The burden of osteoporosis (OP), and its accompanied low energy fractures, is ever increasing. Targeted therapies are under development to stem the tide of the disease, with microRNAs identified as biomarkers and potential targets. Assessing the functional capacity of bone marrow mesenchymal stromal cells (BMSC) from patients with low energy neck of femur fractures (NOF) will identify the expected outcomes to be achieved from new, targeted osteogenic therapies. Two patient groups were assessed; low energy NOF and osteoarthritic. Bone marrow aspirates were taken at time of arthroplasty surgery. The adherent fraction was cultured and assessed by flow cytometry, microRNA expression and differentiation functionality. Both patient groups demonstrated characteristic extracellular markers of BMSCs. 3 key markers were significantly reduced in their expression in the NOF group (CD 90, 13, 166 P=0.0286). Reduced differentiation capacity was observed in the NOF group when cultured in osteogenic and adipogenic culture medium. 105 microRNAs were seen to be significantly dysregulated, with microRNAs known to be crucial to osteogenesis and disease process such as osteoporosis abnormally expressed. This data demonstrates the impaired functional capacity of BMSCs and their abnormal microRNA expression in patients who suffer a low energy NOF. Future targeted therapies for OP must address this to maximise their restorative effect on diseased bone. The important role microRNAs can play as biomarkers and target sites has been further reinforced

In biomaterial engineering the surface of an implant can influence cell differentiation, adhesion and affinity towards the implant. Increased bone marrow derived mesenchymal stromal cell (BMSC) differentiation towards bone forming osteoblasts, on contact with an implant, can improve osteointegration. The process of micropatterning has been shown to improve osteointegration in polymers, but there are few reports surrounding ceramics. The purpose of this study was to establish a co-culture of BMSCs with osteoclast progenitor cells and to observe the response to micropatterned zirconia toughened alumina (ZTA) ceramics with 30 µm diameter pits. The aim was to establish if the pits were specifically bioactive towards osteogenesis or were generally bioactive and would also stimulate osteoclastogenesis that could potentially lead to osteolysis. We demonstrate specific bioactivity of micropits towards osteogenesis with more nodule formation and less osteoclastogenesis. This may have a role when designing ceramic orthopaedic implants