ObjectiveTo investigate the clinical effect of dynamic hip screw (DHS) combined with continuous passive motion (CPM) on intertrochanteric fractures in old patients.MethodsThirty-six old patients with intertrochanteric fractures were treated with DHS internal fixation and began to exercise isometric contraction of quadriceps femoris and to move the big joints of affected limb with CPM machine on the 3rd day after operation.ResultsAll the patients were averagely followed-up for 14 months. According to the effective standard, 26 cases were excellent, 9 cases good and 1 case poor with a 97.2 percentage of fineness. All fractures healed well with no loosening and dislocation of internal fixation. Only one case with type of Evans Ⅲ remained less hip inversion.ConclusionDHS is a good method to treat intertrochanteric fractures of old patients under good preoperative disposal.

AIM: Tissue engineered periosteum fabricated by porcine small intestinal submucosa (SIS) combined with rabbit bone marrow-derived mesenchymal stem cells (BMSCs), are similar to the natural periosteum in the morphology, structure and function. The study was designed to explore the cell attachment in process of constructing tissue-engineered periosteum by different wetting methods to determine the most effective method of fabricating tissue-engineered periosteum. METHODS: The experiment was carried out in the Institute of Orthopedics, the Second Affiliated Hospital of Lanzhou University from September 2005 to March 2007.①Two New Zealand purebred rabbits, 20 days old, were used in this study.②Bone marrow was obtained from healthy rabbits, and BMSCs were isolated by using density gradient centrifugation for culture in vitro. After induction, BMSCs were seeded to SIS wetted with fetal bovine serum (experimental group) and pretreated with phosphate buffered saline (control group), to construct the tissue-engineered periosteum that was cultured for two weeks in vitro. ③The adhesion rates were calculated, and alkaline phosphatase (ALP) activity was detected after seeding. The growth, dissociation and proliferation of the cells were observed by inverted microscope and scanning electron microscope. RESULTS: ①At 5 hours and 12 hours after seeding, the adhesion rates were higher in the experimental group than in the control group [(57.34?2.23)%, (39.16?5.22)%, P