RESUMO
Transversus abdominis plane (TAP) is a fascial plane containing the thoracolumbar nerve branches that innervate the abdominal wall. Limited information is available on the anatomical organization of these nerve branches in the dog, which is of great importance for the success of the TAP block anaesthetic technique. The aim of this study was to describe the origin and conformation of thoracolumbar nerves running through the TAP in 20 hemi-abdominal walls of 10 adult mongrel dog cadavers with an average body weight of 12.6 kg (range: 9.6-15.6). The abdominal walls were dissected from superficial to deep direction, the skin and both obliquus externus abdominis and obliquus internus abdominis muscles were dissected and reflected dorsally to expose the transversus abdominis muscle and the thoracolumbar nerve branches located in this plane. The anatomical features of ventral nerve branches were described. The thoracic nerve branches: T7-T12 and costoabdominalis; and the lumbar nerve branches: iliohypogastricus cranialis, iliohypogastricus caudalis, ilioinguinalis and cutaneus femoris lateralis were identified in all the cadavers. Anatomical variations related to the presence or absence within the TAP of the T7, T8 and T9 nerve branches were found. These variations should be taken into account when planning the TAP block technique in dogs.
Assuntos
Músculos Abdominais/inervação , Cães/anatomia & histologia , Vértebras Lombares/inervação , Nervos Torácicos/anatomia & histologia , Animais , Cadáver , Feminino , MasculinoRESUMO
STUDY DESIGN: An ex vivo histologic study in rabbits. OBJECTIVE: To evaluate the early histologic effects of polymethylmethacrylate (PMMA) injection on bone and intraosseous neural tissue following vertebroplasty in rabbit lumbar vertebrae. SUMMARY OF BACKGROUND DATA: Vertebroplasty with PMMA is performed to treat painful osteoporotic vertebral fractures. Early pain relief has been consistently documented, but its mechanism has not been elucidated. Among the mechanisms of pain relief may be the immediate stabilizing effects of the cement, and the exothermic reaction during curing, which may lead to intraosseous neural ablation. It has been well established that PMMA can induce thermal osteonecrosis after arthroplasty, but the potential for osteonecrosis after vertebroplasty has not been established. Previous studies have suggested that temperature elevations during cement curing may induce thermal bone necrosis. However, this cause-and-effect relationship has not yet been histologically studied in an animal model. METHODS: Vertebroplasty with PMMA was performed at 2 levels in 12 New Zealand rabbits (24 levels); trochar insertion without PMMA injection was performed at 3 levels each of 2 control animals (6 levels). Sacrifice was performed 24 hours after the procedure. Histologic examination was performed to evaluate the presence of bone or intraosseous neural tissue necrosis. RESULTS: Half of the levels with PMMA showed evidence of necrosis at the bone-cement interface. Almost all (11 of 12) showed only focal necrosis, with only 1 specimen showing necrosis along the entire periphery of the PMMA. The other 12 specimens and all control levels displayed no bone necrosis. There was no evidence of intraosseous neural tissue necrosis in control or PMMA-injected specimens. CONCLUSION: Injection of PMMA in rabbit lumbar vertebral bodies produces early, focal bone necrosis in only half of cases, suggesting that competency of the cement-bone interface is reasonable in most cases. No evidence of intraosseous neural tissue damage was found.
Assuntos
Vértebras Lombares/efeitos dos fármacos , Osteonecrose/induzido quimicamente , Polimetil Metacrilato/efeitos adversos , Vertebroplastia/métodos , Animais , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/inervação , Masculino , Modelos Animais , Tecido Nervoso/efeitos dos fármacos , Tecido Nervoso/patologia , Osteócitos/efeitos dos fármacos , Osteócitos/patologia , Osteonecrose/patologia , Polimetil Metacrilato/administração & dosagem , Coelhos , RadiografiaRESUMO
Se realizó un trabajo de investigación clínica en población de edad pediátrica atendida en un Hospital de Ortopedia, la cual requirió de tratamiento quirúrgico en miembros inferiores y para el logro del mismo se administró anestesia regional del tipo de bloqueo caudal, el cual fue estudiado, en cuanto a dos posiciones: Sims modificada (decúbito lateral y una de las extremidades flexionadas) y la posición genupectoral. El resto del método las dosis y concentraciones fueron similares en ambos grupos. Los resultados mostraron que la posición de Sims es la que permitió mayor altura metamérica.