The practice of overlapping surgery has been increasing in the delivery of orthopaedic care, aiming to provide efficient, high-quality care. However, there have been concerns about the safety of this practice. The purpose of this study is to examine safety and efficacy of a model of partially overlapping surgery that we termed “the swing room” in practice in primary hip and knee arthroplasty. A retrospective review of prospectively collected data using an administrative database was carried out on patients who underwent primary unilateral total hip and total knee arthroplasty from 2006 to 2017 at two sites of one academic center staffed by four arthroplasty surgeons. All revisions and bilateral primary procedures were excluded. Cases were stratified as overlapping or non-overlapping. Overlapping was defined when a surgeon had access to two operating rooms with two teams, and non-overlapping was defined as when a surgeon only had access to a single operating room on a particular day. Patient demographic characteristics, operating room time, procedure time, length of stay, Postoperative complications within 30 days of the procedure, unplanned hospital readmissions, unplanned reoperations, and emergency department visits were collected. The Fisher's exact Wilcoxon rank-sum test and logistic regression analysis were used for statistical analysis.Introduction
Methods
Up to 70% of the differences in human bone mass have been attributed to genetic background. These differences are associated with alterations in the biomechanical properties, micro-architecture and remodeling of bone as well as its susceptibility to fracture and its capacity for repair. In previous work it was shown that C57Bl6 mice carrying one copy of the parathyroid hormone related protein (PTHrP+/−) gene developed osteopenia by four months of age. The current study was designed to determine if the haploinsufficient phenotype was maintained on a C3H background. PTHrP+/+ and PTHrP+/− mice on C57Bl6 and C3H backgrounds were euthanised between 6 and 18 months of age. The femurs were harvested, fixed in 4% paraformaldehyde overnight and scanned on a Skyscan 1172 equipped with a 10kV X-ray source and a 10 megapixel camera at a resolution 5μm. The amount and quality of cortical and trabecular bone was quantified from 2D images and 3D reconstructions using CTAn, CTvol and CTVox software. The undecalcified specimens were embedded at low temperature in MMA, sectioned at 5 μm and stained with Von Kossa and Toluidine Blue to distinguish mineralized from unmineralized tissue.Purpose
Method
