Animal Modelling of Lumbar Corpectomy and Fusion and in vivo Growth of Spine Supporting Bone by Titanium Cage Implants: An Experimental Study

In this study a lumbar spinal fusion animal model is established to assess the effect of spinal fusion cage,and explore theminimum area ratio of titanium cage section to vertebral section that ensures bone healing and biomechanical property.Lumbarcorpectomy was conducted by posterolateral approach with titanium cage implantation combined with plate fixation.Titaniumcages with the same length but different diameters were used.After implantation of titanium cages,the progress of bone healingwas observed and the bone biomechanical properties were measured,including deformation and displacement in axial compression,flexion,extension,and lateral bending motion.The factors affecting the in vivo growth of spine supporting body wereanalyzed.The results show that the area ratio of titanium cage section to vertebral section should reach 1/2 to ensure the bonehealing,sufficient bone intensity and biomechanical properties.Some bone healing indicators,such as BMP,suggest that there isa relationship between the peak time and the peak value of bone formation and metabolism markers and the bone healing strength.

Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in Chinese postmenopausal women with osteoporosis: a multi-center, randomized, placebo-controlled clinical trial

Background Raloxifene has been approved for prevention and treatment of postmenopausal osteoporosis in Caucasian women. It also has some positive effects on serum lipids in Caucasians. The objective of this study was to determine the effect of raloxifene hydrochloride on lumbar spine and total hip bone mineral density (BMD), bone metabolism, and serum lipids in Chinese postmenopausal women with osteoporosis.Methods This was a multi-center, randomized, double-blind, placebo-controlled clinical trial in which 204 postmenopausal Chinese women with osteoporosis were assigned to receive raloxifene (60 mg) or placebo treatment daily for 12 months. BMD, serum bone metabolism markers, and serum lipids were measured before and after drug administration. BMD was measured by Dual-Energy X-Ray Absorptiometry (DEXA) and bone metabolism markers were analyzed by one-step enzyme-linked immunosorbent assay. Serum lipids were measured by enzymatic analysis.Results At the end of the 12-month study, lumbar spine BMD increased in both groups with a mean increase of (3.3±4.8) % in the raloxifene group and (1.0±4.9) % in the placebo group (P<0.001). There was a mean increase in total hip BMD of (1.4±4.8) % in the raloxifene group and a mean decrease of (0.9±5.0) % in the placebo group (P<0.001). No subject in the raloxifene group had a new vertebral fracture and 5 placebo subjects had new fractures (P>0.05). In the raloxifene group, the median decreases in the biochemical markers of bone metabolism serum osteocalcin and C-telopeptide were 41.7% and 61.5%, respectively. These changes were statistically significant compared with those in the placebo group (10.6% and 35.6%, P<0.001, respectively). Both total cholesterol and low-density lipoprotein cholesterol decreased significantly in the raloxifene group compared with those in the placebo group (P<0.001, respectively) and there was no significant effect of raloxifene on high-density lipoprotein cholesterol and triglycerides compared with placebo. Conclusions Raloxifene 60 mg/d for 12 months significantly increases lumbar spine and total hip BMD, significantly decreases bone turnover, and has favourable effects on serum lipids in Chinese postmenopausal women with osteoporosis.

Bone Metabolic Markers in Patients with Obstructive Sleep Apnea Syndrome

Background： Obstructive sleep apnea syndrome （OSAS） is prevalent in obesity and is associated with many metabolic abnormalities. The relationship between OSAS and bone metabolism is still unclear. The aim of this study was to investigate the relationship between the severity of OSAS and bone metabolic markers. Methods： A total of 119 obese males were enrolled in this study in spring months from 2015 to 2017. All candidates underwent polysomnography, and their bone mineral density （BMD） and the serum levels of total procollagen type 1 N-tenninal propeptide （t-P I NP）, N-terminal midfragment ofosteocalcin （N-MID）, [3-C-terminal telopeptide of type 1 collagen （β-CTX）, vitamin D （VD）, and parathyroid hormone （PTH） were measured. The analysis of variance and Pearson correlation analysis were performed for data analyses. Results： No significant differences in the mean values of BMD were observed among the obesity, mild-to-moderate OSAS, and severe OSAS groups; and the serum levels oft-P1NP and [3-CTX in the severe OSAS group were significantly higher than those in the obesity group （48.42 ±23.78 ng/ml vs. 31.98 ± 9.85 ng/ml, P 〈 0.001 ; 0.53 ± 0.24 ng/ml vs. 0.41 ±0.13 ng/ml, P 0.011, respectively）. The serum level of VD in the obesity group was significantly higher than those in the mild-to-moderate and severe OSAS groups （both P 〈 0.001 ）, and decreased as the severity of OSAS increased （P 〈 0.001）. The serum level of PTH in the severe OSAS group was significantly higher than those in the obesity and mild-to-moderate OSAS groups （both P 〈 0.001 ）. The results of correlation analysis indicated that the level of apnea-hypopnea index （AHI） was correlated with the levels oft-P1NP （r = 0.396, P 〈 0.001 ）, VD （r = 0.404, P 〈 0.001 ）, and PTH （r = 0.400, P 〈 0.001 ）, whereas the level of minimum 02 saturation （SaO2min） was correlated with the levels ofVD （r = 0.258, P=0.016） andPTH（r= 0.376, P〈0.001）. Conclusions： The levels of bone resorption and formation markers in patients with severe OSAS were significantly increased compared to obese men, and the severity of OSAS was correlated with the serum levels of t-P1NP, VD, and PTH.

Correlations of single photon emission computed tomography joints scan and bone metabolic markers in active rheumatoid arthritis

Objective To explore the correlation between quantitative value of joint bone scan by single photon emission computed tomography(SPECT)and serum bone metabolic markers in patients with active rheumatoid arthritis(RA).Methods Clinical data of 60 newly diagnosed RA patients were retrospectively collected in Department

Clinical update of pulsed electromagnetic fields on osteoporosis

Objective To understand the effects of low-frequency pulsed electromagnetic fields （PEMFs） on chronic bony pain, bone mineral density （BMD）, bone strength and biochemical markers of bone metabolism in the patients of osteoporosis. Data sources Using the key words “pulsed electromagnetic fields” and “osteoporosis”, we searched the PubMed for related studies published in English from January 1996 to December 2007. We also searched the China National Knowledge Infrastructure （CNKI） for studies published in Chinese from January 1996 to December 2007.Study selection Inclusion criteria： （1） all articles which referred to the effects of low-frequency pulsed magnetic fields on osteoporosis either in primary osteoporosis or secondary osteoporosis; （2） either observational studies or randomized controlled studies. Exclusion criteria： （1） articles on experimental studies about osteoporosis; （2） repetitive studies; （3） case reports; （4） meta analysis.Results Totally 111 related articles were collected, 101 of them were published in Chinese, 10 were in English. Thirty-four were included and the remaining 84 were excluded.Conclusions Low-frequency PEMFs relieves the pain of primary osteoporosis quickly and efficiently, enhances bone formation and increases BMD of secondary osteoporosis. But the effects of PEMFs on bone mineral density of primary osteoporosis and bone resorption were controversial.