Simultaneous extraction of two adjacent bony structures in x-ray images: Application to hip joint segmentation

Bony structure segmentation in radiographic images is an important tool for the diagnosis and treatment of orthopedic conditions. Current methods rely on the detection of single edges which often fail to correctly recover a structure´s boundary when other nearby structures are present, as is the case in the hip joint. The use of minimal paths to detect separately two adjacent edges may lead to leakage of the femoral head contour into the acetabulum´s edge due to small intensity variations and/or edge discontinuity. This article presents a new method for simultaneously detecting two adjacent edges in a radiographic image by using a novel 3D minimal path algorithm where interrelation constraints are incorporated. We apply this technique on radiographic images of hip joint in order to simultaneously extract adjacent bony contours of femoral head and acetabulum. We prove that the new algorithm improves the extraction of both contours in the region.