Aims

The aim of this study was to assess orthopaedic oncologic patient morbidity resulting from COVID-19 related institutional delays and surgical shutdowns during the first wave of the pandemic in New York, USA.

Introduction. The use of computer navigation has a potential to allow precise tumour resection and accurate reconstruction of the resultant defect. This can be useful in difficult areas such as pelvis, diaphyseal (intercalary) resections and geometric bony resections. Methods. We have carried out resections of musculoskeletal tumours in 7 patients using an existing commercial computer navigation system (Orthomap 3D). CT & MRI scans of each patient were fused preoperatively using navigation software and the tumour margins were marked. The planes of tumour resection were defined on the 3D image generated. During surgery, trackers were attached to bone with tumour and registration performed. Instruments attached to navigation tracker were then used to identify the predetermined resection points. Of the 4 pelvic tumours, 1 had biological reconstruction with extra corporeal irradiation, 3 had endoprosthetic replacement & 1 did not need any bony reconstruction. 1 patient with proximal femur tumour needing extraarticular resection had endoprosthetic replacement. The 2 tibial diaphyseal tumours had biological reconstruction. Results. Examination of the resected specimens revealed tumour free margins. Postoperative radiographs showed resection and reconstruction as planned in all cases. In the patient with extraarticular proximal femur resection the hip joint was inadvertently exposed whilst making the acetabular osteotomy & in one patient with pelvic tumour the intra-operative registration could not be accurately performed as she was overweight and a real time matching of anatomy & virtual images was not achieved. Discussion and Conclusion. The use of computer navigation in musculoskeletal oncology allows integration of local anatomy and tumour extent and thus resection margins can be identified accurately. Our experience so far has been encouraging. Further clinical trials (multicentre) are required to evaluate its long term impact including functional & oncological outcomes

We report our experience of using a computer navigation system to aid resection of malignant musculoskeletal tumours of the pelvis and limbs and, where appropriate, their subsequent reconstruction. We also highlight circumstances in which navigation should be used with caution.

We resected a musculoskeletal tumour from 18 patients (15 male, three female, mean age of 30 years (13 to 75) using commercially available computer navigation software (Orthomap 3D) and assessed its impact on the accuracy of our surgery. Of nine pelvic tumours, three had a biological reconstruction with extracorporeal irradiation, four underwent endoprosthetic replacement (EPR) and two required no bony reconstruction. There were eight tumours of the bones of the limbs. Four diaphyseal tumours underwent biological reconstruction. Two patients with a sarcoma of the proximal femur and two with a sarcoma of the proximal humerus underwent extra-articular resection and, where appropriate, EPR. One soft-tissue sarcoma of the adductor compartment which involved the femur was resected and reconstructed using an EPR. Computer navigation was used to aid reconstruction in eight patients.

Histological examination of the resected specimens revealed tumour-free margins in all patients. Post-operative radiographs and CT showed that the resection and reconstruction had been carried out as planned in all patients where navigation was used. In two patients, computer navigation had to be abandoned and the operation was completed under CT and radiological control.

The use of computer navigation in musculoskeletal oncology allows accurate identification of the local anatomy and can define the extent of the tumour and proposed resection margins. Furthermore, it helps in reconstruction of limb length, rotation and overall alignment after resection of an appendicular tumour.

Cite this article: Bone Joint J 2015;97-B:258–64.

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.

We evaluated the oncological and functional outcome of 18 patients, whose malignant bone tumours were excised with the assistance of navigation, and who were followed up for more than three years. There were 11 men and seven women, with a mean age of 31.8 years (10 to 57). There were ten operations on the pelvic ring and eight joint-preserving limb salvage procedures. The resection margins were free of tumour in all specimens. The tumours, which were stage IIB in all patients, included osteosarcoma, high-grade chondrosarcoma, Ewing’s sarcoma, malignant fibrous histiocytoma of bone, and adamantinoma. The overall three-year survival rate of the 18 patients was 88.9% (95% confidence interval (CI) 75.4 to 100). The three-year survival rate of the patients with pelvic malignancy was 80.0% (95% CI 55.3 to 100), and of the patients with metaphyseal malignancy was 100%. The event-free survival was 66.7% (95% CI 44.9 to 88.5). Local recurrence occurred in two patients, both of whom had a pelvic malignancy. The mean Musculoskeletal Tumor Society functional score was 26.9 points at a mean follow-up of 48.2 months (22 to 79).

We suggest that navigation can be helpful during surgery for musculoskeletal tumours; it can maximise the accuracy of resection and minimise the unnecessary sacrifice of normal tissue by providing precise intra-operative three-dimensional radiological information.

We have reviewed the data from our regional Bone Tumour Registry on patients with osteosarcoma diagnosed between 1933 and 2004 in order to investigate the relationship between survival and changes in treatment. There were 184 patients with non-metastatic appendicular osteosarcoma diagnosed at the age of 18 or under. Survival was calculated using Kaplan-Meier curves, and multivariate analysis was performed using the Cox regression proportional hazards model.

The five-year survival improved from 21% between 1933 and 1959, to 62% between 1990 and 1999. During this time, a multi-disciplinary organisation was gradually developed to manage treatment. The most significant variable affecting outcome was the date of diagnosis, with trends in improved survival mirroring the introduction of increasingly effective chemotherapy. Our experience suggests that the guidelines of the National Institute for Clinical Excellence on the minimum throughput of centres for treatment should be enforced flexibly in those that can demonstrate that their historical and contemporary results are comparable to those published nationally and internationally.