Massive segmental bone defects in long bones remain a considerable clinical challenge and are a source for significant morbidity and prolonged dysfunction for the patient. We demonstrate the successful use of resorbable polylactide membranes as a scaffold for autologous bone graft in the treatment of a 10cm traumatic femoral bone defect. A 28-year-old male was involved in a motorcycle accident vs. tree at 140k/hr. He sustained a Gustillo grade 3b intercondylar fracture of his right femur, and a 10cm piece of his femoral bone found at the scene was brought to Emergency in a sterile container. He was taken to theatre for debridement and ORIF of the intercondylar fracture, with vacuum dressing cover. Day 5 post injury the patient returned to theatre and the LISS plate was revised to correct the rotation and 3cm shortening. The 10cm cortical defect now present was filled with antibiotic cement (Palacos) and delayed primary closure was performed. Day 21 post injury the cement spacer was removed and replaced with two polylactide membrane tubes, one within the medullary canal and the other around the outside of the bone. The “neocortical” space thus produced was grafted with cancellous autograft mixed with bone morphogenic protein (OP1, Stryker). The remainder of the post-operative course was uncomplicated and the patient was discharged home 5 days later. The patient was reviewed at the 6 week and 3 month mark post injury. The femoral defect demonstrated both radiological and clinical union at the 3 month mark and full weight bearing was permitted. His range of motion at that stage was 5 to 95 degrees with no sign of infection. The use of polylactide membranes as a scaffold in the treatment of segmental long bone defects is an excellent and relatively straightforward technique. Forming a space between the 2 tubes controls cancellous graft to the site of the cortical area where it is required and the polylactide membrane then resorbs over years producing CO2 and water. This case demonstrates that the use of polylactide membranes is safe and effective in the management of segmental long bone defects

The treatment of acute full thickness chondral damage within the knee is a surgical challenge. Frequently used surgical techniques include chondroplasty, micro-fracture and chondrocyte implantation. These procedures give unpredictable functional outcomes and if the formation of neocartilage is achieved it is predominantly composed of type 1 collagen. The TruFit osteochondral plug was designed to provide a scaffold for cell proliferation into full thickness chondral defects. It is a composite polymer composed of polylactide co-glycolide, calcium sulphate and poly-glycolide fibres. It is composed of 2 layers, one with a similar trabecular network to cancellous bone and a superficial layer designed to simulate articular lining. The TruFit bone plug was analysed using micro-computed tomography. Its morphology characteristics, granulometry, mechanical performance and image guided failure were tested as well as numerical modelling to assess the permeability of TruFit. Morphological parameters of the TruFit bone plug compared favourably with those of human tissue. Under load the scaffold exhibited shear bands throughout the composite leading to a failure mechanism similar to cancellous bone. Stress relaxation rates of the scaffolds were greatly decreased under wet conditions, likely due to plasticisation of the scaffold by water. The biomechanical properties of the TruFit bone plugs are a cause for concern. The Scaffolds mechanical performance under load rapidly deteriorates in wet conditions at body temperature (the natural knee environment). This early failure will lead to defects in the articular surface where the plug has been inserted. Clinical data is sparse. This study correlates with work performed by Dockery et al & Spalding et al. These clinical studies have shown that the TruFit implant shows no evidence of bone ingrowth or osteoconductivity. It provides no subchondral support to neocartilage or tissue that was stimulated to form around the defects and surgical sites