E Olave

Median artery and superficial palmar branch of the radial artery in the carpal tunnel

In the carpal tunnel there are the flexor muscle tendons, their sheaths, and the median nerve. Because its walls are inflexible, any thickening of its components that reduce its area may compress the median nerve. There are many reasons for nerve compression, including persistence of the median artery into adult life. We dissected the arteries in the carpal tunnel of 102 hands of 51 adult cadavers of both sexes, age range 23-77 years, and injected latex into 42 hands. In the carpal tunnel we sought the median artery and the superficial palmar branch of the radial artery. We found the median artery in 23 of 102 cases (23%), and its calibre ranged from 0.7 to 2.7 mm, mean (SD) 1.6 (0.5) mm. In 16 cases it made up part of the superficial palmar arch. The superficial palmar branch of the radial artery was partly responsible for the distal irrigation of the hand in 48 cases (47%); and in three hands (3%) it passed through the carpal tunnel. The external diameters of these vessels were 1.8, 1.9, and 1.8 mm, respectively. These arteries might cause compression of the median nerve and consequently the carpal tunnel syndrome.

PERFORATING BRANCHES: IMPORTANT CONTRIBUTION TO THE FORMATION OF THE DORSAL METACARPAL ARTERIES

The perforating branches that originate from the deep palmar arch of the hand have been studied to provide a complete anatomical description of these vessels and assess their importance in the blood collateral pathway of the hand. We injected latex into the arteries of 50 cadaveric hands of 25 adults, of both sexes, all of Brazilian origin. These were dissected under a stereoscopic microscope. The perforating branch of the second interosseous space originated from the deep palmar arch in 80% of the cases, and it corresponded to the radial artery passing through the second space in 16%; the one of the third interosseous space originated from the deep palmar arch in 76% of the cases and from the palmar metacarpal artery of the third interosseous space in 16%; the one of the fourth interosseous space originated from the deep palmar arch in half the cases, from the deep palmar branch of the ulnar artery in 14%, and from the palmar metacarpal artery of this space in 18%. The perforating branch of the second space anastomosed with the second dorsal metacarpal artery (DMA) in 60% of the cases and formed it in 10%; the one of the third space anastomosed with the third DMA in 20% and formed it in 64%; the one of the fourth space anastomosed with the fourth DMA in 8% and formed it in 78%. These vessels are an important anastomotic pathway between the dorsal carpal network and the deep arteries of the hand and are important in the supply to the dorsum.

The deep plantar arch in humans: constitution and topography.

Abstract The integrity of the various structures within the feet depends on their blood supply. Lesions of the feet often require revascularization, which if successful avoids the need for amputation. To provide greater anatomical detail to aid vascular surgery and imaging, the anatomy and constitution of the deep plantar arch was studied in 50 adult cadaveric feet. The arteries of the foot were injected with red neoprene latex and dissected under magnification. The deep plantar arch, present in all feet, was the result of anastomosis between the deep plantar artery and the deep branch of the lateral plantar artery. The deep plantar artery was predominant in 72% of specimens (Type I arches) and the lateral plantar artery in 22% (Type II), with the contribution being equal in 6% (Type III). The medial plantar artery contributed to the medial segment of the deep plantar arch by its deep branch in 12% of specimens. The distance between the deep plantar arch and each interdigital commissure was generally constant, averaging 29% of total foot length. The deep plantar arch was located in the middle third of the foot in all specimens, being in the distal part of this third in 90%. The deep plantar arch is, therefore formed mainly by the deep plantar artery, a branch of the dorsal artery of foot its location can be estimated if foot length is known.

Innervation of the abductor digiti minimi muscle of the human foot: anatomical basis of the entrapment of the abductor digiti minimi nerve.

Abstract. The origin, relationships and innervation of the abductor digiti minimi muscle were determined in 145 human feet, from formaldehyde-fixed cadavers. The muscle arises from both processes of the calcaneal tuberosity, from the plantar aponeurosis and from the septum which separates it from the flexor digitorum brevis muscle. The nerve to the abductor digiti minimi muscle arises next to the origin of the lateral plantar nerve, close to the abductor hallucis muscle, and descends becoming closely related to the medial face of the calcaneus and the deep face of the abductor hallucis muscle. Then, it passes inferiorly through the origin of the quadratus plantae muscle and later divides into two branches for the two heads of the muscle.

Biometric study of the relationships between palmar neurovascular structures, the flexor retinaculum and the distal wrist crease

During surgical exposure of the carpal tunnel it is possible to injure the neurovascular structures closely related to the flexor retinaculum, such as the superficial palmar arch and the communicating branch between the ulnar and median nerves. Because of the importance of these structures and with the purpose of increasing knowledge of anatomical details concerning to their location, a biometric study was performed on the retinaculum and the communicating branch, and between the communicating branch and the distal wrist crease, as well as between the retinaculum and the superficial palmar arch. We dissected 56 hands from 28 Brazilian formalin‐preserved cadavers of both sexes (24 male) at the Federal University of São Paulo–Escola Paulista de Medicina, Brazil. The communicating branch was observed in 96.4% of cases and the superficial palmar arch in 78.6%. The communicating branch was found between the common palmar digital nerve of the 4th interosseous space (from the ulnar nerve) to the homonymous nerve of the 3rd interosseous space (from the median nerve). In males, the distance between the distal wrist crease and the site where the communicating branch originates from the ulnar component had an average of 33.9±5.5 mm on the right side and 30.2±8.2 mm on the left. The distance between the distal wrist crease and the junction of the communicating branch with the common palmar digital nerve of the 3rd interosseous space was 43.6±6.9 mm on the right and 40.2±6.2 mm on the left side. Conversely, in 14.8% of cases (1 female), the communicating branch was observed to emerge from the common palmar digital nerve of the 3rd interosseous space. The distance between the retinaculum and the superficial palmar arch in the axial line of the 4th metacarpal bone was on average 7.3±4.3 mm on the right and 8.3±3.5 mm on the left side. At the same level, the distance between the retinaculum and the communicating branch was 6.2±3.7 mm on the right side and 5.1±2.8 mm on the left. These results can be used as a reference during surgical procedures in the palmar region.

The ulnar tunnel: a rare disposition of its contents

The ulnar tunnel is located at the proximal part of the hand radial to the pisiform bone and to the proximal part of the carpal tunnel. Inside it lie the ulnar nerve and artery. Compression of the ulnar nerve in this tunnel is often reported. Cysts, occupational trauma, fractures and muscle variations are among the main causes (Schjelderup, 1964; Kleinert & Hayes, 1971). Damage to the ulnar nerve and artery during the endoscopic decompression of the carpal tunnel has been reported recently (Agee et al. 1992; Nath et al. 1993; De Smets & Fabry, 1995). The structures within the ulnar tunnel are closely related to the medial part of the flexor retinaculum, in particular the ulnar artery which is located lateral to the ulnar nerve. During a study of this region we found a rare disposition of the contents of this tunnel. We believe that knowledge of this variation is important for the surgical anatomy of this region.

Trayecto del nervio gluteo inferior asociado a la división alta del nervio isquiático

El nervio gluteo inferior, ramo del plexo sacro, abandona la pelvis pasando generalmente por debajo del musculo piriforme. De este plexo se origina tambien el nervio isquiatico, el cual puede presentar variaciones en su relacion con el musculo mencionado, entre ellas, las que se refieren a la division alta del mismo. Sin embargo, son escasos los trabajos que correlacionen esta division con el trayecto del nervio gluteo inferior y su relacion con el musculo piriforme. Con el proposito de verificar una posible asociacion entre los trayectos de estos nervios, fueron disecadas 80 regiones gluteas de cadaveres de individuos brasilenos adultos en el Departamento de Morfologia de la Universidade Federal de Sao Paulo. Se encontraron dos tipos de variacion entre el nervio isquiatico y el musculo piriforme: en 9 casos (11,2 %) el nervio fibular comun paso a traves del musculo y el nervio tibial transcurrio por debajo de su margen inferior (Tipo I); en dos casos (2,5 %), correspondientes a un mismo individuo, el nervio fibular comun hizo su trayecto por sobre el margen superior del musculo piriforme y el nervio tibial paso por debajo de su margen inferior (Tipo II). En el tipo I, el nervio gluteo inferior paso a traves del musculo en 6 casos y en los 3 restantes una parte del nervio perforo al musculo y la otra paso por debajo de su margen inferior; en el tipo II, el nervio gluteo inferior transcurrio por debajo del margen inferior del musculo en uno de los casos y en el otro, una parte de este nervio se origino del nervio fibular comun y la otra, paso por debajo del margen inferior del musculo. El trayecto del nervio gluteo inferior a traves del musculo piriforme podria estar relacionado con la atrofia glutea observada en los pacientes con sindrome del musculo piriforme

Aspectos Clínicos y Morfológicos de los Dientes Supernumerarios

La hiperdoncia es una anomalia dentaria de causa desconocida, caracterizada por el aumento del numero de dientes. Ocurre con mayor frecuencia en la maxila, de preferencia en el sexo masculino, siendo mas comun en la denticion permanente. La presencia de dientes supernumerarios puede ser responsable por alteraciones en la denticion permanente, como por ejemplo, el atraso en la erupcion y dislocamientos. Ademas, el paciente puede presentar oclusion anormal, reabsorcion de dientes adyacentes y formacion de quistes. El presente articulo describe en un paciente de sexo masculino, de 9 anos de edad, la presencia de dos incisivos laterales superiores derechos y un incisivo lateral superior izquierdo, permanentes, parcialmente erupcionados. El examen radiologico revelo un segundo incisivo lateral superior izquierdo, no erupcionado. Se debe resaltar que tanto en la zona de la pieza 1.2 como en la 2.2, los dientes presentaron anatomia normal y no el aspecto conoide comunmente observado en los dientes supernumerarios. En nuestro caso, con el proposito de efectuar tratamiento de ortodoncia, fue indicado extraccion quirurgica de los dientes mencionados.

Estudio topográfico y biométrico del ganglio cervicotorácico (ganglio estrellado)

El tronco simpatico consiste en una serie de ganglios unidos por cordones interpuestos que se extienden a lo largo de las caras laterales de la columna vertebral, desde la base del craneo hasta el coccix y se divide en porciones cervical, toracica , abdominal y pelvica. Generalmente presenta de 21 a 25 ganglios de tamanos variables y recibe fibras nerviosas de la porcion toracolumbar. Se analizaron 100 troncos simpaticos de cadaveres formolizados de individuos brasilenos, adultos, de ambos sexos. El ganglio cervicotoracico se observo en 70 % de los casos, presentandose en 75,7 % de estos constituido por la union del ganglio cervical inferior con el primer ganglio toracico; fue fusiforme (44,2 %) o irregular (44,2 %). El ganglio tuvo de promedio 18,0 mm en sentido craneocaudal; 5,3 mm en sentido laterolateral y 3,7 mm en sentido anteroposterior. Se constato que su forma y localizacion es variable, pero con un conocimiento detallado de las relaciones topograficas y biometricas de esta estructura, se puede abordar quirurgicamente la region de transicion cervicotoracica con seguridad

Arterias renales múltiples

El conocimiento de las variaciones de la irrigacion renal es de mucha importancia debido al incremento de transplantes renales y cirugias de reconstruccion vascular. La literatura muestra que generalmente hay una arteria renal para cada rinon, sin embargo pueden observarse variaciones de origen y de numero. Presentamos dos casos de arterias renales triples izquierdas, en muestras pertenecientes a la Unidad de Anatomia de la Facultad de Ciencias de la Salud, Universidad Catolica del Maule, Talca. En uno de los casos, el origen de la arteria renal R1 (superior) se efectuo a nivel de la parte inferior del origen de la arteria mesenterica superior, la que despues de un trayecto de 30 mm se dividio en dos ramas menores de calibre similar, que ingresaron en el hilio renal por delante de la vena renal. La rama R2 (media) se origino 4 mm distal a la anterior, correspondiendo a una rama posterior que tambien ingreso en el hilio; la rama R3 (inferior) lo hizo 23 mm distal a la R2. Esta ultima penetro en el rinon inmediatamente por debajo de la incisura del seno renal. En el segundo caso, hay diferencias con respecto al anterior, ya que la rama R1 y la R3 penetraron en el hilio renal, en cambio la R2 tiene un trayecto descendente y penetra de forma similar al R3 del caso anterior. El conocimiento de estas arterias multiples es necesario y es de importancia consideraR1as durante la intervenciones quirurgicas que involucren a este organo