In this paper we introduce a new stable mathematical model for locating and measuring the medial axis of geometric objects, called the quadratic multiscale medial axis map of scale λ, and provide a sharp regularity result for the squared-distance function to any closed nonempty subset K of Rn. Our results exploit properties of the function Cl λ(dist 2(·; K)) obtained by applying the quadratic l...

Case: A 63 year-old woman with bilateral severe medial knee osteoarthritis, huge cartilaginous defects, and severe varus-valgus instability was treated by tibial condylar valgus (TCV) osteotomy. Her preoperative point of the weight-bearing (mechanical) axis was right -19% and left -20%. After surgery, the mechanical axis was right 60% and left 61% with a high degree of patient satisfaction. Con...

PURPOSE Femoral osteochondritis dissecans (OCD) is a disorder of unknown aetiology and variable prognosis that causes knee pain. In this paper, the authors study the impact of lower limb malalignment on the development and prognosis of OCD. METHODS After anteroposterior (AP) and lateral radiograph and MRI of the knee, 53 cases of OCD were diagnosed. All patients were studied by standing full-...

We describe a region-based shape representation that might be particularly useful from a biological perspective because it promotes the localization of objects, and object parts relative to each other. The proposed medial-point representation is similar to medial-axis type representations, but it is more compact. The medial points are those points along the medial axis that are equidistant from...

We propose the triangulation axis as an alternative skeletal structure for a simple polygon P . This axis is a straight-line tree that can be interpreted as an anisotropic medial axis of P , where inscribed disks are line segments or triangles. The underlying triangulation that specifies the anisotropy can be varied, to adapt the axis so as to reflect predominant geometrical and topological fea...