Abstract. Distraction Osteogenesis (DO) for the management of bone defects in long bones is an established technique. Problems with bone regeneration are a common occurrence and literature is full of different modalities to enhance regenerate formation and quality. Strontium Ranelate (SR) has a dual mode of action and enhances bone formation in addition to decreasing osteoclastic activity. Due to this dual mode of action as well as ease of administration in a suspension form, it makes an ideal drug in scenarios where realignment of bone homeostasis towards positive bone balance is desirable. We studied the relationship of administration of SR with rate of regenerate progression, docking site union and complications associated with bone transport in 48 patients undergoing bone transport for management of bone defects. The findings of our retrospective observation study indicated that compliant use of SR was associated with good regenerate progression, decreased problems with docking site union and decreased the need for additional interventions

Osteoporosis is a major healthcare burden, responsible for significant morbidity and mortality. Manipulating bone homeostasis would be invaluable in treating osteoporosis and optimising implant osseointegration. Strontium increases bone density through increased osteoblastogenesis, increased bone mineralisation, and reduced osteoclast activity. However, oral treatment may have significant side effects, precluding widespread use. We have recently shown that controlled disorder nanopatterned surfaces can control osteoblast differentiation and bone formation. We aimed to combine the osteogenic synergy of nanopatterning with local strontium delivery to avoid systemic side effects. Using a sol-gel technique we developed strontium doped and/or nanopatterned titanium surfaces, with flat titanium controls including osteogenic and strontium doped media controls. These were characterised using atomic force microscopy and ICP-mass spectroscopy. Cellular response assessed using human osteoblast/osteoclast co-cultures including scanning electron microscopy, quantitative immunofluorescence, histochemical staining, ELISA and PCR techniques. We further performed RNAseq gene pathway combined with metabolomic pathway analysis to build gene/metabolite networks. The surfaces eluted 800ng/cm2 strontium over 35 days with good surface fidelity. Osteoblast differentiation and bone formation increased significantly compared to controls and equivalently to oral treatment, suggesting improved osseointegration. Osteoclast pre-cursor survival and differentiation reduced via increased production of osteoprotegrin. We further delineated the complex cellular signalling and metabolic pathways involved including unique targets involved in osteoporosis. We have developed unique nanopatterned strontium eluting surfaces that significantly increase bone formation and reduce osteoclastogenesis. This synergistic combination of topography and chemistry has great potential merit in fusion surgery and arthroplasty, as well as providing potential targets to treat osteoporosis

Introduction. In total hip arthroplasty ceramic on ceramic bearing couples are used more and more frequently and on a wordwide basis. The main reason of this choice is reduction of wear debris and osteolysis. The tribological properties and the mechanical behaviour of the implanted ceramic must remain the same throughout the patient's life. The aim of this study was to evaluate the resistance of Alumina Matrix Composite to environmental degradation. Material and method. The alumina matrix composite or BIOLOX ® delta is manufactured in Germany by CeramTec. It is made up of 80 vol.% Al2O3, 17 vol.% Yttria Stabilized ZrO2 and 3vol.% strontium aluminate platelets. The zirconia grains account for 1.3 mol.% of the Yttria content. Accelerated aging tests in water steam at 142°C, 134°C, 121°C, and 105°C were performed to evaluate the aging kinetics of the composite. X-ray diffraction was used to determine the monoclinic phase content on the material surface. Phase transformation is associated with weakness and increase in roughness of zirconia ceramic implants. Results. The data below shows average monoclinic contents before and after aging in water vapour according to the ISO standard test (134°C, 2 bars water steam, 10 h) on the surface and inside the 28 mm taper(12/14 taper) femoral ball heads manufactured in alumina ceramic composite. There are precisions concerning the roughness and the load to failure before and after aging concerning 28mm diameter heads. Before Aging 13%+/-3% of Monoclinic content. After 10 H at 134°C23%+/-3% of Monoclinic content the roughness of the polished surface remain the same (5nm+/− 2). The load to failure of 28 mm heads before aging is 76 kN +/− 5kN, and 72 kN +/− 5kN after aging. The results show that although a rise in monoclinic content is predictable after long aging duration in vivo, the impact of the transformation is quite different to monolithic zirconia. A zirconia femoral head exhibits an important increase of roughness from 2 nm to more than 50 nm when submitted to the same duration of ageing. Other tests with hip simulators under severe micro separation have been done to analyse the impact of aging on wear performance. The main wear zone on femoral heads underwent a phase transformation from tetragonal to monoclinic (23% monoclinic) at 5 milion cycles duration without any change in roughness after 5Mc duration. Conclusion. This experimental testing program has enabled a prediction for the long-term in vivo environmental resistance of prostheses made out of Alumina Matrix Composite. The substantial improvement in mechanical properties and the excellent wear behaviour, even under severe microseparation conditions has been clinically confirmed. Today more than 960,000 ceramic ball heads and more than 450 000 ceramic inserts made of the alumina matrix composite have been implanted. Additionally, due to enhanced mechanical behaviour, new applications in orthopaedics are possible

Aims

Bone health assessment and the prescription of medication for secondary fracture prevention have become an integral part of the acute management of patients with hip fracture. However, there is little evidence regarding compliance with prescription guidelines and subsequent adherence to medication in this patient group.