The use of a navigation system in musculoskeletal tumour surgery enables the integration of pre-operative CT and MRI images to generate a precise three-dimensional anatomical model of the site and the extent of the tumour.

We carried out six consecutive resections of musculoskeletal tumour in five patients using an existing commercial computer navigation system. There were three women and two men with a mean age of 41 years (24 to 47). Reconstruction was performed using a tumour prosthesis in three lesions and a vascularised fibular graft in one. No reconstruction was needed in two cases. The mean follow-up was 6.9 months (3.5 to 10). The mean duration of surgery was 28 minutes (13 to 50). Examination of the resected specimens showed clear margins in all the tumour lesions and a resection that was exactly as planned.

Curettage and packing with polymethylmethacrylate cement is a routine treatment for giant-cell tumour (GCT) of bone. We performed an in vitro evaluation of the cytotoxic effect of a combination of cement and methotrexate, doxorubicin and cisplatin on primary cell cultures of stromal GCT cells obtained from five patients. Cement cylinders containing four different concentrations of each drug were prepared, and the effect of the eluted drugs was examined at three different time intervals.

We found that the cytotoxic effect of eluted drugs depended on their concentration and the time interval, with even the lowest dose of each drug demonstrating an acceptable rate of cytotoxicity. Even in low doses, cytotoxic drugs mixed with polymethylmethacrylate cement could therefore be considered as effective local adjuvant treatment for GCTs.

We treated 50 patients with bony malignancy by en-bloc resection, extracorporeal irradiation with 50 Gy and re-implantation of the bone segment.

The mean survivor follow-up was 38 months (12 to 92) when 42 patients were alive and without disease. There were four recurrences. The functional results were good according to the Mankin score (17 excellent, 13 good, nine fair, three failures), the Musculoskeletal Tumour Society score (mean 77) and the Toronto Extremity Salvage score (mean 81). There was solid union, but bone resorption was seen in some cases. The dose of radiation was lethal to all cells and produced a dead autograft of perfect fit.

Extracorporeal irradiation is a useful technique for limb salvage when there is reasonable residual bone stock. It allows effective re-attachment of tendons and produces a lasting biological reconstruction. There should be no risk of local recurrence or of radiotherapy-induced malignancy in the replanted bone.