Alloys of titanium, aluminium, vanadium, iron and other metals are traditional materials used in bone tissue surgery. The anchorage of the metallic materials into the surrounding tissue depends of their mechanical and other physical and chemical properties. The integration of metallic material with the surrounding tissue can be markedly improved by appropriate physicochemical surface properties of the material, such as roughness, topography, wettability or presence of certain chemical functional groups. In the present study the first step the surface roughness of samples of pure Ti or Ti6Al4V alloy. In order to influence the adhesion, growth and presence of bone differentiation markers in human osteoblast-like MG 63 cells, we modified as machining or subsequent polishing by diamond paste was performed. In addition, we investigated the interaction of these cells with a newly developed material for construction of bone-anchoring parts of bone implants. These tested materials were treated either with electro-erosion or plasma-spraying with Ti. After the cells seeding (MG63, human osteoblast-like cells of the line MG 63, derived from osteosarcoma of a 13-year-old boy, on different surfaces, the basic parametrs of adhesion and the viability of bone cells were detected, the cell were analysed and cultered for 1–8 days, during 3 different time intervals(expl.1. 4. and 7 day). Cells number, were detected and analyzed in a ViCell XR analyzer. The concentration of molecules participating in cell adhesion, osteoblastic differentiation, was determined semi-quantitatively by the enzyme-linked immunosorbent assay (ELISA) in cell. In addition we performed a reconstruction curve of population density of human osteoblast-like MG 63 cells on day 1, 4 and 8. including calculation of doubling time(DT)in human osteoblast-like MG 63 cells grown on metallic materials with different surface treatments. From the tested surfaces Ti Alloys electroerosion surfaces seem promising materials. They show the best osteointegration parameters in vitro. Nevertheles further in vivo experiments must be performed prior to clinical use.

Aims: In spite of approved methods of osteosynthesis of proximal femoral fractures using modern implants stabilisation still may fail especially in unstable osteoporotic fractures which is a cause of revision surgeries and unsatisfactory functional results. The goal of our study was to determine predisposing factors of failure of either DHS or PFN osteosynthesis with respect to the degree of osteoporosis. At the same time we evaluated clinical results one year after surgery and evaluated occurrence of further osteoporotic fractures.

Methods: Within the framework of a research plan (2005–2009) patients with low energy fractures of trochanteric area with qCT proven osteoporosis have been randomised. Unstable intertrochanteric fractures were operated by either DHS or PFN osteosynthesis after adequate reduction. During surgery one bone sample was taken from the femoral head prior to insertion of head screw located at the tip of the screw and the second sample was taken from iliac crest. Samples from the femoral head were examined by histomorphometry. Relationship between histomorphometry and migration of osteosynthetic material was evaluated. After surgery patients were examined in osteology department including DEXA and received appropriate treatment of osteoporosis. Orthopaedic follow up was performed 6 weeks, 3, 6 and 12 months after surgery when patients were evaluated by Harris hip score. Results were evaluated statistically.

Results: From September 1. 2005 to August 31. 2006 55 patients with unstable intertrochanteric fractures had been randomised. DHS was used in 26 patients and PFN in 29 patients. The average age of the patients was 75,6 years. Only patients who were able to sign informed consent were elegible for randomisation. The average qCT T-score was −3,2 and the qCT Z-score was −1,1. In addition to osteoporosis osteomalacia was proven histologically in one patient. Secondary osteoporosis was proven in 15 per cent of all patients. 49 patients were examined 1 year after operation. Failure of osteosynthesis was observed in four cases (7,3 per cent, 2x DHS and 1x PFN cut out phenomenon, 1 case of PFN head screw migration). Migrating PFN screw was removed. There were no other revision surgeries. The average qCT T-score in patients with failure of osteosynthesis was −4,3, Z-score −2,1. The average HHS one year after surgery was 67,3.

Conclusions: In patients with proven osteoporosis in spite of correct surgical technique risk of osteosynthesis failure is increased. Optimized surgical techniques and implants may still improve surgical results in patients with severe osteoporosis (qCT T-score lower than −4).