Femoral bone loss in total hip arthroplasty: classification and preoperative planning.

A single comprehensive classification system that can adequately describe all types of bone loss associated with hip arthroplasty should become a standard for reporting purposes. There is a need for a critical appraisal of the classification systems currently in use and, through a consensus, for development of a system that will permit comparison between the reported results of different techniques. Although no one classification system is ideal, the one proposed by the AAOS Committee on the Hip is the most comprehensive and the most consistently used. It addresses not only revision total hip arthroplasty but also primary hip replacement. It also addresses other conditions related to problems with the bone stock, such as those resulting from a previous hip arthrodesis on the acetabular side and femoral stenosis and malalignment on the femoral side. The only drawback to this classification system is its complexity; however, the problem of acetabular and femoral bone loss is of sufficient complexity and variety that a simple classification system, although ideal, cannot be comprehensive. Regardless of the absence of a common language and a comprehensive classification system that is applicable to all types of reconstructions, it is clear that femoral bone loss is a problem that will continue to challenge orthopaedic surgeons. It is only by careful and methodical analysis of patients who have femoral bone loss and by meticulous attention being paid to detail in preoperative evaluation and investigation, surgical planning, and the recording of outcomes that we will be able to improve our treatment of this difficult problem.