Sihler's Staining of the Thoracic Cutaneous Nerve and its Significance / Tinción de Sihler del Nervio Cutáneo Torácico y su Relevancia

SUMMARY: Our team has modified Sihler's intramuscular nerve staining method to allow for calculation of nerve density. Therefore, this study aimed to show the overall distribution pattern of the thoracic cutaneous nerves to provide a morphological basis for selecting and matching sensory reconstruction during skin flap transplantation. Twelve Chinese adult cadavers were dissected; the thoracic skin was removed, and the modified Sihler's staining method was performed. Centered around the nipple, the chest skin was divided into four regions: medial-superior, lateral-superior, lateral-inferior, and medial-inferior. The thoracic skin was not only innervated by the branches of the 1st to 7th intercostal and supraclavicular nerves, but also by a small number of nerves that directly reached the skin and passed through the pectoralis major muscle. There is a phenomenon of cross overlap between the branches of adjacent intercostal nerves. The branches of the 2nd to 7th intercostal nerves were distributed in the breast, and the branches of the lateral and anterior cutaneous branches were densely distributed around the nipple, forming a grid-like anastomosis. There was no cross-overlapping innervation between the anterior cutaneous branches on both sides. The density of nerve distribution in the four regions of the chest was in the order of the medial-superior, lateral-superior, lateral-inferior and medial-inferior region, respectively. These results may be used to map sensory regions when designing thoracic skin flaps for reconstruction surgery to obtain improved sensory recovery.

Nuestro equipo ha modificado el método de tinción nerviosa intramuscular de Sihler para permitir el cálculo de la densidad nerviosa. Por lo tanto, este estudio tuvo como objetivo mostrar el patrón de distribución general de los nervios cutáneos torácicos proporcionando una base morfológica para seleccionar y combinar la reconstrucción sensorial durante el trasplante de colgajo de piel. Se diseccionaron 12 cadáveres de individuos adultos chinos. Se eliminó la piel torácica y se realizó el método de tinción de Sihler modificado, centrada alrededor del pezón, la piel del pecho se dividió en cuatro regiones: medial- superior, lateral-superior, lateral-inferior y medial-inferior. La piel torácica no solo estaba inervada por los ramos de los nervios intercostal y supraclavicular 1º a 7º, sino también por un pequeño número de nervios que llegaban directamente a la piel y pasaban a través del músculo pectoral mayor. Existe un fenómeno de superposición cruzada entre los ramos de los nervios intercostales adyacentes. Los ramos de los nervios intercostales 2º a 7º se distribuyeron en la mama, y los ramos de los ramos cutáneos lateral y anterior se distribuyeron densamente alrededor del pezón, formando una anastomosis en forma de rejilla. No hubo inervación cruzada entre los ramos cutáneos anteriores en ambos lados. La densidad de la distribución nerviosa en las cuatro regiones del tórax estaba en el orden de región medial-superior, lateral-superior, lateral-inferior y medial-inferior, respectivamente. Estos resultados pueden ser útiles para mapear regiones sensoriales al diseñar colgajos de piel torácicos para utilizarlos en cirugía de reconstrucción y obtener así una mejor recuperación sensorial.

Advances in pharmacological research of sanshool / 中国药理学通报

The pericarp of Zanthoxylum bungeanum Maxim. (Rutaceae) is a traditional Chinese herbal medicine with many therapeutic effects such as antipruritic, analgesic and insecticidal effects. In recent years, various studies have revealed sanshool as the main bioactive ingredient of Zanthoxylum bungeanum Maxim. It can bind to a variety of ion channels and receptors, exerting wide-ranging biological and pharmacological activities including analgesic effects, intestinal protection, hypoglycemic effects and other effects. The relevant pharmacokinetics, drug targets and pharmacological effects were reviewed in this paper to provide a reference for the systematic research of sanshool and the development of new drugs.

Estructuras neurovasculares en riesgo durante abordajes artroscópicos en tobillo: un estudio cadavérico / Neurovascular structures at risk during arthroscopic approaches to the ankle: a cadaveric study

La artroscopía de tobillo ha tenido un aumento en su utilización en las últimas tres décadas para la corrección quirúrgica de afecciones del tobillo. Se prefiere a la cirugía abierta por sus múltiples ventajas, destacando la disminución de las complicaciones, con una prevalencia de 7,3 % para la artroscopia y 15,9 % para la cirugía abierta. Estudios previos de artroscopia de tobillo reportan complicaciones generales entre el 0,9 a 17 %, de las cuales el 33 a 50 % envuelven los nervios cutáneos, principalmente el nervio fibular superficial o alguna de sus ramas. El objetivo del presente estudio fue determinar estructuras neurovasculares en riesgo próximas a los portales artroscópicos del tobillo descritos en la literatura. Se llevó a cabo un estudio anatómico observacional, transversal y descriptivo. La muestra consistió en 10 tobillos de población mexicana en los cuales se introdujeron cánulas artroscópicas en algunos portales de tobillo descritos en la literatura y se realizó una disección superficial de los pies, posteriormente se determinó la distancia entre las estructuras neurovasculares próximas a los portales y se realizó un análisis estadístico con los resultados. Los resultados del estudio anatómico evidenció que portal antero-medial es el portal más seguro debido a que la distancia de dicho portal a una estructura neurovascular fue la más elevada, obteniendo una media de 11,30 mm±11,25, la menor distancia encontrada fue la del portal postero-medial con una media de 2,84 mm±1,28. El 10 % de los portales laterales resultaron con lesión de estructuras venosas tributarias de la vena safena menor. El portal antero-medial es el portal más seguro pero con mayor variabilidad respecto a las distancias de las estructuras neurovasculares al portal y el portal postero-medial es el de mayor riesgo debido a la mayor presencia de estructuras neurovasculares.

In the last three decades the procedure of ankle arthroscopy has increased in ankle surgery. It is preferred to open surgery for multiple reasons, the most important is that it has fewer complications, with a prevalence of 7.3 % for arthroscopy and 15.9 % for open surgery. Previous studies of ankle arthroscopy reported general complications between 0.9 to 17 % which involved cutaneous nerves at a rate of 33 to 50 %, mainly the superficial peroneal nerve. The principal objective of this study was to determine the neurovascular structures near the arthroscopic portals of the ankle. We carried out anatomical, observational, transversal and descriptive studies. This study was performed with 10 ankles of Mexican population. A 4 mm trocar was introduced in some of the portals described in the literature and superficial dissection of the feet was made. Subsequently, the distance between the nearest neurovascular structures was measured, and statistical analysis of the results was realized. The results of the anatomic study was that the anterior-medial portal was considered the safest portal because it has the highest distance between the portal and the neurovascular structure, with an average of 11.30 mm±11.25, the posterior-medial portal has the smallest average with 2.84 mm±1.28. A lesion of the small saphenous vein was reported in 10 % of the lateral portals. The antero-medial portal is the safest but with highest variability regarding the distances of the neurovascular structures to the portal and the postero-medial portal has the highest risk due to the increased presence of neurovascular structures.

An Unusual Branching Pattern of the Median Cubital Vein and its Relations with Lateral Cutaneous Nerve of Forearm in the Upper Extremity: Anatomicoclinical Notes

Cubital fossa is the usual site for performing venepuncture in the clinical settings for health screenings and diagnostic purposes. This procedure is simple and uncomplicated but occasionally can lead to bleeding and pain in the form of complex regional pain syndrome. Superficial veins of the upper limb are often used for venepuncture for transfusion purposes and for obtaining blood samples. These veins are also used for cardiac catheterisation and giving intravenous injections. During routine cadaveric dissection, a cubital venous variation was observed in a 45-yr –old, male cadaver. The median cubital vein initiated from cephalic vein passed upwards and laterally superficial to posterior branch of medial cutaneous nerve of forearm. In the middle of its course, it gave off an ascending channel which further divided into medial and lateral tributaries. The medial tributary terminated into the basilic vein, whereas the lateral tributary ascended laterally superficial to a branch of lateral cutaneous nerve of forearm and drained into cephalic vein at the level of elbow joint. Various patterns of superficial cubital veins have been mentioned in literature. Awareness of such anatomical variations is crucial while performing venepuncture in clinical settings as well as for creating arteriovenous fistulas for hemodialysis purpose.

Innervation of free anterolateral thigh flap for repairing widespreadly traumatic soft tissue defects in heel / 中华显微外科杂志

Objective To explore new methods of innervating the anterolateral thigh flap(ALTF) for repairing widespreadly traumatic soft tissue defects in heel and report their initial results of clinical application. Methods Twenty-five consecutive ALTFs were transplanted in 25 patients for repairing widespreadly traumatic soft tissue defects in heel from October 2005 to October 2010. Three ways were used in this series for sensory reconstruction of ALTFs,which based on the primary researches of the anatomic and histomorphological characteristics of lateral femoral cutaneous nerve (LFCN),medial calcaneal nerve (MCN) and lateral calcaneal nerve (LCN). The first way which was of suture between reshaped LFCN and MCN or LCN was used in 16 cases, the second way which was of perineurial suture combined with epineurial suture was used in 6 cases,and the small-gap-suture way was used in the remaining cases.The section of LFCN 5-7 cm below the anterior superior iliae spine and the initial segment of MCN or LCN were selected as anastomotic position. Postoperative follow-up parameters include pain sensation, touch sensation, thermal sensibility and static two-point discrimination. Results All flaps survived,and the wounds were primary intention.Twentyfive cases followed up 9-36 months (18 months on average).All flaps restored protective sensation,and the rate of good sensory recovery was 60％. All patients restored weighing and walking, and no ulceration happened. Conclusion Satisfactory sensory function restoration can be obtained by paying attention to the distribution and variety of LFCNs, selecting suitable cutaneous nerves and rational coaptated position as well as suitable suturation means which based on the anatomic and histomorphologieal characteristics of LFCN,MCN and LCN when repairing widespread soft tissue defects in heel.

División Alta del Nervio Fibular Superficial: Origen Precoz de los Nervios Cutáneos Dorsales del Pie / High Division of Superficial Fibular Nerve: Early Origin of the Dorsal Cutaneous Nerves of the Foot

Los nervios cutáneos dorsales del pie se originan a partir del nervio fibular superficial (NFS), después que éste pasa desde el compartimiento lateral de la pierna a través de la fascia profunda, para luego distribuirse superficialmente en el dorso del pie. A veces, el nervio fibular superficial se divide precozmente, por lo que estos nervios se originan profundamente y con una disposición diferente. Con el propósito de dar a conocer en estos casos, los niveles de origen de los nervios cutáneos dorsales del pie y el punto de penetración en la fascia profunda de la pierna, se estudiaron 16 muestras de individuos, chilenos, adultos, fijadas en formaldehido al 10 por ciento. En 2 de ellas, su origen se observó a un nivel alto, cerca de la parte proximal de la fíbula. En el primer caso, el nervio cutáneo dorsal intermedio se originó directamente de la división posterior del NFS; la división anterior del NFS se subdividió en dos ramos, los que después de un corto trayecto se unieron y formaron el nervio cutáneo dorsal medial. En el segundo caso, los nervios cutáneos dorsales intermedio y medial se originaron directamente del NFS, que después de un corto trayecto se dividió en estos dos nervios. El origen de los nervios cutáneos dorsales del pie se registró en relación al epicóndilo lateral del fémur y el paso de éstos a través de la fascia profunda de la pierna hacia su distribución cutánea fue relacionado al maléolo lateral. Aunque el origen de los nervios cutáneos dorsales del pie ocurra a un nivel próximo a la cabeza de la fíbula, perforan la fascia mencionada, en su tercio distal. Un conocimiento detallado del NFS y de sus ramos y variaciones anatómicas puede reducir lesiones iatrogénicas en éstos durante los procedimientos quirúrgicos realizados en el compartimiento lateral de la pierna.

The dorsal cutaneous nerves of the foot originate from the superficial fibular nerve (SFN), then pass from the lateral compartment of the leg piercing the deep fascia, thus distributed superficially in the dorsum of the foot. Sometimes SFN splits early, so these nerves originate deeply and with a different arrangement. The objective of this research was to study in these cases, the origin of the dorsal cutaneous nerves of the foot and pierce point level in the deep fascia of the leg. We studied 16 formolized samples of Chilean adult individuals. In two of them its origin was observed at a high level, near the proximal epiphysis of the fibula. In the first case the intermediate dorsal cutaneous nerve arose directly from the posterior division of SFN, of short course; the anterior division of SFN was subdivided into two branches, which after a short course, both branches joined to form the medial dorsal cutaneous nerve. In the second case the medial and intermediate dorsal cutaneous nerves originated directly from the SFN, which after a short course, it divided in these two nerves. The origin level was recorded in relation to the lateral epicondyle of the femur and the passage of these nerves through the deep fascia of the leg for its skin distribution was located in relation to the lateral malleolus. Although the origin of the dorsal cutaneous nerves of the foot occur very close to the proximal epiphysis of the fibula, passing through the mentioned fascia in its distal third. A detailed knowledge of the branches of the SFN and variations can reduce injuries in these nerves during surgical procedures in the lateral compartment of the leg.