Efficacy comparison of percutaneous pedicle instrumentation combined with vertebral fracture fixation or vertebral augmentation for treatment of osteoporotic thoracolumbar fractures in elderly patients / 中华创伤杂志

Objective To compare the outcomes of percutaneous pedicle instrumentation combined with vertebral augmentation or vertebra pedicle instrumentation for treatment of osteoporotic thoracolumbar fractures (OVCF) in elderly patients.Methods A retrospective case cohort study was conducted on 62 patients with OVCF manifesting non-neurological symptoms treated from January 2009 to January 2012.There were 22 males and 30 females,with a mean age of 61.3 years (range,55 to 70 years).Fracture level was T11 in 8 patients,T12in 20,L1 in 22 and L2 in 12.Treatments included percutaneous pedicle instrumentation combined with vertebral fracture fixation in 36 patients (Group A) and percutaneous pedicle instrumentation combined with vertebral augmentation in 26 patients (Group B).Operation time,intraoperative blood loss,anterior vertebral body height,sagittal Cobb angle and visual analogue score (VAS) were compared between the two groups.Results All patients were followed up for average 46.5 months (range,36 to 58 months).Operation time in Group A [(82.6 ±16.2) min] was shorter than that in Group B [(96.8 ± 20.6) min] (P ＜ 0.05).Blood loss in Group B [(40.5 ± 10.2) ml] was less than that in Group A [(52.2 ± 15.5) ml] (P ＜ 0.05).Before operation and 3 days and 1 year after operation,the anterior vertebral body height and sagittal Cobb angle in Group A showed no significant differences compared to Group B (all P ＞ 0.05).At the final follow-up,the ratio of anterior vertebral height and Cobb angle in Group B [(87.8 ± 2.5) ％,(7.8 ± 3.5) °] were better than these in Group A [(82.6 ±3.2)％,(9.1 ± 1.8)°] (P＜0.05).VAS showed no statistical significance between the two groups before and after operation (P ＞ 0.05).Bone cement leakage was seen in four patients in Group B.During the perioperative period,there were 3 patients with lung infection in Group A and 1 patient with lower limb deep vein thrombosis in Group B.No implant failure occurred in both groups.Conclusion Both procedures are effective in treating elderly patients with OVCF,but percutaneous pedicle instrumentation combined with vertebral augmentation is associated with better results in maintaining vertebral height and preventing kyphosis.

Correlations between lipid ratio/oxidative stress status in COPD patients and pulmonary hypertension as well as prognosis / 中南大学学报(医学版)

To investigate the correlations between lipid ratio/oxidative stress status in chronic obstructive pulmonary disease (COPD) patients and pulmonary hypertension as well as the prognosis.
 Methods: A total of 120 patients with COPD were randomly selected and served as the COPD group and 30 healthy persons were selected as the control group. The ratios of low density lipoprotein (LDL)/high-density lipoprotein (HDL), triglyceride (TG)/HDL and total cholesterol (TC)/HDL were measured. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) level in the control group and COPD patients were detected. Pulmonary hypertension incidence and 3-year survival rate for COPD patients were statistically analyzed. Spearman rank correlation method was used to analyze relationship between lipid ratio /oxidative stress status and pulmonary hypertension.
 Results: Compared with control group, the ratios of LDL/HDL, TG/HDL and TC/HDL, and the serum MDA level in the COPD group were increased, while the serum SOD and T-AOC level in the COPD group were decreased; compared with stable period, lipid ratios and MDA levels in the acute period were elevated, while serum SOD and T-AOC levels were reduced (P<0.05). Pulmonary hypertension incidence and 3-year survival rates in the COPD group were 56.67% and 81.67% respectively; the lipid ratios and serum MDA levels in COPD patients with pulmonary hypertension were elevated compared with that in COPD patients without pulmonary hypertension; the serum SOD and T-AOC levels in COPD patients with pulmonary hypertension were reduced compared with that in patients without pulmonary hypertension (P<0.05). Spearman rank correlation analysis showed that ratios of LDL/HDL, TG/HDL and TC/HDL, and the serum MDA levels in COPD patients were positively correlated with 3-years pulmonary hypertension incidence (r=0.752, 0.748, 0.752, 0.748; P<0.05), and negatively correlated with 3-years survival rate (r=-0.722, -0.751, -0.736, -0.748; P<0.05); serum SOD and T-AOC levels in COPD patients were negatively correlated with 3-years pulmonary hypertension (r=-0.711, -0.734; P<0.05), and positively correlated with 3-year survival rate (r=0.726, 0.733; P<0.05). 
 Conclusion: Blood lipid ratio and oxidative stress levels in COPD patients are elevated while antioxidant abilities were attenuated. The lipid ratio and oxidative stress status in COPD patients is closely related to the prognosis of pulmonary hypertension. Therefore, blood lipid ratio and oxidative stress status may be used in evaluation of pulmonary hypertension and prognosis for COPD patients.

Gradient biocomposite with hydroxyapatite/zirconia for repair of cyno-bone defects / 中华创伤杂志

Objective To evaluate the bonding condition of hydroxyapatite (HA)/zirconia ( ZrO2 ) composite and bone interface and the ability of HA/ZrO2 in repair of bone defects.Methods Bone defect models were established in the lumbar vertebral body of 24 Beagle dogs and were implanted with HA/ZrO2 gradient composite (Group A ),HA/ZrO2 unilayer composite (Group B ),pure ZrO2 (Group C) and pure HA (Group D) successively.Dogs were sacrificed and lumbar vertebral specimens were harvested 6,12,16 weeks postoperatively and before the sacrifice at postoperative 6 and 12 weeks,the dogs were intramuscularly administered of quadracycline for fluorescence labeling.The interface bonding and repair of bone defects were observed through X-ray films,histomorphology and biomechanical test.Results The X-ray films displayed that the Group A achieved more formation of osteotylus and better repair of bone defects with the extension of the implantation period,followed by the Groups B and D and that the Group C had relatively worse results.Histomorphology study showed that the fluorescence labeling was enhanced gradually from 6 to 12 weeks in the Group A,with its growth from the edge of the implanted material to the inner part and its tight adhesion to the material,indicating active osteogenesis and massive bone formation.While the fluorescence labeling of the Groups B,C and D centered in the edge of implanted materials without presence in the material inner part.The mineralization rate of the four materials at 6 and 12 weeks had significant differences ( P ＜ 0.05).Synostosis rates at 6,12 and 16 weeks were the highest in the Group A,with the rate of up to (90.26 ±3.82) ％ at 16 weeks (P ＜0.05 ).Biomechanical test showed the maximum shear strengths at 6,12,16 weeks in the Group A were (2.64±0.16) MPa,(2.95 ±0.19) MPa and (3.45 ±0.23) MPa respectively (P＜0.05).Conclusion HA/ZrO2gradient biocomposite bonds well with the bone and possesses good repair ability for bone defects and hence is an ideal novel material for bone defect reconstruction.