We reviewed 124 patients with a conventional pelvic chondrosarcoma who had been treated over a period of 20 years. We recorded the type of tumour (central or peripheral), type of operation (limb salvage surgery or hemipelvectomy), the grade of tumour, local recurrence and/or metastases, in order to identify the factors which might influence survival. More satisfactory surgical margins were achieved for central tumours or in those patients treated by hemipelvectomy. However, grade 1 tumours, whatever the course, did not develope metastases or cause death, while grade 3 tumours had the worst outcome and prognosis. Central, high-grade tumours require aggressive surgical treatment in order to achieve adequate surgical margins, particularly in those lesions located close to the sacroiliac joint. By contrast, grade 1 peripheral chondrosarcomas may be treated with contaminated margins in order to reduce operative morbidity, but without reducing survival.

Bone metastases are a very common problem in prostate cancer. They are associated with considerable morbidity, adversely affect quality of life and frequently lead to advanced bone events (so-called skeletal-related events, SREs); SREs include fractures, spinal cord compression and the requirement for bone surgery or bone radiation. The aim of this paper was to evaluate currently available treatment options in the prevention and management of SREs and bone metastases in men with castration-resistant prostate cancer and to outline the importance of interdisciplinary management strategies. It also discusses the diagnostic workup of osseous metastases and practical considerations for the utilization of bone-targeted therapies in accordance with current guidelines to provide a consensus for special and/or difficult clinical situations.

Background: Osteosarcoma and Ewing sarcoma are more common diagnoses in preadolescent and adolescent children compared with the adult population. A greater percentage of patients are treated with limb salvage and reconstruction using modular tumor endoprostheses. Implant-to-bone fixation can be cemented or cementless. Cementless tumor endoprostheses rely on biologic osteointegration for implant stability, and chemotherapy during childhood and adolescence can disturb the bone turnover rate and reduce bone mineral density, which in turn may predispose patients with uncemented endoprostheses to a high rate of revision surgeries. Questions/purposes: (1) What is the cumulative incidence of revision operations for any cause (wound dehiscence, periprosthetic fracture, hinge breakage, aseptic loosening, infection, local recurrence, implant removal, and amputation) of cementless tumor endoprostheses around the knee? (2) What is the cumulative incidence of aseptic loosening, periprosthetic fracture, hinge breakage, and infection, and what proportion of patients had other complications? (3) What was the mean limb length discrepancy (LLD) at the time of skeletal maturity? (4) What was the median Musculoskeletal Tumor Society (MSTS) score at most recent follow-up or just before implant removal/amputation if implant removal/amputation were performed? Methods: Between 2008 and 2019, we treated 328 patients younger than 18 years for a primary bone sarcoma around the knee at our institution. Of those, 138 were treated with resection and reconstruction using two different types of modular tumor endoprostheses. During this period, our general indications for an endoprosthesis were patients who were candidates for an intraarticular resection of the distal femur or proximal tibia and who were at least 10 years of age. Uncemented fixation was always preferred. Cemented fixation was only done when intraoperative press-fitting of a cementless stem was not possible. Among uncemented implants, 26 patients died before completing 2 years of follow-up with intact implants and without further surgery, three were lost to follow-up before 2 years, and four patients received implants as a secondary salvage surgery after a failed primary biologic reconstruction with a vascularized fibular bone graft, leaving 94 patients for evaluation in this retrospective study. The mean age was 15 ± 2 years and the median (interquartile range) follow-up duration was 51 months (39 to 74). We did a competing risks analysis to tally cumulative incidence of all-cause revision procedures and cumulative incidence of aseptic loosening, periprosthetic fracture, hinge breakage, and infection. Other complications, including wound dehiscence, local recurrence, and stem breakage, were characterized descriptively and ascertained by review of electronic records of a longitudinally maintained institutional database by the treating surgeons. LLD was measured by serial clinical assessments and CT scans, starting since primary salvage surgery and until the latest follow-up of every patient. For the analysis of remaining LLD, we included only patients who were skeletally immature at time of primary resection and who had reached skeletal maturity by their latest follow-up (73% [69 of 94]). Functional outcome was assessed using MSTS scores obtained from a review of electronic records of a longitudinally maintained institutional database. Results: The 8-year cumulative incidence of revision surgery for any cause was 32% (95% confidence interval 23% to 42%). The 8-year cumulative incidence of aseptic loosening was 5% (95% CI 2% to 11%), periprosthetic fracture was 9% (95% CI 4% to 15%), hinge breakage was 19% (95% CI 12% to 28%), and infection was 7% (95% CI 3% to 14%). Other complications included wound dehiscence in 2% (2 of 94), stem breakage in 2% (2 of 94), and local recurrence in 2% (2 of 94) of patients. Stress shielding of the cortical bone around implanted stems was observed in 26% (24 of 94). The mean LLD for those who were skeletally immature at the time of primary resection and who reached skeletal maturity was 3.5 ± 2.6 cm. At latest follow-up, the median (IQR) MSTS score for all patients, excluding those who had complete implant removal or amputation, was 26 (24 to 27) of a maximum score of 30. Conclusion: We observed a high rate of early revision and relatively frequent complications associated with the use of cementless fixation, and although this was not a comparative study, the findings were not superior to those reported by others who have studied cemented fixation for this indication. Furthermore, there may be some disadvantages with cementless fixation, such as stress shielding. Comparative studies about fixation methods are needed. The prevalence of bushing breakage in the current study highlights the importance of future modifications in the hinge design of both types of prostheses used in this study. Patients who were skeletally immature at the time of primary surgery had a LLD no more than 5 cm at skeletal maturity; consequently, nonexpandable endoprostheses may be appropriate for some adolescent patients who have limited remaining growth, although which patients are best suited for this approach would require specific study. Level of Evidence: Level IV, therapeutic study.

Introduction: Skeletal involvement in children with Langerhans cell histiocytosis (LCH) is a common feature of the disease. Several options for the treatment of these skeletal lesions have been reported. We describe our experience in the treatment of skeletal involvement of LCH in this retrospective case series study, entailing anatomic distribution, pattern of healing, skeletal deformities, and functional outcome of skeletal LCH. Methods: A retrospective analysis was conducted for patients diagnosed with LCH and having skeletal lesions in the period between 2007 and 2015. Out of a total of 229 cases, 191 (83.4%) had skeletal involvement. Bone healing was divided into partial and complete based on the size of lesion and cortical changes in plain radiograph. Skeletal deformities were serially measured. Time to pain control, resumption of weight bearing, and the final functional status of the patient were reviewed. Results: The mean age at presentation was 4.4 years (3 m–14.8 y) and the mean follow-up period was 53.3 months (0.2–120.7). After screening of skeletal and extra-skeletal lesions, 59 patients (31%) had M-S (Multisystem) LCH and 132 (69%) had S-S (Single system) LCH. Unifocal bone lesions were found in 81 (42.5%) patients, and multifocal bone lesions in 110 patients (57.5%). Single or multiple bone lesions were found in the craniofacial bones in 152 patients (79.5%), femur in 19 patients, (10%), ribs in 18 patients (9.4%), spine in 15 patients (8.1%), pelvis in 14 patients (7.3%), scapula in 8 patients (4.1%), humerus in 6 (3.1%), clavicle in 6 patients (3.1%), tibia in 3 patients (1.5%), radius in 3 patients (1.5%), and the ulna in 2 patients (1%) patients. No lesions were found in the fibula, hand, or foot. Out of all skeletal lesions, 179 (93.7%) patients were treated either medically or conservatively and 12 patients (6.2%) were treated surgically. The mean time to complete healing was 5.2 months (2–12). Skeletal complications included: pathologic fractures (9 vertebra plana, 5 long bone, 1 iliac bone), deformities (9 thoracolumbar kyphosis, 2 cervical spine subluxations, 2 coxa vara deformity of the proximal femur and one flattening of iliac bone). Conclusion: Non-operative treatment can lead to adequate bone healing in few months period. Partial or complete remodeling of bone deformities can be observed without surgical correction. However, surgical intervention might be indicated when cervical spine affection may lead to instability and subsequent neurological affection. Functional impairment is rarely caused by skeletal lesions in LCH.

Background Most reports on skeletal reconstruction using vascularized fibular free flap include patients with varying age groups and anatomic locations. This study has limited the inclusion criteria to pediatric and adolescent patients diagnosed with bone sarcoma of the femoral shaft. Methods Forty-one patients, diagnosed with a malignant bone tumor of the femoral shaft (21 Ewing's sarcomas and 20 osteosarcomas), were locally treated by joint sparing wide resection and reconstruction using a vascularized fibular free flap. All clinical and radiographic data were reviewed for graft healing and hypertrophy as well as oncologic and functional outcome. Results The mean follow-up period was 48.7 months (12–104 months). The mean age at presentation was 10.3 years (5–17 years). The average length of the resected femoral shaft was 19.2 cm (15–24 cm) and the average length of the harvested fibula was 17.4 cm (15–21 cm). The mean time to union was 4.8 months (1–6 months) and the mean hypertrophy index was 78% (15.5–184%). Complications included 12 fractures (33.3%), 5 non-unions (13.8%), and 5 failures of graft hypertrophy (13.8%). At the latest clinical evaluation, the mean MSTS score was 81% (56–100%) and the mean limb length inequality was 4.75 cm (3–11 cm). Conclusion Despite the high functional demand and deleterious effect of chemotherapy on bone healing, reconstruction of the femur by vascularized fibular free flap in pediatric bone sarcomas can lead to a good functional outcome. Complications, such as fracture and non-union, can be successfully treated by revision of fixation and autologous iliac crest grafting. Level of Evidence IV.