Outcomes of a Modular Intercalary Endoprosthesis as Treatment for Segmental Defects of the Femur, Tibia, and Humerus

Abstract

Background Resection of diaphyseal bone tumors for local tumor control and stabilization often results in an intercalary skeletal defect and presents a reconstructive challenge for orthopaedic surgeons. Although many options for reconstruction have been described, relatively few studies report on the functional outcomes and complications of patients treated with modular intercalary endoprostheses. Questions/purposes The objectives of this study were to examine clinical outcomes after reconstruction with a modular intercalary endoprosthesis with a specific focus on (1) the rate of complication or failure; (2) differences in complication rates by anatomic site; (3) functional results as assessed by the Musculoskeletal Tumor Society System (MSTS); and (4) differences in complication rate between patients treated with cemented versus noncemented fixation. Methods We conducted a retrospective chart review of patients treated with a modular intercalary endoprosthesis from three musculoskeletal oncology centers from 2008 to 2013. The indication for use of this intercalary endoprosthesis was segmental bone loss from aggressive or malignant tumor with sparing of the joint above and below and deemed unsuitable for biologic reconstruction. No other implant was used for this indication during this period. During this period, 41 patients received a total of 44 intercalary implants, which included 18 (40%) humeri, 5 (11%) tibiae, and 21 (48%) femora. There were 27 (66%) men and 14 (34%) women with a mean age of 63 years (range, 18-91 years). Eight patients (20%) had primary bone tumors and 33 (80%) had metastatic lesions. Thirtyfive (85%) patients were being operated on as an initial treatment and six (15%) for revision of a previous reconstruction. Twenty-nine (66%) procedures had cemented stem fixation and 15 (34%) were treated with noncemented fixation. The overall mean followup was 14 months (range, 1-51 months). Patients with primary tumors had a mean followup of 19 months (range, 4-48 months) and patients One or more of the authors (JB) has received funding from the Musculoskeletal Transplant Foundation and has also received fees from Merete Inc (Berlin, Germany) and Implant Cast (Buxtehude, Germany) outside of the submitted work and holds several patents and licensing fees with CreOsso LLC (Montclair, NJ, USA with metastatic disease had a mean followup of 11 months (range, 1-51 months). Causes of implant failure were categorized according to Henderson et al. [19] into five types as follows: Type I (soft tissue failure), Type II (aseptic loosening), Type III (structural failure), Type IV (infection), and Type V (tumor progression). At 2 years of followup, 38 (93%) of these patients were accounted for with three (7%) lost to followup. MSTS functional assessment was available for 39 of 41 patients (95%). Results At latest followup of these 41 patients, 14 (34%) patients were dead of disease, two patients (5%) dead of other causes, seven (17%) are continuously disease-free, one (2%) shows no evidence of disease, a...

Effects of Surgical Angiogenesis on Segmental Bone Reconstruction With Cryopreserved Massive‐Structural Allografts in a Porcine Tibia Model

“…Treatment of large segmental bone defects created by limb‐sparing tumor resection, infection, and traumatic loss has significant morbidity with all currently available methods, including vascularized autografts, prosthetic replacement, bone transport, and use of structural cryopreserved bone allografts (CBA) . Vascularized autologous bone provides superior rates of healing and remodeling than banked allogeneic bone .…”

Recombinant Human Bone Morphogenetic Protein 6 Delivered Within Autologous Blood Coagulum Restores Critical Size Segmental Defects of Ulna in Rabbits

“…( A ) Radiographs of all bone samples ( n = 5 per group) at week 23. ( B ) Radiographic grading scores (0–6) of all bone samples using an established scoring system . ( C ) 3D models (longitudinal and cross‐sectional) of bone healing in rabbits after ex vivo micro‐CT scan at week 23 after study termination.…”

“…BMP6 was chosen because it does not bind avidly to Noggin, (63) a natural BMP antagonist abundant in bone and induces downstream Radiographic grading scores (0-6) of all bone samples using an established scoring system. (38,39) (C) 3D models (longitudinal and cross-sectional) of bone healing in rabbits after ex vivo micro-CT scan at week 23 after study termination. Three bone samples per dose group are shown, with corresponding Xray image on the left.…”

“…Evaluation of rhBMP2 containing ceramic‐collagen composite device in posterolateral lumbar fusion (PLF), however, has not met primary endpoint and failed to get an FDA approval. This device was also reported to have unwanted side effects likely attributed to the use of a high dose of rhBMP2 and its weak binding to collagen‐ceramics …”

“…This device was also reported to have unwanted side effects likely attributed to the use of a high dose of rhBMP2 and its weak binding to collagen-ceramics. (6,(36)(37)(38) Here we describe an autologous bone graft substitute (ABGS) that is composed of recombinant human BMP6 (rhBMP6) combined with autologous blood coagulum (ABC) to guide the formation of new bone to promote bone healing in a large diaphysis segmental defect and bridge the gap. ABC circumvents the use of animal-derived collagen, limiting possible inflammatory processes due to its autologous nature, provides functional and physiological carrier for rhBMP6, and offers a flexibility to mold to the desired shape, thus facilitating its use within different anatomical structures.…”