Level of evidence (LOE) determination is a reliable tool to assess the strength of research based on study design. Improvements in LOE are necessary for the advancement of evidence-based clinical care. The objectives of this study were to determine if the LOE presented at the Musculoskeletal Tumour Society (MSTS) annual meeting has improved over time and to determine how the LOE presented at MSTS annual meetings compares to that of the Orthopaedic Trauma Association (OTA) annual meetings.

We reviewed abstracts from the MSTS and OTA annual meeting podium presentations from 2005 to 2014. Three independent reviewers evaluated a total of 1222 abstracts for study type and LOE. Changes in the distributions of study type and LOE over time were evaluated by Pearson Chi-Squared test.

There were a total of 577 podium abstracts from the MSTS and 645 from the OTA. Of the MSTS therapeutic studies, 0.5% (2/376) were level I, while 75% (281/376) were level IV. There was a seven-fold higher proportion of level I studies (3.4% [14/409]) and less than half as many level IV studies (32% [130/409]) presented at OTA. There was no improvement in the MSTS LOE for all study types (p=0.13) and therapeutic study types (p=0.36) over the study decade. In contrast, the OTA LOE increased significantly over this time period for all study types (p<0.01). The proportion of controlled therapeutic studies (LOE I through III) versus uncontrolled studies (LOE IV) increased significantly over time at the OTA (p<0.021), but not at the MSTS (p=0.10).

Uncontrolled case series continue to dominate the MSTS scientific program, whereas over the past decade, higher-level studies and more modern study methodology has been employed by members of the OTA.

INTRODUCTION

Allograft reconstruction after resection of primary bone sarcomas has a non-union rate of approximately 20%. Achieving a wide surface area of contact between host and allograft bone is one of the most important factors to help reduce the non-union rate. We developed a novel technique of haptic robot-assisted surgery to reconstruct bone defects left after primary bone sarcoma resection with structural allograft.

We present the results of 15 patients revised with a Compress^® prosthesis secondary to failure of other distal femur reconstruction.

One prosthesis had to be removed because of deep infection. Three patients needed a second surgery due to a vertical crack proximal to the anchor plug at the level of a cortical bone defect. At last follow-up, radiologic evaluation of the entire series showed a mean bone growth ratio higher than did preoperative radiographs. All patients had mainly good or excellent MSTS functional results.

Distal femoral prosthetic replacement with a Compress^® implant in severe cases of bone loosening and instability provides a reliable reconstruction alternative that promotes bone formation. Patients with cortical defects proximal to the anchor plug should be protected with extracortical supports.

The objective of this study was to compare the results of two consecutive series of patients with either intra-medullary uncemented stems (UCS) distal femoral endoprosthetic replacement or the Compress^® (CMP) distal femoral implant.

Patients were divided into two groups: those who received UCS prosthesis (Group-1: 54 patients) and those who received CMP prosthesis (Group-2: 42 patients).The most frequent diagnosis was osteosarcoma. Age and gender were similar both groups.

In Group-1, at a mean follow-up of 144 months, 37 prostheses were still in place. The overall Kaplan-Meier prosthetic survival rates were 79% at five and 62 % at ten years. Most of failures were long term complications. Aseptic loosening was the primary cause of late prosthetic failure. On Cox regression analysis, prosthetic stem diameter under 13mm was a significant negative prognostic factor for prosthetic survival (p=0.016).

In Group-2, at a mean follow-up of 84 months, 36 prostheses were still in place. The overall rate of CMP prosthesis survival was 86% at 5 years. All complications were during the first postoperative year, being femoral fracture the main revision cause.

The patients who retained the prosthesis had mainly good or excellent MSTS functional results in both groups.

Aim: To investigate the possibility of using polymethylmethacrylate (PMMA) bone cement as a delivery vehicle for anti-tumour chemotherapy.

Methods: Doxorubicin was incorporated into PMMA pellets and incubated in physiological medium at 37°C. Release of Doxorubicin from the pellets continued for eight weeks as demonstrated by high performance liquid chromatography (HPLC).

Doxorubicin-containing pellets were incubated with sarcoma cultures at 37°C for 24 hours. A significantly higher cell death rate(as measured by flow cytometry) was seen in the plates exposed to Doxorubicin compared to those exposed only to plain PMMA, indicating that the Doxorubicin released from the cement pellets retained its cytotoxic capability.

PMMA-Doxorubicin cement pellets were implanted in rat tibiae and the animals killed at intervals over three weeks. HPLC analysis showed that this technique produced high concentrations of Doxorubicin adjacent to the implant but negligible systemic levels(heart, kidney, lung, liver).

Four groups of rats had sarcomas established in their tibiae and then treated either by excision of tumour and Doxorubicin/PMMA implantation, excision and plain PMMA implantation, excision only or no treatment. The animals were then observed for tumour regrowth. A survival advantage was demonstrated for those animals treated by tumour excision and Doxorubicin/PMMA implantation.

Conclusion: These experiments demonstrate that PMMA is an effective medium for the delivery of cytotoxic chemotherapy. This method has scope for early translation to the human situation.