Implant fixation, bone reconstruction, and ligament balancing are the three primary goals of revision total knee arthroplasty (Fig. 70-1). After failure occurs one or more times, fixation is difficult to achieve with cement because the cancellous bone has been depleted, so it is tempting to cement the implant to diaphyseal cortical bone. Use of cement leads to compromise of even more bone stock, and if removal is necessary as in cases of infection, diaphyseal osteotomy and extensive exposure almost certainly will be required. This complex set of circumstances may produce a situation that only can be salvaged by amputation in cases of repeat failure. A more reliable and durable surgical technique uses an uncemented stem to engage the isthmus and rim contact to engage the metaphyseal cortical bone. This technique creates a stable construct around which the bone can be rebuilt.¹,²,³ In almost all cases of revision, the implant can be fixed to available bone stock, which obviates massive allografts that do not reconstitute the lost bone stock and often fail due to late collapse and infection.⁴ Two major concerns with massive bone grafting—vascularization and incorporation—remain significant issues in the knee,⁴ and bone grafting with allograft still raises the questions of immune compatibility. Bone tissue itself is not highly immunogenic, whereas the marrow cells do incite a vigorous immune response⁵ and can create an inflammatory process that blocks ossification and incorporation of the graft.⁶

An effort has been made since 1984 to reconstruct clean or infected failed total knee arthroplasty with cementless techniques and to fix the implants directly to the patient’s remaining bone structure. Durability of the construct and reliability of fixation of the implants have been very good, and repeated revision due to mechanical failure has been rare.¹,²,³,⁷,⁸

In cases of infection around a total knee prosthesis, the standard treatment has been to remove the implants, treat with antibiotics for 6 weeks, and finally perform revision arthroplasty with antibiotic-loaded cement.⁹,¹⁰,¹¹,¹² Cementless reconstruction, however, is attractive for these revision cases because further bone destruction is avoided and bone stock also can be restored.¹,²,¹³,¹⁴ In the early series, the implants were removed and the knee was thoroughly debrided and then the patient was treated with parenteral antibiotics for 6 weeks. Three months after the final débridement, the joint was reconstructed using stemmed implants and morselized allograft. After obtaining nearly uniform success in eradicating the infection and achieving successful fixation with cementless reconstruction of the joint, an infusion technique was developed to deliver antibiotics in high concentration directly into the joint.¹⁵,¹⁶ With this innovation, a direct exchange single-stage revision was done and the 3-month waiting period was eliminated. In these cases, no bone graft was used, and the implants were fixed firmly to diaphyseal cortical bone with either a fluted or fully porous-coated stem and the metaphyseal rim was seated directly on the remaining cortical shell.¹⁶,¹⁷,¹⁸ Despite the absence of grafting of substantial defects in the metaphyseal bone, fixation was uniformly successful in these early series, and eradication of the infection was achieved in more than 95% of cases infected with resistant organisms.¹⁶,¹⁷,¹⁸