Hospital Resources for Pandemic Influenza

Hospital Resources for Pandemic Influenz

Cyclical aspects to twentieth century American accounting

A model of change in twentieth century American accounting is presented. The model describes three-phase cycles, each consisting of a reactive, a proactive, and synthesis phase. The text and Appendix illustrate and attempt to validate the model, and to make projections for the future

Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 1: Introduction and methodology

pre-printFusion procedures are an accepted and successful management strategy to alleviate pain and/or neurological symptoms associated with degenerative disease of the lumbar spine. In 2005, the first version of the "Guidelines for the performance of fusion procedures for degenerative disease of the lumbar spine" was published in the Journal of Neurosurgery: Spine. In an effort to incorporate evidence obtained since the original publication of these guidelines, an expert panel of neurosurgical and orthopedic spine specialists was convened in 2009. Topics reviewed were essentially identical to the original publication. Selected manuscripts from the first iteration of these guidelines as well as relevant publications between 2005 through 2011 were reviewed. Several modifications to the methodology of guideline development were adopted for the current update. In contrast to the 2005 guidelines, a 5-tiered level of evidence strategy was employed, primarily allowing a distinction between lower levels of evidence. The qualitative descriptors (standards/guidelines/options) used in the 2005 recommendations were abandoned and replaced with grades to reflect the strength of medical evidence supporting the recommendation. Recommendations that conflicted with the original publication, if present, were highlighted at the beginning of each chapter. As with the original guideline publication, the intent of this update is to provide a foundation from which an appropriate treatment strategy can be formulated

Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 16: Bone graft extenders and substitutes as an adjunct for lumbar fusion

pre-printIn an attempt to enhance the potential to achieve a solid arthrodesis and avoid the morbidity of harvesting autologous iliac crest bone (AICB) for a lumbar fusion, numerous alternatives have been investigated. The use of these fusion adjuncts has become routine despite a lack of convincing evidence demonstrating a benefit to justify added costs or potential harm. Potential alternatives to AICB include locally harvested autograft, calcium-phosphate salts, demineralized bone matrix (DBM), and the family of bone morphogenetic proteins (BMPs). In particular, no option has created greater controversy than the BMPs. A significant increase in the number of publications, particularly with respect to the BMPs, has taken place since the release of the original guidelines. Both DBM and the calciumphosphate salts have demonstrated efficacy as a graft extender or as a substitute for AICB when combined with local autograft. The use of recombinant human BMP-2 (rhBMP-2) as a substitute for AICB, when performing an interbody lumbar fusion, is considered an option since similar outcomes have been observed; however, the potential for heterotopic bone formation is a concern. The use of rhBMP-2, when combined with calcium phosphates, as a substitute for AICB, or as an extender, when used with local autograft or AICB, is also considered an option as similar fusion rates and clinical outcomes have been observed. Surgeons electing to use BMPs should be aware of a growing body of literature demonstrating unique complications associated with the use of BMPs

Cervical end of an occipitocervical fusion: a biomechanical evaluation of 3 constructs

Journal ArticleObject. Stabilization with rigid screw/rod fixation is the treatment of choice for craniocervical disorders requiring operative stabilization. The authors compare the relative immediate stiffness for occipital plate fixation in concordance with transarticular screw fixation (TASF), C-1 lateral mass and C-2 pars screw (C1L-C2P), and C-1 lateral mass and C-2 laminar screw (C1L-C2L) constructs, with and without a cross-link. Methods. Ten intact human cadaveric spines (Oc-C4) were prepared and mounted in a 7-axis spine simulator. Each specimen was precycled and then tested in the intact state for flexion/extension, lateral bending, and axial rotation. Motion was tracked using the OptoTRAK 3D tracking system. The specimens were then destabilized and instrumented with an occipital plate and TASF. The spine was tested with and without the addition of a cross-link. The C1L-C2P and C1L-C2L constructs were similarly tested. Results. All constructs demonstrated a significant increase in stiffness after instrumentation. The C1L-C2P construct was equivalent to the TASF in all moments. The C1L-C2L was significantly weaker than the C1L-C2P construct in all moments and significantly weaker than the TASF in lateral bending. The addition of a cross-link made no difference in the stiffness of any construct. Conclusions. All constructs provide significant immediate stability in the destabilized occipitocervical junction. Although the C1L-C2P construct performed best overall, the TASF was similar, and either one can be recommended. Decreased stiffness of the C1L-C2L construct might affect the success of clinical fusion. This construct should be reserved for cases in which anatomy precludes the use of the other two