Cementless stem fixation in revision TKR also has many benefits (Fig. 47.2). A well-centered long press-fit stem facilitates component alignment by strictly directing the articular component [8]. Consequently, a revision system that does not allow for correction of the articular component position with offset stems will often produce cortical overhang or undersizing of articular components. In clinical practice most surgeons apply a hybrid fixation technique cementing the articular components and use a non-cemented, long press-fit stem [12, 13]. The long stems confer excellent stability to the implant and are easily removed if necessary [14]. Porous-coated stems also achieve excellent fixation but their removal is very challenging and as a result their use is limited in clinical practice [15].

A good, full fit in the canal of the diaphysis has been suggested for long-term survival of uncemented stems [12]. The intramedullary canal should be reamed until adequate cortical contact is made to allow for press-fit fixation of the cementless stem [13]. However, there is no clinical data available to verify this.

“End of the stem pain” has been described to be a more prevalent and severe problem with uncemented stem fixation, than with cemented stems [16]. The press-fit insertion of a cementless stem may increase the risk of penetration of the cortical bone during reaming and in the event of fractures during the insertion of trials or implants.

For uncemented stems there is only short to [17, 18] midterm data available [6, 13–15, 19–21]. In these studies the failure rate of press-fit stems was reported to be between 2 and 16 %.

In revision TKR the femoral condylar bone is often of poor quality. Bone may be osteopenic, poorly vascularized, and significantly reduced in stock due to prior surgery, infection, or osteolysis. With insufficient condylar bone stock, rigid fixation in the metaphyseal-diaphyseal junction must be obtained. To augment fixation in revision TKR, femoral and tibial metaphyseal sleeves have recently been introduced. Highly porous tantalum metaphyseal-filling cones were designed to accommodate metaphyseal bone loss [22–25]. Early clinical results with these devices are promising [26]. At short-term follow-up, structural support for the implants of a revision TKR were possible in some series [27]. Metal sleeves, which are usually used without cement, were introduced for this purpose [28]. The metaphyseal-diaphyseal junction is prepared with a broach to allow the sleeves to achieve initial axial, rotational, and coronal stability which permits immediate weight-bearing [28].

A short-term study was conducted in our institution using these sleeves without cement. Twenty patients were followed, who underwent revision TKR with non-cemented, porous-coated proximal tibial sleeves (Figs. 47.3 and 47.4). The use of tibial sleeves was deemed appropriate based on bone stock, age, and activity level. To measure performance, postoperative ranges of motion (ROM), Knee Society Scores (KSS), and Knee Society Functional Scores (KSFS) were taken at a minimum of 6 months follow-up. Radiographs were also evaluated for component positioning, subsidence, or loosening. Survivorship at a mean of 1.2 years follow-up (0.5–1.8 years) was 100 % without subsidence, change in component positioning, loosening, or radiographic demarcation. Despite the short follow-up period, patients who underwent revision TKR with the porous-coated proximal tibial sleeves demonstrated excellent efficacy and recovery, in terms of both pain and function. Osseointegration begins to become apparent about 6 months postoperatively. These results may justify increased use of non-cemented proximal tibial sleeves. However, long-term follow-up is necessary to show if bone adheres to and integrates fully into the prosthesis.