Meta-analysis of pre-clinical studies of early decompression in acute spinal cord injury:a battle of time and pressure

The use of early decompression in the management of acute spinal cord injury (SCI) remains contentious despite many pre-clinical studies demonstrating benefits and a small number of supportive clinical studies. Although the pre-clinical literature favours the concept of early decompression, translation is hindered by uncertainties regarding overall treatment efficacy and timing of decompression.We performed meta-analysis to examine the pre-clinical literature on acute decompression of the injured spinal cord. Three databases were utilised; PubMed, ISI Web of Science and Embase. Our inclusion criteria consisted of (i) the reporting of efficacy of decompression at various time intervals (ii) number of animals and (iii) the mean outcome and variance in each group. Random effects meta-analysis was used and the impact of study design characteristics assessed with meta-regression.Overall, decompression improved behavioural outcome by 35.1% (95%CI 27.4-42.8; I(2)=94%, p<0.001). Measures to minimise bias were not routinely reported with blinding associated with a smaller but still significant benefit. Publication bias likely also contributed to an overestimation of efficacy. Meta-regression demonstrated a number of factors affecting outcome, notably compressive pressure and duration (adjusted r(2)=0.204, p<0.002), with increased pressure and longer durations of compression associated with smaller treatment effects. Plotting the compressive pressure against the duration of compression resulting in paraplegia in individual studies revealed a power law relationship; high compressive forces quickly resulted in paraplegia, while low compressive forces accompanying canal narrowing resulted in paresis over many hours.These data suggest early decompression improves neurobehavioural deficits in animal models of SCI. Although much of the literature had limited internal validity, benefit was maintained across high quality studies. The close relationship of compressive pressure to the rate of development of severe neurological injury suggests that pressure local to the site of injury might be a useful parameter determining the urgency of decompression

Cyclooxygenase-2 inhibition delays the attainment of peak woven bone formation following four-point bending in the rat

Fracture healing is retarded in the presence of cyclooxygenase-2 (COX-2) inhibitors, demonstrating an important role of COX-2 in trauma-induced woven bone adaptation. The aim of this experiment was to determine the influence of COX-2 inhibition on the remodeling and consolidation of non-traumatic woven bone produced by mechanical loading. A periosteal woven bone callus was initiated in the right tibia of female Wistar rats following a single bout of four-point-bending, applied as a haversine wave for 300 cycles at a frequency of 2Hz and a magnitude of 65N. Daily injections of Vehicle (VEH: polyethyleneglycol) or the COX-2 inhibitor, DFU (2.0 mg.kg-1 and 0.02mg.kg-1 i.p.), commenced 7 days postloading, and tibiae were examined 2, 3, 4 and 5 weeks postloading. Tibiae were dissected, embedded in polymethylmethacrylate and sectioned for histomorphometric analysis of periosteal woven bone. No significant difference in peak woven bone area was observed between DFU-treated and VEH rats. But treatment with DFU resulted in a temporal defect in woven bone formation, where the achievement of peak woven bone area was delayed by one week. Woven bone remodeling was observed in DFU-treated rats at 21 days post-loading, demonstrating that remodeling of the periosteal callus is not prevented in the presence of a COX-2 inhibitor in the rat. We conclude that COX-2 inhibition does not significantly disrupt the mechanism of woven bone remodeling, but alters its timing

Influência da extensão da artrodese lombossacra nos resultados clínicos e funcionais Influencia de la extensión de la artrodesis lumbosacra en los resultados clínicos y funcionales Influence of the extent of lumbosacral arthrodesis in clinical and functional outcomes

OBJETIVO: Verificar a influência da extensão da fusão póstero-lateral lombossacra e seu impacto nos resultados clínicos e funcionais. MÉTODOS: Foram avaliados 22 pacientes portadores de estenose central, foraminal ou hérnia de disco lombar, associadas a instabilidade segmentar, submetidos ao tratamento cirúrgico para a descompressão neural e artrodese póstero-lateral. Os pacientes foram divididos em dois grupos, de acordo com quantidade de níveis artrodesados: Grupo 1: fusão em um nível e Grupo 2: fusão em dois ou mais níveis. Os pacientes preencheram questionários referentes ao acompanhamento pós-operatório (uso de medicamentos analgésicos e satisfação com o tratamento) e escala analógica visual de dor lombar e ciática. Além disto, foram aplicados os questionários Oswestry e SF-36 para avaliação da qualidade de vida. RESULTADOS: Os resultados do SF-36 mostraram bons níveis de qualidade de vida em ambos os grupos, com exceção do domínio "Aspectos Físicos". Não houve correlação significativa entre a extensão da artrodese e os desfechos clínicos. CONCLUSÕES: Os pacientes submetidos à artrodese póstero-lateral apresentaram qualidade de vida satisfatória, exceto pela diminuição da aptidão física. Entretanto, o maior número de níveis artrodesados não teve impacto negativo sobre os aspectos clínicos e funcionais.<br>OBJETIVO: Investigar la influencia del grado de la fusión posterolateral lumbosacral y su impacto en los resultados clínicos y funcionales. MÉTODOS: Se evaluaron 22 pacientes con estenosis central, foraminal o hernia de disco lumbar, asociadas a inestabilidad segmentaria; se sometieron a cirugía para la descompresión neural y la artrodesis posterolateral. Los pacientes fueron divididos en dos grupos según el número de niveles fusionados: Grupo 1: la fusión en un nivel, y Grupo 2: la fusión en dos o más niveles. Los pacientes completaron cuestionarios sobre seguimiento posoperatorio (uso de medicamentos analgésicos y satisfacción con el tratamiento) y la escala analógica visual para el dolor lumbar y la ciática. Por otra parte, se aplicaran los cuestionarios Oswestry y SF-36 para evaluar la calidad de vida. RESULTADOS: El SF-36 mostró resultados de buenos niveles de calidad de vida en ambos grupos, excepto en el campo "Aspectos Físicos". No hubo correlación significativa entre la magnitud de la artrodesis y los resultados clínicos. CONCLUSIONES: Los pacientes que fueron sometidos a artrodesis posterolateral mostraron calidad de vida satisfactoria, con excepción de disminución de la aptitud física. Sin embargo, el mayor número de niveles fusionados no tuvo un impacto negativo en los aspectos clínicos y funcionales.<br>OBJECTIVE: Investigate the influence of the extent of posterolateral lumbosacral fusion and its impact on clinical and functional results. METHODS: We evaluated 22 patients with central or foraminal stenosis or lumbar disc herniation associated with segmental instability that underwent to surgery for nerve decompression and posterolateral arthrodesis. Patients were divided into two groups according to the number of levels fused: Group 1: fusion at one level and Group 2: fusion of two or more levels. Patients completed questionnaires regarding postoperative follow-up (use of analgesic medications and treatment satisfaction) and visual analog scale for lumbar pain and sciatica. Moreover, the questionnaires Oswestry and SF-36 were administered to assess quality of life. RESULTS: SF-36 showed good levels of quality of life in both groups, except the field "Physical Aspects". There was no significant correlation between the extent of the arthrodesis and clinical outcomes. CONCLUSIONS: Patients who underwent posterolateral arthrodesis showed satisfactory quality of life, except for a decrease of physical fitness. However, the higher number of levels fused did not have negative impact on clinical and functional aspects

Acesso anterior para pacientes com fraturas traumáticas do tipo compressão do segmento toracolombar (T11 a L2) da coluna vertebral Anterior approach in patients with traumatic compression fracture type of thoracolumbar spine (T11-L2)

OBJETIVO: Relatar a experiência com o acesso anterior em fraturas traumáticas do tipo compressão no segmento toracolombar (T11 a L2) que foram submetidos à cirurgia pelo acesso anterior. MÉTODO: Estudo prospectivo de janeiro de 1994 a janeiro de 2004 envolvendo 32 pacientes. A presença da fusão óssea e do alinhamento foram analisadas 6 e 12 meses após a cirurgia. RESULTADOS: A idade média foi 36,53 anos, sendo 23 do sexo masculino. A vértebra mais atingida foi L1 (n=12). A maioria dos casos que internaram em ASIA/IMSOP C (n=10) e D (n=13) evoluiram para ASIA/IMSOP E. A média da deformidade angular pré-operatória foi 14,9&deg;&plusmn;7,5&deg;, com diferença estatística (p<0,0001) na comparação com o valor encontrado no pós-operatório de 30 dias. CONCLUSÃO: A via anterior permite melhor descompressão do canal e uma correção da deformidade angular superior à observada pela via posterior isolada.<br>OBJECTIVE: To describe experience with anterior access in compression fractures of thoracolumbar segment (T11 to L2) traumatic fractures that undergone anterior access surgery. METHOD: A prospective study was conducted between January 1994 and January 2004 with 32 patients. The bone fusion and thoracolumbar alignment were analyzed 6 months and 12 months after the surgery. RESULTS:The average age was 36.53 years old with 23 male patients. The most compromised vertebrae was L1 (n=12). The 23 patients that was ASIA/IMSOP C and ASIA/IMSOP D turned to ASIA/IMSOP E after 1 month (n=12) and 12 months (n=5) of surgery. The preoperative angular deformity average was 14.9&deg;&plusmn;7.5&deg;. Statistical significance was found (p<0.0001) when compared to the 30 days postoperative value. CONCLUSION: The anterior access permits a better spinal canal decompression and angular deformity correction when compared with the posterior access alone