Bone reconstruction in pediatric oncology always has to face two major problems: the frequent unavailability of small prosthetic tools and the difficulty in finding bone allografts of adequate size. Aim of this work is to present the research lines in this field, currently active in our institution to improve the planning and the results of reconstructive tumor surgery in children. Starting from patient’s CT data sets, subject-specific 3D models of bone segments can be created and compared with the similar models obtained by the CT analysis of massive allografts stored in the Rizzoli Bone Bank. In the same time the computer modelling technologies allow the development of three-dimensional environment, where the surgeon can navigate and exploit both artificial (prostheses, metallic plates and screws) or biological tools (bone allografts or autografts). The presented method has been utilized with success in 10 children (mean age 8, range 4–13) that underwent a skeletal reconstruction of the limbs in the last year (proximal humerus 1, diaphyseal humerus 1, total humerus 1, distal radius 1, proximal femur 3, diaphyseal femur 1, proximal tibia 1, diaphyseal tibia
The relationship with adamantinoma remains unclear, follow-up is suggested.
Infection occurred in 7 patients (10%) from 1 to 144 months (median 12 mo): in 6 patients prosthesis removal was needed to achieve healing. Mechanical complications were present in 19 patients (27%): 15 (21%) had prosthetic head instability (5 surgically treated), 2 breakage of the prosthetic stem and 2 prosthetic disassembly.
We have studied 560 patients with osteosarcoma of a limb, who had been treated by neoadjuvant chemotherapy, in order to analyse the incidence of local and systemic recurrence according to the type of surgery undertaken. Of these, 465 patients had a limb-salvage procedure and 95 amputation or rotationplasty. At a median follow-up of 10.5 years there had been 225 recurrences. The five-year disease-free survival and overall survival rates were 60.7% and 68.5%, respectively, with no significant difference between patients undergoing amputation and those undergoing resection. The incidence of local recurrence was the same for patients treated by either amputation or limb salvage and correlated significantly with the margins of surgical excision and the histological response to chemotherapy. The outcome for patients with a local recurrence was significantly worse than for those who had recurrent disease with metastases only. We conclude that limb-salvage procedures are relatively safe in osteosarcoma treated by neoadjuvant chemotherapy. They should, however, only be performed in institutions where the margins of surgical excision and the histological response to chemotherapy can be accurately assessed. If the margins are inadequate and the histological response to chemotherapy is poor an immediate amputation should be considered.
We describe 25 patients who were treated for a tumour of the proximal femur by resection and replacement with an uncemented, bipolar, modular prosthesis. When followed up after more than ten years four prostheses (16%) had required revision. Two joints showed wear and another necrosis of the acetabulum. One patient with loosening of the stem had been treated by radiotherapy to the femur. Articular cartilage seemed to be a reliable barrier to acetabular wear. Very few signs of the formation of particulate debris were observed. The most obvious feature in the bone-stem relationship was stress shielding, seen as osteoporosis of the proximal part of the femur around the stem in 68%. Functional activity was satisfactory in 68% of the patients. A better system of reattachment of the soft tissues is needed to avoid pain and a persistent limp.