Abstract
Patients, and their femurs, come in all shapes, sizes, and types. Fortunately, so do cementless femoral stems! A simple approach is to separately consider A) the part inside the bone and B) the part outside the bone. The inner-cortical geometry (Dorr type), bone density, and presence of any deformity, influence selection of stem shape, length, and extent of ingrowth surface (the part inside the bone). Restoration of limb length and offset is a function of the neck angle and length (the part outside the bone). Clinical data indicates that undersizing of cementless stems increases the risk of revision for aseptic loosening while restoration of limb length and offset favorably affects patient satisfaction and function.
