Aim

Infections in long bones can be divided in osteitis, osteomyelitis and septic non-unions. All are challenging situations for the orthopaedic surgeon. Treatment is a mix with debridement, radical resection of infected tissue, void filling with different types of products, and antibiotic therapy of different kinds. In cavitary bone defects, bioglasses such as BAG-S53P4 have given good results in early or mid-term follow-up. Results of such treatment in segmental bone defects remain unknown. The goal of our study was to evaluate efficacity of active bioglass BAG-S53P4 in septic segmental bone defects.

Objectives

One commonly used rat fracture model for bone and mineral research is a closed mid-shaft femur fracture as described by Bonnarens in 1984. Initially, this model was believed to create very reproducible fractures. However, there have been frequent reports of comminution and varying rates of complication. Given the importance of precise anticipation of those characteristics in laboratory research, we aimed to precisely estimate the rate of comminution, its importance and its effect on the amount of soft callus created. Furthermore, we aimed to precisely report the rate of complications such as death and infection.

Introduction

Osteoporosis is a metabolic disease of the bone responsible for a loss of bone resistance and an increase in fracture risk. World Health Organization (WHO) estimations are about 6.3 millions of femoral neck fractures in the world by 2050. These estimations make osteoporosis a real problem in term of public health.

Knowledge in biological tissues mechanical behaviour and its evolution with age are important for the design of diagnosis and therapeutic tools. From the mechanical aspect, bone resistance is dependent on bone density, bone architecture and bone tissue quality. If the importance of bone density and bone architecture has been well explored, the bone tissue quality still remains unstudied because of the lack of biomechanical tools suitable for testing bone at this microscopic dimension.

Therefore the goal of this study is to estimate the osteoporotic cancellous bone tissue mechanical behaviour at its microscopic scale, using an approach coupling mechanical assays and digital reconstruction.

Purpose of the study: Secondary chondrosarcoma is rare (1% of malignant bone tumours). Most cases develop from solitary exostosis or concern an exostosis disease. Localisations predominate in the girdles. Management is difficult and no consensus has been reached. The purpose of this study was to present a series of 25 secondary chondrosarcomas in order to improve diagnostic and therapeutic management.

Material and methods: This was a retrospective analysis of 25 cases of secondary chondrosarcoma (10 on solitary exostosis and 15 on exostosis disease) treated by one surgical team from 1970 to 2008. The epidemiological features, clinical signs, radiographic findings, type of treatment and outcome at last follow-up were analysed for the two groups.

Results: Patients with secondary chondrosarcoma were 10 to 20 years young than those with primary chondrosarcoma. There were an equivalent number of men and women and the predominant sites involved flat bones in both groups. The radiographic signs of sarcomatous degeneration most widely observed included heterogeneous calcifications, irregular contours, and soft tissue invasion. Tumours were generally well differentiated. The rate of local recurrence after surgery was 15% at five years and 20% at ten years. Mortality was 2% at five years and 5% at ten years. Most of the deaths occurred after local recurrence. Metastases were identified in four patients after the initial resection. The rate of local recurrence was lower after wide surgical resection.

Discussion: The real objective with secondary chondrosarcoma is to ensure a regular effective follow-up of these patients with a known risk of recurrence (exostosis disease) in order to recognise early signs of sarcomatous degeneration. One of the most reliable signs is recent development of unusual pain on a known exostosis. Education of at-risk patients is crucial and should enable early screening and detection.

Conclusion: Secondary chondrosarcoma occurs 10 to 20 years earlier than primary sarcoma and generally involves the girdles. Outcome and management practices are similar to primary chondrosarcoma. The most important issue is to ensure good patient follow-up in order to enable early diagnosis in patients at risk.