ObjectiveTo investigate the value of smart phone Scoliometer software in obtaining optimal lumbar lordosis (LL) during L4-S1 fusion surgery. MethodsBetween November 2014 and February 2015, 20 patients scheduled for L4-S1 fusion surgery were prospectively enrolled the study. There were 8 males and 12 females, aged 41-65 years (mean, 52.3 years). The disease duration ranged from 6 months to 6 years (mean, 3.4 years). Before operation, the pelvic incidence (PI) and Cobb angle of L4-S1 (CobbL4-S1) were measured on lateral X-ray film of lumbosacral spine by PACS system; and the ideal CobbL4-S1 was then calculated according to previously published methods [(PI+9°)×70%]. Subsequently, intraoperative CobbL4-S1 was monitored by the Scoliometer software and was defined as optimal while it was less than 5° difference compared with ideal CobbL4-S1. Finally, the CobbL4-S1 was measured by the PACS system after operation and the consistency was compared between Scoliometer software and PACS system to evaluate the accuracy of this software. In addition, value of this method in obtaining optimal LL was validated by comparing the difference between ideal CobbL4-S1 and preoperative one with that between ideal CobbL4-S1 and postoperative one. ResultsThe CobbL4-S1 was (36.17±1.53)° for ideal one, (22.57±5.50)° for preoperative one, (32.25±1.46)° for intraoperative one measured by Scoliometer software, and (34.43±1.72)° for postoperative one, respectively. The observed intraclass correlation coefficient (ICC) was excellent [ICC=0.96, 95% confidence interval (0.93, 0.97)] and the mean absolute difference (MAD) was low (MAD=1.23) between Scoliometer software and PACS system. The deviation between ideal CobbL4-S1 and postoperative CobbL4-S1 was (2.31±0.23)°, which was significantly lower than the deviation between ideal CobbL4-S1 and preoperative CobbL4-S1 (13.60±1.85)° (t=6.065, P=0.001). ConclusionScoliometer software can help surgeon obtain the optimal LL and deserve further dissemination.
ObjectiveTo analyze the phasic changes of bone mass, bone turnover markers, and estrogen levels at different time points after glucocorticoid (GC) intervention in rat and their correlation. MethodsThirty-four female 3-month-old Sprague Dawley rats were randomly divided into the following 3 groups:baseline group (n=6), dexamethasone (DXM) group (n=14), and control group (n=14). Rats were injected with DXM at the dose of 0.75 mg/kg, twice a week for 12 weeks in DXM group, with salt solution lavage in control group, and no treatment was given in baseline group. The body mass, adrenal weight, and uterus weight were measured. Bone mineral density (BMD), bone mineral content (BMC), and bone area (BA) of lumbar vertebral and femurs were detected by dual energy X-ray absorptiometry. Meanwhile, the serum levels of N-terminal propeptide of type I procollagen (PINP), C-terminal cross-linking telopeptide of type I collagen (β-CTX), and estrogen levels were determined by ELISA before experiment in baseline group and at 4, 8, and 12 weeks after experiment in control and DXM groups. At last, the correlation was analyzed among body weight, BMD, PINP, β-CTX, estrogen levels, and GC intervention duration of DXM group. ResultsThe body mass, adrenal weight, and uterus weight in DXM group were significantly lower than those in baseline group and control group at all the time points (P<0.05). The levels of PINP and β-CTX elevated slowly in DXM group, significant difference was found at 12 weeks (P<0.05), but no significant difference at the 4 and 8 weeks (P>0.05) when compared with those in baseline group and control group. The estrogen level in DXM group was significantly lower than that in baseline group and control group at all the time points (P<0.05). BMD, BMC, and BA of lumbar vertebral and femurs in DXM group were significantly lower than those in control group at all the time points after GC intervention (P<0.05). Loss of bone mass of L2 and femoral trochanteric region in DXM group was the lowest of all ranges of interest (ROIs). BMC and BA of lumbar vertebrae and BA of femoral shaft in DXM group at 4 weeks were significantly lower than those in baseline group (P<0.05). But there was no significant difference in BMD, BMC, and BA of other lumbar vertebrae and femurs' ROIs between DXM group and baseline group at all the time points (P>0.05). After GC intervention, BMD of lumbar vertebrae and femurs had negative correlation with PINP and β-CTX (P<0.05) and positive correlation with estrogen level (P<0.05). ConclusionThe bone mass decreases rapidly at the early stage after GC intervention and then maintains a low level with time, the levels of bone turnover markers show a progressive increase, and the estrogen levels show a decrease trend. In addition, body weight, the levels of bone turnover markers and estrogen are associated with the change of bone mass.