A spherical reamer comprises at least two cutting elements having a support member and at least one circumference cutting member built on it. The cutting member can be characterized by edge configuration, geometric parameters or further by positional parameters, respectively. All variations of the parameters above lead various types of the cutting elements and methods of assembling either reusable or disposable reamer including self-assembling or/and “One Size Cutting Element for Assembling Several Size of Reamers” in order to fit into the application need in the field.