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There are several options for the treatment of patients with osteonecrosis about the knee. Three appear to be the most effective and include conservative treatment for small lesions without evidence of structural collapse, core decompression for relief of pain and possible delay in structural collapse in the patients with steroid-induced osteonecrosis, and either unicompartmental or total knee arthroplasty. Although other modalities have been reported, these three remain the most widely reported and generally offer the greatest success. With better recognition of these problems, longer duration follow-up, and larger patient series, the answers to the best treatment regimen will become better defined.

A review of our experience in total joint arthroplasty revealed that the cell saver was not cost-effective in the case of routine primary hip or knee replacement. Its use should be restricted to cases of revision hip and knee surgery in which infection has been ruled out. Preoperative aspiration remains the most reliable method for accomplishing this. However, if the aspiration is negative and the intra-articular fluid obtained at the time of surgery is suspicious for infection, either in appearance or on Gram stain or cell count, it is best to abandon use of the cell saver. Predonation should be routine for all hip replacement cases unless there are specific contraindications. In general, there is good acceptance of this program by patients, although a few have specifically indicated they would prefer to run the risk of homologous transfusion. Two units available for primary replacement are more than ample. In cases of revisions, a first revision justifies a minimum of 3 units. For complex revision cases involving patients with three or more previous procedures on the hip, or those requiring significant bone resection or large segment grafting, the maximum possible number of units should be obtained. Autologous blood reinfusion should be done for essentially the same indications as homologous transfusion even though risks are sharply reduced. The local source for autologous collection will then follow its own specific protocol for the disposition of remaining units. In every case, the surgical technique should be careful and directed toward limiting intraoperative blood loss.

In summary, reduction of blood loss and coincidental decrease in the number of blood transfusions is now of paramount importance in orthopaedic surgery. Methods to reduce blood loss include preoperative planning, hypotensive anesthesia, and meticulous surgical technique. If transfusion is necessary, autologous replacement is always preferable. Overall, the goals in blood conservation in surgery are first to decrease the amount of blood lost, and second to be sensible in replacement of this loss.

In summary, if the pathophysiology of surgical infection is understood and the principles of treatment are followed, dealing with the complex problems of infected transplants should be less formidable.