Paediatric bone sarcomas around the knee are often amenable to either endoprosthetic reconstruction or rotationplasty. Cosmesis and durability dramatically distinguish these two options, although patient-reported functional satisfaction has been similar among survivors. However, the impact on oncological and surgical outcomes for these approaches has not been directly compared. We retrospectively reviewed all wide resections for bone sarcoma of the distal femur or proximal tibia that were reconstructed either with an endoprosthesis or by rotationplasty at our institution between June 2004 and December 2014 with a minimum two year follow-up. Pertinent demographic information, surgical and oncological outcomes were reviewed. Survival analysis was performed using the Kaplan-Meier method with statistical significance set at p<0.05. Thirty eight patients with primary sarcomas around the knee underwent wide resection and either endoprosthetic reconstruction (n=19) or rotationplasty (n=19). Groups were comparable in terms of demographic parameters and systemic tumour burden at presentation. We found that selection of endoprosthetic reconstruction versus rotationplasty did not impact overall survival for the entire patient cohort but was significant in subgroup analysis. Two-year overall survival was 86.7% and 85.6% in the endoprosthesis and rotationplasty groups, respectively (p=0.33). When only patients with greater than 90% chemotherapy-induced necrosis were considered, overall survival was significantly better in the rotationplasty versus endoprosthesis groups (100% vs. 72.9% at two years, p=0.013). Similarly, while event-free survival was not affected by reconstruction method (60.2% vs. 73.3% at two years for endoprosthesis vs rotationplasty, p=0.27), there was a trend towards lower local recurrence in rotationplasty patients (p=0.07). When surgical outcomes were considered, a higher complication rate was seen in patients that received an endoprosthesis compared to those who underwent rotationplasty. Including all reasons for re-operation, 78.9% (n=15) of the endoprosthesis patients required a minimum of one additional surgery compared with only 26.3% (n=5) among rotationplasty patients (p=0.003). The most common reasons for re-operation in endoprosthesis patients were wound breakdown/infection (n=6), limb length discrepancy (n=6) and periprosthetic fracture (n=2). Excluding limb length equalisation procedures, the average time to re-operation in this patient population was 5.6 months (range 1 week to 23 months). Similarly, the most common reason for a secondary procedure in rotationplasty patients was wound breakdown/infection, although only two patients experienced this complication. Average time to re-operation in this group was 23.8 months (range 5 to 49 months). Endoprosthetic reconstruction and rotationplasty are both viable limb-salvage options following wide resection of high-grade bony sarcomas located around the knee in the paediatric population. Endoprosthetic reconstruction is associated with a higher complication rate and may negatively impact local recurrence. Study of a larger number of patients is needed to determine whether the reconstructive choice affects survival

Purpose. Rotationplasty was first described in 1930 by Borggreve for treatment of limb shortening with knee ankylosis after tuberculosis. In 1948, Van Nes described its use for management of congenital defects of the femur and in the 1980s, Kotz and Salzer reported on patients with malignant bone tumors around the knee treated by rotationplasty as an alternative to above-knee amputation. Currently, rotationplasty is one of the options for surgical management of lower extremity bone sarcomas in skeletally immature patients but alternative limb salvage techniques, such as the use of expandable endoprosthesis, are also available. Despite rather satisfactory functional results have been uniformly associated with rotationplasty, concern still exists about the potential psychological impact of the new body imagerelated to the strange appearance of the rotated limb. Results of rotationplasty for sarcomas of the distal femur over a 20-year period were analyzed, focusing on long-term survival, function, quality of life and mental health. Method. Retrospective study of 73 children who had a rotationplasty performed at two institutions between 1984 and 2007 for a bone sarcoma of the distal femur; 42 males and 31 females, mean age at surgery 8.7 yrs (range 3–17). Four patients were converted to transfemoral amputation due to early vascular complication; 25 eventually died of their disease (mean survival 34 months, range 4–127). The 46 remaining survivors were evaluated for updated clinical outcome, MSTS score, gait analysis, SF-36 score, quality of life interview and psychological assessment at mean follow-up of 15 yrs (range 3–23). Results. Overall survival was 64%. All the survivors were disease-free at last follow-up. Four patients required hardware revision for nonunion and subsequently healed. Three patients refused participation in the long-term follow-up study. Mean MSTS score was 79 (range 64–88). SF-36 score was obtained in 35 patients (age > 16); male patients showed a trend toward greater activity and vitality. Compared to age-group norms, rotationplasty scores were lower for physical activity level (p <0.05) and higher for general health perception (p = 0.05) and mental health (p < 0.05). Conclusion. Rotationplasty remains a durable reconstructive option with good long-term function and acceptable psychological impact for children with bone sarcomas of the distal femur

Introduction. Historically, amputation or rotationplasty were the treatment of choice in skeletally immature patients. The introduction of expandable endoprostheses in the late 1980s offered the advantages of limb-salvage and limb length equality at skeletal maturity and a promising alternative with improved cosmetic results and immediate weight bearing. Objective. to describe the Rizzoli experience in reconstruction with three different types of expandable prostheses in growing children with malignant bone tumors of the femur, assess the outcome of limb salvage in these patients, analyze survival and complications related to these prostheses used over time. Materials and Methods. Between 1996 and 2010, 39 expandable implants were used in 32 children (16 boys and 16 girls; mean age, 9 years at initial surgery) with bone sarcomas of the femur treated with limb salvage using expandable prostheses. The most common diagnosis was osteoblastic osteosarcoma; all children were classified as having a stage IIB lesion and had preoperative and postoperative chemotherapy. The minimally invasive Kotz Growing prosthesis was used in 17 cases (10 primary implant and 7 revision after failure of non-invasive Repiphysis®), the non-invasive Repiphysis® in 15 cases and Stanmore® expandable prostheses in 7 cases. The mean follow-up was 48 months. Functional evaluation and survival analysis of the children and implants were performed. Results. The rate of implant-related complications was 51.3%; 9 prostheses (23%) were revised because of aseptic loosening, infection and breakage. The mean total lengthening was 26 mm (4 to 165 mm) achieved by 78 procedures (2.4 procedures/patient). Three of the nine children who reached skeletal maturity had limb length equality and six discrepancy of 15–30 mm. The survival of the children was 94% and 76% at 24 and 72 months. The survival of the primary prostheses was 90% and 70% at 24 and 72 months. Survival was significantly higher only for the Kotz compared to the Repiphysis® prostheses (p= 0.026). The mean MSTS score was excellent (79%) without a significant difference between the type of prostheses (p= 0.934). Conclusions. In the growing children expandable prostheses are viable reconstruction options with good and excellent oncological and functional outcome, and limb-length equality at skeletal maturity. Mechanical failures including aseptic loosening and breakage, dysfunction of the expansion mechanism, contractures especially around the knee, dislocation and infection were the most common; some designs have been associated with an unacceptably high inherent risk of complications. However, the non-invasive systems are associated with high complications and failure rates. Early experience is promising, but further study is warranted to determine long-term structural integrity of these newer designs