Papillary muscles of left ventricle—Morphological variations and it’s clinical relevance

Introduction The two left ventricular papillary muscles are small structures at sternocostal and inferior wall but are vital to mitral valve competence. Extra papillary muscles could be found. Partial or complete rupture, complicating acute myocardial infarction, causes severe or even catastrophic mitral regurgitation, potentially correctable by surgery. Detailed knowledge of normal anatomy and variations is vital for accurate interpretation of information by echocardiography and for surgical repair. Materials and methods The material for present study consisted of 52 formalin fixed adult apparently normal cadaveric hearts belonging to either sex obtained from the Department of Anatomy. These hearts were dissected carefully to open the left ventricle and to expose the papillary muscles. According to their attitudinal position they were described as supero-lateral (S-L) and inferoseptal muscle (I-S) instead of conventional anterolateral and posteromedial. Different morphological features of papillary muscles were noted and measurements were taken. Results Classical picture of left ventricular papillary muscle was found only in 25% cases. Additionally extra muscles were found 34.61% and 71.15% in S-L and I-S group, respectively. Different shapes and pattern of papillary muscles were also been identified. An additional attribute of this study was measurement of length and breadth of papillary muscles which thus provides a base line data for further detailed studies in a large scale. Conclusion Oriental nomenclature is necessary not only for anatomist but also for electrocardiographers. Breadth of papillay muscle should be taken into morphometric account as for screening of hypertrophic cardiomyopathy. Proper anatomical knowledge is crucial for clinicians, surgeons and radiologists.

Two rare anatomical variations of external jugular vein: an embryological overview / Dos raras variaciones anatómicas de la vena yugular externa: una visión embriológica

Human anatomy is an ocean of unending variations and its mysteries are being unravelled since ages. Knowledge of variations in the superficial veins of head and neck is essential to carry out successful surgical procedures. During routine dissection of head and neck of two middle aged male cadavers, in the Department of Anatomy, Calcutta National Medical College, Kolkata, India, we came out with some interesting venous architecture. The retromandibular vein on the left side of both the cadavers was found to be undivided and joined with the facial vein in the neck at an acute angle to form a common venous trunk at variable distances from the angle of the mandible. That trunk ultimately drained into the left subclavian vein. This might be the result of disappearance of the cephalic part of the external jugular vein and formation of an additional communication between common facial vein and the external jugular vein in foetal life. In one case, we also came across an extra transverse communication between that common trunk and the internal jugular vein. A detail of those cases with embryological explanation is attempted...

La anatomía humana tiene un sin fin de variaciones y sus misterios se han develado desde el inicio de los tiempos. El conocimiento de las variaciones anatómicas de las venas superficiales de la cabeza y del cuello es fundamental para llevar a cabo con éxito los procedimientos quirúrgicos. Durante una disección de rutina de cabeza y cuello encontramos una arquitectura venosa interesante en dos cadáveres de hombres de mediana edad en el Departamento de Anatomía de la Facultad de Medicina Nacional Calcuta, Calcuta, India. En el lado izquierdo del cuello de ambos cadáveres, la vena retromandibular no se encontraba dividida, y se unía a la vena facial en un ángulo agudo, para formar un tronco venoso común a una distancia variable desde el ángulo de la mandíbula. Ese tronco finalmente drenaba en la vena subclavia izquierda. Esto podría ser el resultado de la desaparición de la parte cefálica de la vena yugular externa y la formación de una comunicación adicional entre la vena facial común y la vena yugular externa en la vida fetal. En un caso, también se encontró con una comunicación adicional transversal entre ese tronco común y la vena yugular interna. Se realiza una descripción en detalle de los casos junto a una explicación embriológica...

Unilateral quadripartite composition of pectoral major muscle: anatomical description and clinical implications / Composición unilateral cuadripartita del músculo pectoral mayor: descripción anatómica e implicancias clínicas

A unilateral anomalous disposition of the muscular slips of pectoralis major was observed in an adult male cadaver during routine gross anatomy teaching session. The pectoralis major muscle displayed unusual configuration and comprised of four parts delineated by three intramuscular clefts. Further, the sternocostal part was found to divide into two fasciculi. The origin and insertion of pectoralis major muscle was as usual and unremarkable. Interestingly, the innervation of the muscle was observed to bear an important variation. The clavicular and sternocostal slips of pectoralis major muscle received a direct branch from the lateral cord of brachial plexus in addition to its usual innervation from the lateral and medial pectoral nerves. The multiplicity of innervation of pectoralis major as encountered in the present study would presumably augment its suitability for its use in reconstructive procedures. An additional anomalous attachment of the pectoralis minor muscle was also observed emanating from the second rib, apart from the usual third, fourth and fifth ribs. These variants of the pectoral muscles may also have implications in biomechanical studies, as they may alter the kinematics.

Una disposición anómala unilateral de los vientres musculares del músculo pectoral mayor se observó en un cadáver adulto de sexo masculino durante una clase de rutina de anatomía. El músculo pectoral mayor mostró una configuración inusual y presentaba cuatro partes delimitadas por tres depresiones intramusculares. Además, la parte esternocostal se encontraba dividdida en dos fascículos. El origen y la inserción del músculo pectoral mayor era normal. Curiosamente, la inervación de los músculos, presentaba una importante variación anatómica. Los fascículos clavicular y esternocostal del músculo pectoral mayor recibieron una rama directa del fascículo lateral del plexo braquial, además de su inervación normal de los nervios pectoral lateral y medial. La múltiple inervación del músculo pectoral mayor como se encuentró en el presente estudio, probablemente, haga aumentar su idoneidad para el uso en procedimientos reconstructivos. También se observó un fascículo adjunto anómalo adicional del músculo pectoral menor, que se originaba de la segunda costilla, además de su origen en la tercera, cuarta y quinta costillas. Estas variaciones de los músculos pectorales también puede tener implicancias en estudios biomecánicos, ya que probablemente alteran la cinemática.