Biomechanical Flexion–Extension Forces in Normal Canine Lumbosacral Cadaver Specimens Before and After Dorsal Laminectomy–Discectomy and Pedicle Screw–Rod Fixation

Abstract

Dorsal laminectomy and partial discectomy does not lead to significant spinal instability. Pedicle screw-rod fixation of L7 and S1 may be used to stabilize an unstable L7-S1 junction in dogs with degenerative lumbosacral stenosis.

Bir Köpekte Travmatik Torakal İnstabilitenin Pediküllü Vida Rod Fiksasyon Sistemiyle Tedavisi

“…The aim of the PSRFS is to improve deformity and stabilize the spine in its natural position until fusion has occurred and prevent further degenerative changes [7,9] . In veterinary literatures, PSRFS has been only used to stabilize lumbosacral region after laminectomy for treatment of degenerative lumbosacral stenosis in dogs [10,11,14,15] . Furthermore, the system was used to investigate fusion in lumbar vertebrae [16] .…”

“…The screws were applied to the corpus vertebra of According to the perioperative observation rigid fixation was achieved, even though one level instrumentation. Meij et al [14] reported that dorsal laminectomy and partial discectomy had changed the stiffness characteristics of the spine specimen in neutral zone without changing range of motion, however, in natural cases with degenerative lumbosacral stenosis laminectomy and discectomy could decrease stiffness significantly in vivo. In the case the stiffness of the vertebral region was markedly decreased after discectomy and removal of fractured end plate.…”

“…The use of pedicle screws for adult humans led to fracture of the lateral and the medial wall of the pedicle. Pedicle screws for pediatric patients better fit for adult canine vertebral pedicle [14] . The pediatric pedicle screws which is Ø 3.5 mm diameter were successfully used for the dog in this case and it was determined that pediatric PSPFS systems are suitable for large breed dogs…”

Uso do Clamp and Rod Internal Fixation pedicular na estabilização da coluna lombossacra em felino: relato de caso

“…Essas características observadas durante o procedimento cirúrgico no caso referido corroboram com Tomlinson (2005), o qual afirma que as principais propriedade do CRIF incluem excelente versatilidade, boa capacidade de contorno (retorcimento), facilidade de aplicação, mínima instrumentação e mínimo contato ósseo, além de ser financeiramente acessível e de força suficiente para permitir carga de peso imediata. No caso relatado, os parafusos foram aplicados exclusivamente nos pedículos vertebrais, no entanto poderia ter sido feita a aplicação dos parafusos envolvendo especificamente os pedículos e os corpos vertebrais de L7 e do sacro, o que possivelmente confere maior rigidez e resistência ao sistema, conforme relataram Meij et al (2007), quando utilizaram parafusos pediculares na coluna lombossacra. Segundo Smolders et al (2012), uma fixação lombossacra em corredores seguros deve ser realizada dorsocaudolateralmente para ventrocraniomedialmente, ou seja, proveniente da cortical dorsal da lâmina até a cortical dorsal do corpo vertebral, sem perfurar a porção cortical ventral assim como as paredes medial e lateral do pedículo.…”

Biomechanical assessment of the effects of decompressive surgery in non-chondrodystrophic and chondrodystrophic canine multisegmented lumbar spines

“…Specimens were prepared and tested as described previously [13]. Immediately after euthanasia, the spinal specimens were harvested.…”