Metaphyseal Fixation in Revision Total Knee Arthroplasty: Indications and Techniques
Orlando Medical Center, Orlando, FL, USA.The Journal of the American Academy of Orthopaedic Surgeons (Impact Factor: 2.53). 06/2011; 19(6):311-8.
The need for revision total knee arthroplasty (TKA) is on the rise. Challenges to attaining durable, stable, well-functioning revision TKA include bony deficiency, periarticular osteopenia, deformity, and soft-tissue imbalance. Defect management often requires the use of stems, cement, metal augmentation, or allograft. Recently, there has been interest in obtaining fixation in the metaphyseal region in an attempt to improve construct stability while managing bony deficiency. Often, the metaphyseal bone is well vascularized, which provides an opportunity for additional fixation with cement, allograft, trabecular metal cones, or stepped porous-coated sleeves. Multiple series have documented good survivorship at short-term follow-up with trabecular metal cones and porous-coated sleeves. These newer technologies offer biologic fixation and are useful for treating bony defects that are not easily managed with other methods. Long-term studies are needed to determine the durability of these constructs. Concerns persist regarding stress shielding and difficulty of removal. Familiarity with the rationale and strategies for metaphyseal fixation in revision TKA is a valuable addition to the armamentarium of the revision surgeon.
Article: Revisionsimplantate der Zukunft[Show abstract] [Hide abstract]
ABSTRACT: Die stetig wachsende Zahl an primär implantierten Hüft- und Knieprothesen weltweit bedingt eine ebenso steigende Anzahl von Revisionsoperationen. Da zum einen die Lebenserwartung steigt und die Patienten oftmals multiple Wechseloperationen erhalten, müssen im Rahmen der Revisionen mitunter hochgradige Knochendefekte therapiert werden. In den letzten Jahren konnten durch diverse Neuerungen in der Endoprothetik die operativen Möglichkeiten erweitert werden. Hochporöse Metalle erlauben als Oberflächenbeschichtung oder Augmente eine bessere Verklemmbarkeit und Primärstabilität der Hüft- und Knieprothesen. Modulare Prothesensysteme können an die Defektsituation des Patienten individuell angepasst werden. Neue Beschichtungen der Komponenten steigern die Osteointegrationsfähigkeit, stellen neue Alternativen bei Allergien dar oder eröffnen in Zukunft womöglich neue Therapieansätze bei septischen Revisionen. Die derzeit auf dem Markt erhältlichen Neuerungen brachten in den ersten kurz- bis mittelfristigen Nachuntersuchungen gute Ergebnisse.
- [Show abstract] [Hide abstract]
ABSTRACT: Background Tantalum-made cones have been developed to compensate for large bone defect involving metaphyseal segment or major portion of the condyle or plateau during knee revision prosthetic surgery. Materials and methods We present our experience with femoral and tibial tantalum cones in 11 knees (12 cones overall were used, 6 on femur and 6 on tibia) with 2B or 3 Engh defect type during knee revision arthroplasty. Both cemented and cementless cones were used. Patients were submitted to a specific study protocol in order to exclude a new or persistent infection. Only one intra-operative complication not related to the implantation of the trabecular metal cone was observed. Results Neither early nor late post-operative re-infection was reported in our series at a mean follow-up of 39.8 months. Radiological analysis showed no cases of aseptic loosening or migration of the components. The only post-operative complication was delayed union of the tibial tuberosity in a patient who required osteotomy for surgical exposure. All patients improved both clinically and functionally. Conclusions The results of this study support the use of femoral and tibial porous tantalum metaphyseal cones as a viable option for revision knee arthroplasty with large amount of bone defects in both tibia and femur. We think that the main advantages of tantalum cones compared to structural bone graft lie in faster full weight-bearing recovery and in the cones' potential long-term maintenance of mechanical support. By our results, we can eventually exclude any concern regarding a possible direct correlation of the trabecular metal cones with re-infection.
- [Show abstract] [Hide abstract]
ABSTRACT: According to current prognostic studies the numbers of revision operations of hip and knee arthroplasty will increase worldwide. As many patients undergo several revisions and become older at the same time, orthopedic surgeons will have to cope with vast bony defects during operations. The introduction of highly porous metals as surface layer or metal augments has facilitated primary stabilization of prostheses. Short and mid-term results of these new products are promising. New developments in coatings, such as cationic antimicrobial peptides represent new alternatives for antibacterial therapy of periprosthetic infections and increase osteointegration of prosthesis components. Furthermore, the new revision systems have a modular design and can be individually adapted to the patient's bony conditions during operations. In most cases this can be done without cement or in a hybrid technique.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.