Predictive risk factors for recollapse of cemented vertebrae after percutaneous vertebroplasty: A meta-analysis

BACKGROUND As one of the most common complications of osteoporosis,osteoporotic vertebral compression fracture(OVCF)increases the risk of disability and mortality in elderly patients.Percutaneous vertebroplasty(PVP)is considered to be an effective,safe,and minimally invasive treatment for OVCFs.The recollapse of cemented vertebrae is one of the serious complications of PVP.However,the risk factors associated with recollapse after PVP remain controversial.AIM To identify risk factors for the recollapse of cemented vertebrae after PVP in patients with OVCFs.METHODS A systematic search in EMBASE,MEDLINE,the Cochrane Library,and PubMed was conducted for relevant studies from inception until March 2020.Studies investigating risk factors for the recollapse of cemented vertebrae after PVP without additional trauma were selected for analysis.Odds ratios(ORs)or standardized mean differences with 95%confidence interval(CI)were calculated and heterogeneity was assessed by both the chi-squared test and the I-squared test.The methodological quality of the included studies was assessed according to the Newcastle-Ottawa Scale.RESULTS A total of nine case-control studies were included in our meta-analysis comprising 300 cases and 2674 controls.The significant risk factors for the recollapse of cemented vertebrae after PVP in OVCF patients were fractures located at the thoracolumbar junction(OR=2.09;95%CI:1.30 to 3.38;P=0.002),preoperative intravertebral cleft(OR=2.97;95%CI:1.93 to 4.57;P<0.00001),and solid lump distribution pattern of the cement (OR = 3.11;95%CI: 1.91 to 5.07;P < 0.00001).The analysis did not support that age, gender, lumbar bone mineral density,preoperative visual analogue scale score, injected cement volume, intradiscalcement leakage, or vertebral height restoration could increase the risk forcemented vertebra recollapse after PVP in OVCFs.CONCLUSIONThis meta-analysis suggests that thoracolumbar junction fractures, preoperativeintravertebral cleft, and solid lump cement distribution pattern are associatedwith the recollapse of cemented vertebrae after PVP in OVCF patients.

Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment technologies.Herein,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton processes.Due to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses.This work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.