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.

Aims: Crosslinked acetabular inserts have been introduced as a solution to the wear related periacetabular osteolysis, caused by the polyethylene wear debris. Laboratory tests and simulators have demonstrated that crosslinked-polyethylene has a higher resistance to wear than conventional polyethylene. However, studies have shown early crack or degeneration of crosslinked inserts. Concerns still remain about the clinical performances of crosslinked inserts. Although questionable, the roentgenographic measurement of the wear of the cup represents an indicator of the performance of the implant. Early catastrophic failures of other inserts taught us that for new materials it is mandatory to conduct an accurate clinical surveillance. In this work the radiographic-evaluated linear wear of a group of cross-linked inserts is compared to that of a non-crosslinked inserts for the same socket at 5 years.

Methods: From 2000 to 2002 we implanted a series of cups in which crosslinked and conventional acetabular inserts were placed randomly. Patients from each group underwent radiographic assessment after implantation, at 3 and 6 months and then yearly. Radiographs were obtained using a digitalized image system, which allowed a computerized bi-dimensional measurement by a specially developed Auto-CAD program. 12 healthy and active patients (6 crosslinke – 6 conevtional UHMWPE) have been selected for measurement.

Results: No macroscopic signs of loosening, mobilization and osteolysis were detected. Despite an increased wear rate for the conventional insert, no statistically sig-nificant differences of the linear wear were detected at five years for the two groups.

Conclusions: Longer follow-up and larger case studies are needed for more definitive conclusions. Nevertheless, this preliminary study shows that crosslinked polyethylene in vivo at 5 years does not give early failures and that its linear wear in the short term does not differ from that of a conventional polyethylene. Several other factors, such as the number and dimension of the debris, which are not detected by roentgenographic measurements, might be taken into consideration. Moreover it has been hypothesized for the crosslinked polyethylene an early plastic deformation, with consequent penetration of the head without wearing, which could affect the measurement on plan radiographs. Despite these limitations, roentgenographic measurements are quick and easy to perform, and therefore might be useful for the clinical practice of the periodical evaluation of the implants.