Custom made acetabular prosthesis are a valid option for the reconstruction after the resection of pelvic tumors. They should guarantee a stable and reliable reconstruction for the expected survival of the patient. Nevertheless in many cases periacetabular metastatic lesions have been compared to high grade (IIIA-B) Paprosky defects, but treated with low or intermediate longevity implants. Some complex post-traumatic scenarios or total hip arthroplasty (THA) multiple failures need a reconstruction according to oncologic criteria to fill in the huge defect and to obtain an acceptable function. The aim of the study is to compare 3D custom-made implants for tumors and for THA failures. Three custom-made implants after tumor resection (group A: 1 chondroblastic osteosarcoma, 1 bifasic synovialsarcoma, 1 high grade chondrosarcoma) were evaluated and compared to 3 acetabular complex reconstructions after non-oncologic bone defect (group B: 3 cases of aseptic loosening after at least 2 revisions). All the implants were case-based designed, 3D printed, and realized with porous or trabecular surfaces on a Titanium base prosthesis. Age range 16–70 ys in oncologic patients and 60–75 ys in non-oncologic patients. The bone defect to be reconstructed after tumor resection was classified according to Enneking zones (1 type 1-2-3 resection, 1 type 2 resection, 1 partial type 2 resection). Non-oncologic cases were comparable in term of remaining bone stock and classified according to Paprosky classification for acetabular defects as 1 type IIIA an 2 type IIIB. Complications, MSTS functional score, necessity of walking-aids were evaluated at minimum follow up of 1 year.Introduction and Purposes
Materials and Methods
The reconstruction of the knee in growing children considers many options and the chosen solution is often patient (or surgeon) based. Megaprostheses represent a reliable solution but quite expensive in the non-invasive growing version and not free from complications. In an Italian reference center for Bone and Soft tissue sarcomas, following the experience of Rizzoli Institute in Bologna, we performed the reconstruction with a resurfaced allograft for the distal femur or the proximal tibia in selected patients. The aim of the study is to confirm the reliability of this technique and to identify its potential advantages and indications. Among 60 children below 16 years old with bone sarcomas (39 osteosarcomas, 21 Ewing's sarcomas, age range 4–16) treated since 2007, 35 cases were around the hip and the knee. 7 pediatric knees (age range 5–12 ys) with the tumor involving the epiphysis were reconstructed using a resurfaced allograft for distal femur (2) or proximal tibia (6) leaving intact the other half of the joint. Functional outcome (MSTS score), complication rate, and oncologic follow up were evaluated.Introduction
Methods
Giant cell tumor (GCT) of bone is an aggressive tumor with high rate of recurrence. Bad prognosis factors were inquired, without a definite identification: type of treatment, soft tissue invasion, high proliferation rate at histology, pathologic fracture. From January 2000 to February 2008, 38 patients affected by GCT were treated in a regional reference centre, 17 male, mean age 32 (range 16–69, median 29); one patient had 2 localizations (tarsal bone and proximal tibia); 3 were recurrences previously treated in other hospitals. Seven cases were in upper limb, 1 case in the sacrum, 30 in lower limb (20 around the knee); fracture at presentation was present in 6 cases; bone aneurismal cyst (ABC) was associated in 4 cases. Five cases in stage 3 were treated by bone resection followed in 4 cases by allograft and/or prosthesis (no reconstruction in 1 proximal fibula excision); 33 cases were treated by curettage, local chemical (phenole) and mechanical adjuvants (burring), filling with bone grafts in 13 cases, cement in 8 cases, cement and allografts in subchondral area in 11 cases. The sacral lesion was only curetted. Seven patients developed a local recurrence, in 2 patients twice, for a total of 9 recurrences (19% of treatments). Recurrences occurred in 2 proximal tibia, in 2 distal femurs, in 1 proximal femur, in 1 distal radius and in 1 proximal fibula. The first treatment was bone grafts in 3 cases (23% of recurrence), bone cement and grafts in 2 cases (18% of recurrence), cement in 1 case (12% of recurrence), resection in the proximal fibula with severe soft tissue invasion. Two patients with associated ABC developed a recurrence and two with fracture at presentation. In this study, increased rate of recurrences occurred with pathologic fracture at presentation, soft tissue invasion and ABC association.
PET/CT is successfully used in metabolic characterization of lung nodules in adult patients. An SUV max of 2.5 is generally accepted to distinguish benign from malignant lesions; for small solitary lung nodules some authors recommend visual evaluation rather than only SUV, suggesting that classical SUV criterion of 2.5 is inappropriate. In pediatric patients interpretation of nodular opacity is still a clinical problem: specificity of CT in a pulmonary nodule, especially when small, is still limited. Aim of this prospective study was to evaluate PET/ CT for non invasive characterization of pulmonary nodules in pediatric bone sarcomas.
Prospective studies are needed to clarify benefit of PET/CT in management of these patients.
