Effective botulinum toxin injection guide for treatment of cervical dystonia.

The aim of this study was to elucidate the distribution of the accessory nerve within the sternocleidomastoid muscle (SCM) to aid identifying the optimum sites for botulinum neurotoxin (BoNT) injections and applying chemical neurolysis. Thirty SCM specimens from 15 Korean cadavers were used in this study. Sihler's staining was applied to 10 of the SCM specimens. Transverse lines were drawn in 20 sections to divide the SCM into 10 divisions vertically, and a vertical line was drawn into the medial and lateral halves from the mastoid process to the sternoclavicular joint. The most densely innervated areas were 5/10-6/10 and 6/10-7/10 along the lateral and medial parts of the muscle, respectively. We suggest injecting BoNT in the medial region 6/10-7/10 along the SCM prior to injecting in the lateral region 5/10-6/10 along the muscle to ensure safe and effective treatment. Clin. Anat. 33:192-198, 2020. © 2019 Wiley Periodicals, Inc.

Demonstration of intramuscular artery and nerve distribution in the same whole mount gracilis muscle by different colors / Demostración de la distribución intramuscular de la arteria y nervio del músculo grácil mediante diferentes colores

The goal of this study was to describe the intramuscular artery and nerve distribution in detail by different colors in the same whole mount gracilis muscle. Red latex injection into the external iliac artery was performed on 14 fresh human cadavers. Two weeks later, 28 gracilis muscles were harvested from the cadavers and during this course the number of the arterial pedicle of each specimen was counted. Then, the muscle specimens were fixed in 10 % formalin 4 weeks for fixation and Sihler's staining procedures was performed on each muscle specimens. After all of the procedures, the gracilis muscle appeared almost transparent, and the extra- and intramuscular artery and nerve branches, even the terminals, were clearly demonstrated in red and dark blue separately. Two of the 28 specimens were supplied by a single main arterial pedicle alone, 14 specimens by a main arterial pedicle and an accessory pedicle, 8 specimens by a main pedicle and 2 accessory pedicles, while 4 specimens by a main arterial pedicle and 3 accessory pedicles. Although the number of the arterial pedicles was inconsistent, the intramuscular artery branches anastomosed with each other and formed a whole arterial system in all specimens. The nerve innervating the gracilis muscle divided into two or three major branches, which directed distally and innervated the distal two thirds of the muscle, while running longitudinally and parallel to the muscle fibers. We found the innervation pattern was remarkably consistent from specimen to specimen. This study provided very detailed and useful information for anatomists, physiologists and reconstructive surgeons. Furthermore, we here also provided a new method to demonstrate the intramuscular artery and nerve distribution in the same whole mount muscle by different colors for other researchers to refer to.

El objetivo de este estudio fue describir en detalle la distribución intramuscular de la arteria y el nervio del músculo grácil por diferentes colores en un solo montaje. Se realizó inyección de látex rojo en la arteria ilíaca externa en 14 cadáveres humanos frescos. Dos semanas más tarde se retiraron 28 músculos grácil de los cadáveres y se realizó un conteo del número de pedículos arteriales de cada muestra. Las muestras de músculo se fijaron en formalina al 10 % durante 4 semanas para los procedimientos de tinción de Sihler. Al término de todos los procedimientos, el músculo grácil parecía casi transparente, y las ramas extra e intramusculares de las arterias y los nervios, incluso los terminales, se observaron en azul y rojo oscuro por separado. Dos de los 28 especímenes presentaron por pedículo arterial principal único, 14 muestras un pedículo arterial principal y un pedículo accesorio, 8 de las muestras un pedículo principal y dos pedículos accesorios, mientras que 4 muestras un pedículo arterial principal y tres pedículos accesorios. Aunque el número de los pedículos arteriales era inconsistente, las ramas de la arteria intramuscular se anastomosaban entre sí y formaban un sistema arterial conjunto en todos los especímenes. El nervio que inerva el músculo grácil se encontró dividido en dos o tres ramos principales, dirigidos distalmente e inervaron los dos tercios distales del músculo, mientras que otro discurre longitudinalmente y en paralelo a las fibras musculares. Encontramos que el patrón de inervación fue notablemente consistente de un espécimen a otro. Este estudio proporciona información muy detallada y útil para los anatomistas, fisiólogos y cirujanos. Además, también se proporcionó un método innovador para demostrar la distribución intramuscular de la arteria y el nervio en un mismo músculo, entero, y con diferentes colores.