1.
[Biomechanical study on a novel injectable calcium phosphate cement containing poly (latic-co-glycolic acid) in repairing tibial plateau fractures].
Zou, H, Ma, X, Tang, C, Li, C, Chen, J, Ye, J
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery. 2013;(7):855-9
Abstract
OBJECTIVE To investigate the biomechanics of a novel injectable calcium phosphate cement (CPC) composited by poly (lactic-co-glycolic acid) (PLGA) combined with double-screw fixation in repairing Schatzker II type tibial plateau fracture, so as to provide the mechanical basis for the clinical minimally invasive treatment. METHODS Ten matched pairs of proximal tibia specimens were harvested from 10 elderly cadavers to prepare Schatzker II type tibial plateau fracture model. Fracture was fixed by forcing injection of CPC (experimental group) or autologous cancellous bone (control group) combined with double-screw fixation. The samples underwent axial compression on MTS 858 material testing machine to measure the load-displacement, the maximum load, and compressive stiffness. RESULTS The novel CPC had good injectable property at room temperature, which could fill in bone defect fully and permeated into the surrounding cancellous bone. The average bone mineral density of tibial metaphysis was (0.639 +/- 0.081) g/cm2 in the experimental group and (0.668 +/- 0.083) g/cm2 in the control group, showing no significant difference (t=1.012, P=0.331). The maximum load in the experimental group [(4 101 +/- 813) N] was significantly higher than that in the control group [(692 +/- 138) N] (t=3.932, P=0.001). The compressive stiffness was (1 363 +/- 362) N/mm in the experimental group and was (223 +/- 54) N/mm in the control group, showing significant difference (t=3.023, P=0.013). CONCLUSION The novel CPC can effectively restore the biomechanical properties of tibilal plateau in repairing Schatzker II type tibial plateau fracture by means of forcing injection combining with double-screw fixation. It could be used as an effective bone substitute in the clinical application.
2.
Meta-analysis comparing sevelamer and calcium-based phosphate binders on cardiovascular calcification in hemodialysis patients.
Zhang, Q, Li, M, Lu, Y, Li, H, Gu, Y, Hao, C, Chen, J
Nephron. Clinical practice. 2010;(4):c259-67
Abstract
BACKGROUND Accelerated cardiovascular calcification often occurs in patients with cardiovascular disease who are on hemodialysis. We performed a meta-analysis to compare the effects of sevelamer hydrochloride and calcium-based phosphate binders on coronary artery calcification, C-reactive protein, alkaline phosphatase and intact parathyroid hormone in patients undergoing hemodialysis. METHODS We used the key words 'sevelamer' and 'Renagel' to retrieve studies from Medline, the Cochrane Library and conference proceedings. The trials searched were evaluated for eligibility and quality, and then the data were abstracted and analyzed. RESULTS We ultimately included 14 studies that enrolled a total of 3,271 patients. There was no difference in coronary artery calcium progression between the calcium and the sevelamer groups. Use of sevelamer, rather than calcium-based phosphate binders, was associated with significantly lower C-reactive protein levels (weighted mean difference (WMD) -1.42; 95% confidence interval (CI) -2.09 to -0.74), higher alkaline phosphatase levels (WMD 22.66; 95% CI 13.81-31.5) and higher intact parathyroid hormone levels (WMD 55.85; 95% CI 14.47-97.24). CONCLUSIONS Treatment with sevelamer did not affect cardiovascular calcification, but there was a trend for lower C-reactive protein levels, higher alkaline phosphatase levels and intact parathyroid hormone levels among sevelamer-treated patients.