The exemplary embodiments of the present disclosure are described and illustrated below to encompass methods and devices for designing patient specific prosthetic cutting jigs and, more specifically, to devices and methods for segmenting bone of the knee and the resulting cutting guides themselves. Moreover, the present disclosure relates to systems and methods for manufacturing customized surgical devices, more specifically, the present disclosure relates to automated systems and methods of arthroplasty cutting guides, systems and methods for image segmentation in generating computer models of knee joint.