Page 75 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

Introduction
Surgical treatment of pelvic bone tumors continues to pose a challenge to the orthopaedic oncology community. Traditionally, pelvic tumors were resected
by means of hindquarter amputation, a procedure associated with detrimental
cosmetic, physical, and psychological outcomes1. At present, the majority of
patients can be treated with limb-salvaging internal hemipelvectomies1, 2. Complications nevertheless remain frequent, especially for resections comprising
the periacetabulum (Enneking type 2 or type 2–3)3-5, and for large tumors, which are
common in this location because pelvic tumors regularly attain large sizes before 4 diagnosis. Procedures in this location also can be complicated by inadequate
margins and, because the procedures are long, infection6, 7.
Apart from tumor resection, obtaining a well-functioning reconstruction is
challenging. As a result of the frequently massive extent of bone and soft tissue resection, the reconstructions are typically exposed to high biomechanical stresses. Reconstructive techniques remain a topic of debate; various biological, mechanical, and combined techniques have been advocated8-11. Disadvantages of biological reconstruction using allografts, include the high risk of infection, nonunion, and graft resorption12. Many authors therefore consider endoprosthetic replacement a better solution to achieve satisfactory and durable functional and cosmetic results6, 13, 14. Several new implants have been introduced during recent decades, including custom-made, saddle, and “inverted ice cream cone” or “pedestal cup” prostheses6, 9, 13, 15-17. Most of these have been associated with a disappointing frequency of mechanical complications and failures, especially in the long term, including (recurrent) dislocations (3% – 24%), aseptic loosening (3% – 15%), cranial migration, heterotopic ossi cation, and periprosthetic or prosthetic fractures9, 12, 13, 15, 17, 18. However, adequately comparing di erent techniques is di cult because most published results are derived from single-center case series with limited patient numbers.
In the leading center of the current study, a pedestal cup prosthesis (Zimmer, Freiburg, Germany) was used for periacetabular reconstruction between 2003 and 20089. We encountered frequent complications, but considered the basic concept behind the implant suitable because it allows for relatively easy, quick, and durable xation. Moreover, it allows for pelvic reconstruction even if only the medial ilium remains. We theorized that modi cation of the implant would aid to reduce complication rates and incorporated these ideas in the design of the LUMiC
LUMiC
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