Some patients present for total hip replacement with a femoral deformities or retained implants that will require ancillary procedures to remove or necessitate an osteotomy before performing a the hip replacement. Sometimes a very short femoral prosthesis can be used but sometimes even this will not fit. Removal of the blocking implant has been associated with additional operative time, blood loss, and cost. Intramedullary nails can be difficult to remove due to incarceration. Also, such procedures can result in longer and more restricted recovery and/or complications.
Performing a canal-sparing hip resurfacing is an attractive option. Possibly the only uniform agreement about hip resurfacing is that it requires less access to the femoral can. For some surgeons the only indication for hip resurfacing is a blocked femur and some, even then, do not recommend the procedure. Hip resurfacing has the possible benefits of a less complex procedure, improved functional outcomes, better patient survivorship, and a less complicated revision should failure occur. Improved techniques, improved instrumentation, and highly cross linked polyethylene have resulted in much better outcomes and survivorship and avoids the issues related to metal-on-metal resurfacing procedures. The outcomes of hip resurfacing with a blocked femoral canal have been excellent in the 356 patients we have treated. Also the 12-26% complication rates associated with removing blocking implants to perform a total hip replacement is avoided. Canal sparing hip replacement is a successful, less complicated and preferred option over conversion total hip replacement when there is deformity or a retained implant blocking the femoral canal.