranged between 2 - 15cm by 0.35 - 6.4cm and 2.8 - 20.8cm by 0.2 0.5cm, respectively. The additional radial wrist extensor tendons in our study basically originated either from the extensor carpi radialis longus or brevis muscles and were inserted at the base of the 2nd or 3rd metacarpal bone. CONCLUSION: The present study will inform surgeons about the different varieties of additional radial wrist extensors and the frequency of their occurrence.
Subject(s)
Aged , Humans , Male , Middle Aged , Forearm/anatomy & histology , Muscle, Skeletal/anatomy & histology , Wrist/anatomy & histology , Cadaver , Tendons/anatomy & histologyABSTRACT
To evaluate the mandibular angle and to analyze the relationship of the angle and height & breadth of the ramus of the mandible to the gender, so as to study its role in the anthropological diagnosis. The angle, height and breadth of the ramus of adult dry human mandibles of both sexes were measured using a goniometer. The values obtained were analyzed statistically. The present study showed a statistically significant difference in the mandibular angle as well as height of the ramus between both the sexes. The mean mandibular angle of Indian population when compared to that of European population was found to be lower by 9 degrees. The findings of this study might be useful in providing anthropological data that can also be used in dental and medical practice. However, the Indian mandible can be used for sexual dimorphism as is usual in anthropological work; it appears to possess important unfavourable anatomic factors that may predispose the individuals to difficult laryngoscopy or intubation.
Para estudiar su rol en el diagnóstico antropológico, evaluamos el ángulo de la mandíbula y analizamos las relaciones de este ángulo con la altura y ancho de la rama de la mandíbula, en ambos sexos. Con un goniómetro, en huesos secos, fue obtenido el ángulo, alto y ancho de las mandíbulas humanas. Los valores obtenidos fueron analizados estadísticamente. El estudio mostró diferencias estadísticamente significativas en el ángulo mandibular como también en la altura de la rama de la mandíbula, en ambos sexos. La media del ángulo mandibular de la población hindú fue 9 grados menor, comparada con la población europea. Los resultados de este estudio pueden ser útiles al aportar datos antropológicos utilizados en las prácticas médica y dental. Por otra parte, la mandíbula de los hindúes puede ser usada como dimorfismo sexual como es usual en trabajos antropológicos. Parece haber factores anatómicos desfavorabes importantes que pueden predisponer a los individuos a laringoscopías difíciles o intubación.
Subject(s)
Humans , Male , Female , Mandible/anatomy & histology , Sex Characteristics , India , Population Groups , Sex FactorsABSTRACT
Tibial collateral ligament by virtue of its length, composite attachments, and biomechanical exertions is more prone to lesions. A systematic analysis of the dimensions and variations of this ligament has been presented in this article. With the decrease emphasis on anatomy as a preclinical subject and recent successful moves to curtail total teaching hours for dissection, coupled with the increasing shortage of cadavers, data of this nature will in our opinion becomes scarce progressively. With these factors in context, and attempt is made to record the gross morphological features of the ligament from a series of dissections.
El ligamento colateral tibial, por virtud de su longitud, inserciones y esfuerzos biomecánicos, está más propenso a lesiones. Un análisis sistemático de las dimensiones y variaciones de este ligamento se presentan en este artículo. El decrecimiento del énfasis de la Anatomía como un ramo preclínico y la falta de cadáveres nos movieron a disminuir las horas de disección. Así, en nuestra opinión, los datos anatómicos son progresivamente más escasos. Con el propósito de registrar las características morfológicas macroscópicas del ligamento colateral tibial, realizamos una serie de disecciones.