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The goniometer is a reasonable and simple clinical tool, but for research protocols, we suggest using the radiographic method because of the higher level of precision required.

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This paper presents an in vivo validation of a method for the three-dimensional (3-D) high-resolution modeling of the human spine, rib cage, and pelvis for the study of spinal deformities. The method uses an adaptation of a standard close-range photogrammetry method called direct linear transformation to reconstruct the 3-D coordinates of anatomical landmarks from three radiographic images of the subject's trunk. It then deforms in 3-D 1-mm-resolution anatomical primitives (reference bones) obtained by serial computed tomography-scan reconstruction of a dry specimen. The free-form deformation is calculated using dual kriging equations. In vivo validation of this method on 40 scoliotic vertebrae gives an overall accuracy of 3.3 +/- 3.8 mm, making it an adequate tool for clinical studies and mechanical analysis purposes.

Agile methods have taken software development by storm but have been primarily applied to projects in what is referred to as the “agile sweet spot,” which consists of small collocated teams working on small, non-critical, green field, in-house software projects with stable architectures and simple governance rules. These methods are being used more and more on large projects, but little documentation is available in the academic literature. This article investigates the adoption and adaptation of agile methods for use on large projects in large organizations. The empirical study is based first on case studies, followed by a survey to validate and enrich the case study results. The results are somewhat paradoxical in that some features are common to almost all observations, whereas others show extreme variability. The common features include use of Scrum methodology and agile coaches, as well as the non-respect of the agile principle of emergent architecture.

This article addresses the research question: How is uncertainty affecting project portfolios managed in dynamic environments? The management of four portfolios was studied in two large multidivisional corporations. The portfolios were characterized by a high degree of uncertainty and many interdependencies between the projects. The results of this research indicate that the sources of change go beyond the two groups identified in The PMI Standard for Portfolio Management (Project Management Institute, 2006), that is, (a) Portfolio Performance and (b) Business Strategy Changes. The sensing mechanisms put in place by both companies primarily addressed uncertainty related to project scope.

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Scoliosis is a three-dimensional deformation of the spine that can be treated by vertebral fusion using surgical instrumentation. However, the optimal configuration of instrumentation remains controversial. Simulating the surgical maneuvers with personalized biomechanical models may provide an analytical tool to determine instrumentation configuration during the pre-operative planning. Finite element models used in surgical simulations display convergence difficulties as a result of discontinuities and stiffness differences between elements. A kinetic model using flexible mechanisms has been developed to address this problem, and this study presents its use in the simulation of Cotrel -Dubousset Horizon surgical maneuvers. The model of the spine is composed of rigid bodies corresponding to the thoracic and lumbar vertebrae, and flexible elements representing the intervertebral structures. The model was personalized to the geometry of three scoliotic patients (with a thoracic Cobb angle of 458, 498 and 398). Binary joints and kinematic constraints were used to represent the rod-implant-vertebra joints. The correction procedure was simulated using three steps: (1) Translation of hooks and screws on the first rod; (2) 908 rod rotation; (3) Hooks and screws look-up on the rod. After the simulation, slight differences of 0 -68 were found for the thoracic spine scoliosis and the kyphosis, and of 1-88 for the axial rotation of the apical vertebra and for the orientation of the plane of maximum deformity, compared to the real post-operative shape of the patient. Reaction loads at the vertebra-implant link were mostly below 1000 N, while reaction loads at the boundary conditions (representing the overall action of the surgeon) were in the range 7 -470 N and maximum torque applied to the rod was 1.8 Nm. This kinetic modeling approach using flexible mechanisms provided a realistic representation of the surgical maneuvers. It may offer a tool to predict spinal geometry correction and assist in the preoperative planning of surgical instrumentation of the scoliotic spine.