ABSTRACT
BACKGROUND: Similar to other prosthesis, metal-metal prosthesis would produce plenty of wear particles and metal ions, mainly presented as cobalt (Co~(2+)) and chromium (Cr~(3+)), which can lead to osteolysis, eventually, result in aseptic loosening. OBJECTIVE: To observe the effect of Co~(2+) and Cr~(3+) ions on the cells viability and expression of RANK in rats m0nocyte-macrophage cells (RAW264.7) in vitro. METHODS: Monocyte-macrophage cells (RAW264.7) were cultured in vitro, and then the cells were exposed to Co~(2+) and Cr~(3+) ions. The cell viability was assured by MTT test and the level of RANK Mrna was detected by semi-quantitative RT-PCR at different times. RESULTS AND CONCLUSION: Compared to the control group, MTT test demonstrated that Co~(2+) and Cr~(3+)ions could decrease the cell activity of monocyte-macrophage cells obviously. When the cells were exposed to Co~(2+) Cr~(3+) ions, compared to the control group, the Mrna expression of RANK of the metal ions group was increased at 12 hours (P < 0.05), reached its peak level at 24 hours (P < 0.05), and decreased at 48 hours than that of 24 hours (P < 0.05). The results revealed that metal ions have a cytotoxic effect on monocyte-macrophage cells, stimulate the expression of RANK, and have the potential of facilitating monocyte-macrophages cells transform into osteoclast-like cells.
ABSTRACT
[Objective]To investigate the effect of individualized exercises rehabilitation after tibial fracture operation.[Method]A total of 161 cases of tibial plateau fractures from Jan.2003 to Dec.2007 were analyzed retrospectively.In control group,81 patients received traditional rehabilitation.In rehabilitation group,80 patients received individualized rehabilitation exercises guided by Safety Assessment for Orthopaedic Rehabilitation.All cases were followed up and received X-ray exam.HSS (hospital for special surgery knee-rating score) was used to assess the knee function at 3,6,12 months after surgery.[Result]All patients were followed up for 2 years.Internal fixation broken was found in 2 cases in control group,in 3 cases in rehabilitation group.According to HSS scoring system,the good-to-excellent rates of knee joint at 6,12 months postoperatively in rehabilitation group were 77%,87%,significantly higher than 56%,66% in control group (P