Mangala M. Pai

Anatomical organization of aortic arch variations in the India: embryological basis and review

OBJETIVOS: Determinar a porcentagem e o tipo de variacoes do arco aortico em individuos indianos, bem como sua importância clinica e cirurgica e base embriologica. PACIENTES E METODOS: Em nossa investigacao, os padroes de ramificacao do arco aortico foram estudados em 62 cadaveres fixados em formalina de ambos os sexos, de origem indiana e com idade entre 45 e 79 anos. As dissecacoes foram realizadas em cadaveres preservados em formalina, e as variacoes do arco aortico foram observadas apos a exposicao das regioes toracica e cervical durante a dissecacao de rotina de alunos da graduacao do Kasturba Medical College, Mangalore, India. RESULTADOS: O arco aortico normal de tres ramificacoes foi encontrado em 56 cadaveres (91,4%); as variacoes foram encontradas em seis cadaveres (9,6%); 4,8% apresentavam origem comum das arterias carotidas; 1,6% tinham sequencia binominada, e o mesmo especime tinha a origem da arteria coronaria esquerda diretamente no arco aortico; 1,6% apresentavam a origem da arteria subclavia direita diretamente na aorta; 1,6% tinham como ramificacao do arco aortico uma arteria vertebral esquerda. Cinco de seis cadaveres com padrao de ramificacao anomalo do arco aortico eram do sexo feminino. Um cadaver do sexo masculino apresentou origem anomala da arteria vertebral esquerda diretamente no arco. CONCLUSAO: O amplo espectro de variacoes nos padroes anatomicos das ramificacoes do arco aortico na populacao indiana estava em concordância com outras populacoes mundiais. Embora as origens anomalas das ramificacoes do arco aortico sejam meramente variacoes anatomicas, informacoes precisas sobre elas e essencial para a cirurgia vascular na regiao do torax, cabeca e pescoco.

The accessory heads of flexor pollicis longus and flexor digitorum profundus: Incidence and morphology

Kiloh–Nevin syndrome caused by compressive neuropathy of the anterior interosseous nerve in the forearm is believed to occur because of its compression by the accessory head of flexor pollicis longus (FPLah). Gantzer described two accessory muscles, the more frequent is the FPLah and the less frequently observed is the flexor digitorum profundus accessory head (FDPah). Many studies have reported the prevalence, origin, insertion, nerve supply, and relations of these accessory muscles, most of them focusing on the FPLah. This study was designed to investigate the prevalence, morphology, relation to median and anterior interosseous nerve, and also the coexistence of both the accessory heads. A total of 126 upper limbs of the embalmed cadavers were examined in this study. Fifty‐eight limbs (46.03%) showed the presence of the FPLah and 18 limbs (14.28%) had the FDPah. The most common origin of both the accessory muscle bellies was from the under surface of the flexor digitorum superficialis. The FPLah inserted into the FPL muscle at varying levels with 80% inserting into the proximal third of FPL, whereas the FDPah in all cases ended near the level of the wrist joining with one or more tendons of the FDP. Clinical implication of the variation is discussed. Clin. Anat. 21:252–258, 2008.

Pterygospinous bar and foramina in Indian skulls: incidence and phylogenetic significance

Incomplete or complete ossification of the pterygospinous ligament is uncommon. Entrapment of mandibular nerve and its branches was reported due to this anatomical variation, when found. The aim of the present study is to investigate the incidence of the pterygospinous bony bridges in Indian dry skulls. A total of 416 adult dry skulls of Indian origin were studied. In 9.61% of the samples the pterygospinous bony bars were found, out of which 5.76% was complete and 3.84% was incomplete. Such variations are of clinical significance while dealing with mandibular nerve and its branches and various clinical symptoms related to it.

A rare case of bilateral sternocleidomastoid muscle variation

An abnormal sternocleidomastoid (SCM) muscle was encountered bilaterally during routine dissection of the head and neck region of a 60 year old male cadaver. The SCM muscle of both the sides had an additional sternal head arising from the capsule of the sternoclavicular joint and the supero-lateral border of the manubrium sterni. The clinical significance of the present variation is immense, as it might cause difficulty in assessing the vital neurovascular structures of the neck during surgical procedure.

Morphological and topographical anatomy of nutrient foramina in the lower limb long bones and its clinical importance

BACKGROUND Knowledge regarding nutrient foramina of bones is useful in surgical procedures such as microvascular bone transfer in order to preserve the circulation. The objective of the present study was to study the morphology and topography of nutrient foramina and to determine the foraminal index of the lower limb long bones to provide detailed data on such features. METHOD The study comprised examination of 206 lower limb long bones which included femora, tibiae and fibulae. The nutrient foramina were identified analysed macroscopically and the foramen index calculated. Each bone was divided into five parts and topographical analysis was performed on each section. RESULTS Femora had single nutrient foramen in 47.7% of the cases, double foramen in 44.2% of the cases, triple in 3.5% of the cases and an absence of foramen in 4.6%. In the case of tibiae, 98.6% showed single foramen and in 1.4% of the cases, the foramen was absent. With respect to fibulae, 90.2% had single foramen and foramen was absent in 9.8%. The mean foraminal index was 38.9 for the femora, 32.5 for tibiae and 49.2 for fibulae. The majority (51.3%) of the foramina in the femora were located at the 2/5(th) part, 98.3% of the tibiae foramina at the 2/5(th) part and 60% of the fibulae at the 3/5(th) part. CONCLUSION The study provides information on the morphology and topography of nutrient foramina in lower limb long bones. The double foramina were more common in femur and rare in the tibia and fibula. The foramina of the femur and tibia were commonly observed at their upper part, whereas in the fibula they were present on the lower part. This knowledge of the nutrient foramina has to be kept in mind during surgical procedures.

Accessory neurovascular foramina on the lingual surface of mandible: Incidence, topography, and clinical implications

CONTEXT It was suggested that the accessory neurovascular foramina of the mandible might be of significance in relation to the effectiveness of local anesthesia following the routine inferior alveolar nerve block. AIMS To investigate the incidence of neurovascular foramina over the lingual surface of the mandible in South Indian population. SETTINGS AND DESIGN The study was conducted at the department of anatomy. MATERIALS AND METHODS The study included 67 human adult dry mandibles, the exact ages and sexes of which were not known. The location and number of neurovascular foramina were topographically analyzed. STATISTICAL ANALYSIS USED Descriptive statistics. RESULTS The foramina were observed in 64 mandibles (95.5%) and were often multiple in most of the cases. They were located between the two medial incisors in 8 mandibles (1.9%), between the medial and lateral incisor in 34 mandibles (50.7%; 25-bilateral; 7-right; 2-left), between the lateral incisor and canine in 7 mandibles (10.4%; 2-bilateral; 3-right; 2-left), between the canine and first premolar in 6 cases (8.9%; 3 on each side). Foramina were also present around the genial tubercle in 56 mandibles (83.6%). Among them, 52 mandibles showed a single foramen just above the genial tubercle, 34 mandibles had foramina below the tubercles, 13 mandibles had foramina on the right side of genial tubercle and 17 were having on the left side. CONCLUSION Since the anatomical details of these foramina are important to various fields of dentistry and oncology, the present investigation was undertaken. The clinical significance and implications are emphasized.

An Anomalous Left External Jugular Vein Draining into Right Subclavian Vein: A Case Report

El conocimiento de los diferentes patrones de drenaje de las venas superficiales de la cabeza y cuello, en particular, las venas yugulares no solo son importantes para anatomistas, sino tambien para los cirujanos que operan a este nivel y para los medicos en general. Las variaciones son importantes tambien para los radiologos intervencionistas, quienes realizan procedimientos transyugulares, asi como implantaciones portales y portosistemicas transyugulares intrahepaticas o derivacion venosa selectiva. Resultados de estudios recientes informan que la venas superficiales, especialmente la vena yugular externa, es cada vez mas utilizada para la canulacion en diagnosticos y procedimientos terapeuticos. Se reporta una muy inusual variacion anatomica de la vena yugular externa del lado izquierdo, presente en un cadaver embalsamado de sexo masculino. Fueron realizadas evaluaciones embriologicas de la anomalia y se compararon con la literatura mostrando que se trata de una variacion rara.

Hypoplastic posterior tibial artery and the enlarged peroneal artery supplying the posterior crural region: a rare variation

Variacoes arteriais de partes distais dos membros inferiores estao bem documentadas e podem ser demonstradas com o auxilio de ultra-sonografia Doppler ou por arteriografia. Entretanto, a ausencia ou variacao da arteria tibial posterior e um raro achado. Apresentamos um caso de arteria tibial posterior hipoplasica que terminava suprindo o musculo solear. Esse suprimento arterial variante foi fornecido pela arteria peroneal aumentada que continuava como arteria plantar lateral. Estar consciente dessas variacoes e importante para cirurgioes vasculares ao realizarem reconstrucoes arteriais em procedimentos de derivacao femorodistal, bem como para ortopedistas durante correcao cirurgica do pe torto.

Morphological study of styloid process of the temporal bone and its clinical implications

The objective of this study was to study the morphometry of the styloid process of temporal bone and prevalence of elongated styloid process. The morphology of elongated styloid process along with its embryological and clinical importance are discussed. The present study included 110 human dry skulls which were procured from the bone collections of the department of anatomy. The styloid process was observed macroscopically on both sides of all the skulls, the elongations if any were noted. All the styloids were measured for their length, thickness at different levels and interstyloid distance at various levels. Out of 110 specimens, only 5 skulls (4.5%) exhibited the elongated styloid process. Among them, 3 skulls (2.7%) had unilateral elongation and 2 skulls (1.8%) had bilateral elongation of the styloid process. The mean length of the styloid process was 17.8±9.3 mm and 18.2±5.6 mm for the right and left sides, respectively. The prevalence of elongated styloid process in the present study was 4.5%. The clinical anatomy of this congenital variant is important to the neurosurgeon and radiologist, while interpreting the computed tomogram and magnetic resonance image scans. The morphological knowledge of elongated styloid process is clinically important since the course of the vertebral artery may be distorted in such situations.

The Subclavius Posticus Muscle: its Phylogenetic Retention and Clinical Relevance

Durante una diseccion de rutina, un musculo supernumerario fue encontrado en el lado derecho de la region infraclavicular de una cadaver de sexo masculino. Este musculo se originaba de la superficie superior de la primera costilla y cartilago costal y se insertaba en un grueso ligamento que se extendia desde la parte medial de la incisura supraescapular a la capsula de la articulacion acromioclavicular. Este musculo estaba inervado por un ramo del nervio subclavio. De acuerdo a su localizacion e inervacion el musculo aberrante fue considerado como el musculo subclavio posticus. Las relaciones anatomicas del musculo tienen significancia clinica