RESUMO
A popliteal nerve block may be used to provide anesthesia and extended analgesia of the lower extremity, to ameliorate severe and long lasting postoperative pain. The aim of this study was to elucidate the anatomical location of tibial (TN) and common peroneal (CPN) nerves in the popliteal crease for effective nerve block. Fifty fresh specimens from 27 adult Chinese cadavers (16 males and 11 females, age range from 35 to 87 years) were investigated. Twenty-two cadavers were used to identify nerve locations and 5 cadavers were used to determine the depths of nerves in cross section. TN was found to be located at 50% from the most lateral point of the popliteal crease at 1.4 cm deep to the surface. In 20% of the 50 specimens, the medial sural cutaneous nerve branched out below or at the popliteal crease, whereas the CPN was located at 26.0% from the most lateral point of the popliteal crease and at 0.7 cm deep to the surface. Furthermore, in 6.0% of specimens the lateral sural cutaneous nerve branched out below or at the popliteal crease. This study suggests that the TN and CPN leave the sciatic nerve at variable distances from the popliteal crease. However, we believe that the results of the present study about the location of TN and CPN at the popliteal crease offer a good guide to optimal nerve block.
El bloqueo nervioso poplíteo puede ser utilizado para proporcionar anestesia y analgesia prolongada del miembro inferior y para aliviar el dolor postoperatorio severo y duradero. El objetivo fue determinar la localización anatómica de los nervios tibial (NT) y fibular común (NFC) en el pliegue poplíteo para un bloqueo nervioso efectivo. Se utilizaron 50 miembros inferiores frescos pertenecientes a 27 cadáveres adultos chinos (16 hombres y 11 mujeres, rango de edad entre 35-87 años). Se utilizaron 22 cadáveres para identificar la localización de los nervios y los 5 restantes para determinar la profundidad de los nervios en una sección transversal. El NT se encontró en el 50% de los casos desde el punto más lateral del pliegue poplíteo a 1,4 cm de la superficie. En el 20% de 50 muestras, el nervio cutáneo sural medial se ramificó por debajo o en el pliegue poplíteo, mientras que el NFC se encontró en el 26% de los casos desde el punto más lateral del pliegue poplíteo a 0,7 cm de la superficie. Además, en el 6% de las muestras, el nervio cutáneo sural lateral se ramificó por debajo o en el pliegue poplíteo. Nuestros resultados sugieren que el NT y NFC emergen del nervio ciático a distancias variables del pliegue poplíteo. Creemos que los resultados sobre la ubicación de NT y NFC en el pliegue poplíteo ofrecen una buena guía para el adecuado bloqueo nervioso.
Assuntos
Humanos , Masculino , Adulto , Nervo Tibial/anatomia & histologia , Fíbula/inervação , Bloqueio Nervoso , CadáverRESUMO
To isolate stem-like cells from the human MG-63 osteosarcoma cell line, different subpopulations of MG-63 cells were cloned by limiting dilution and passaged to obtain different sublines. The subline with highest clonogenicity was identified using a proliferation assay, cell-cycle analysis, and soft-agar colony-forming assay. The sublines were further selected in serum-free medium containing 20 ng/ml vincristine to identify cells that could form suspended sarcospheres. Identified cells were then characterized based on morphology, cell surface markers, adipogenic and osteogenic differentiation, and tumorigenicity in nude mice. A total of 19 holoclones that could be stably passaged were obtained. Sublines A1, A3, and D1 were markedly different from other sublines and the parental cell line. Subline D1 not only had a higher colony-forming efficiency and formed larger colonies, but also possessed a shorter latency of tumorigenesis in vivo. After subline D1 was cultured in suspension in medium containing vincristine, a highly enriched subpopulation of cells that could form sarcospheres and be stably passaged were obtained. These cells, designated as MG-63-M expressed multiple markers of multipotent or embryonic stem cells and possessed the capacity for self-renewal, multilineage differentiation, and significant multi-drug resistance. Thus, our results suggest that a subpopulation of stem-like cells can be isolated from human MG-63 osteosarcoma cell line.