Page 23 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

between host bone and the graft – presumably in combination with compression 1 at the junction – are the principal determinants of union114. However, the in uence
of contact at the allograft-host junction had never been evaluated properly. In
chapter 8, we present a study on the in uence of contact between the allograft
and host bone in intercalary reconstructions of the femur and tibia.
During the early 1990s, endoprosthetic implants rapidly re ned with respect to modularity and thus possibilities to reconstruct resected bone, consequently these implants popularised84, 112, 115-117. Endoprostheses have the advantage of providing a relatively easy and quick reconstructive technique which allows for early postoperative mobilisation and weight bearing22. Pioneering centers mainly used custom-made endoprosthetic devices during the 1970s and 1980s. An inherent but important disadvantage of custom-made implants is the lack of intraoperative exibility (i.e. modularity)118. MUTARS® (implantcast, Buxtehude, Germany) was one of the rst modular implant systems that were speci cally designed for reconstruction after tumor resection or extended revision arthroplasty. As opposed to custom-made implants, modular endoprostheses allow for intraoperative adjustment, for example when greater resection is needed than was anticipated118. Moreover, modular implants are available o -the-shelf and are generally less expensive than custom-made implants118, 119. Key features of the MUTARS® system include its uncemented, hexagonal-shaped stem, saw teeth at the junctions of stems and extension pieces to allow rotational adjustment, and the attachment tube for soft-tissue reconstruction120, 121. Encouraging results of its use in orthopaedic oncology and revision arthroplasty surgery were documented120, 122, 123. However, studies focusing on the long-term results of MUTARS® reconstructions around the knee were lacking, while studies on other endoprosthetic systems demonstrated that late complications are of frequent occurrence115, 116. In chapter 9, we present a study on distal femoral and proximal tibial replacements from two
Dutch tertiary referral centers121.
Finally, in chapters 10, 11, and 12, we present a general summary, general
discussion, and summary in Dutch.
General introduction
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