Objective To investigate the treatment method of osteoporotic refracture after vertebroplasty.Methods One hundred and twenty patients (140 vertebraes) with osteoporotic fractures from January 2010 to January 2011 were selected,12 months after operation,15 cases of refracture (20vertebraes) patients as the research object,11 cases were given bone cement to strengthen treatment,postoperative anti-infection,recovery given a positive rehabilitation exercise instruction ;4 cases were given anti-osteoporosis treatment.Follow-up of 10 months,whether leakage of bone cement and the recovery of anti-osteoporosis treatment were observed.Results Eleven patients with refracture in the process of bone cement injection had no prevertebral venous leakage and disc leakage,none of the patients had bone cement leakage after operation;including 3 cases occurred back pain after injection,the main consideration was surgery influenced the local nerve functions and given analgesic treatment,then pain significantly reduced; 4cases with anti-osteoporosis therapy and recoverd better,no pain and other unsuitable symptom occurred.Postoperative 3 d all of the patients could get out of bed,were discharged on 1 week after operation.All patients were not appear the adverse host reaction of fillers,with no occurrence of refracture.Through visual analog pain scale(VAS) score,VAS score in the 3 d after treatment and end-stage follow-up were significantly lower than before treatment [(3.05 ± 0.55),(0.05 ± 0.15) scores vs.(6.95 ± 0.65) scores],and VAS score at the time of end-stage follow-up was lower than 3 d after treatment,there was significant difference (P ＜0.05).Conclusion Bone cement to strengthen with anti-infection and rehabilitation exercise instruction and anti-osteoporosis in the treatment of osteoporotic refracture after vertebroplasty curative effect,safe and reliable effect,worthy of clinical popularization and application.

Objective To discuss the degenerative factors, the spinal segment distribution, and the mechanism in hyperextension injury of cervical spine. Method Eighty-nine patients with hyperextension injury of cervical spine were retrospectively analyzed by observing the degenerativelesion, the spinal cord segment with high signal in T2WI, and the location of facial trauma. Results Fifty-eight cases showed the disc hemiation which was the most common lesion, followed by 8 cases showing the calcification of the posterior longitudinal ligament. Besides, 7 cases presented the developmental stenosis of spinal canal, and also, 6 cases showed disc hemiation combined with the yellow ligament hypertrophy. The intervertebral level of the spinal cord with high signal in T2WI were distributed as follows:4 cases were at C2/3, of which onesuffered the forehead trauma; 12 cases were at C3/ 4, of which 10 had the forehead trauma, and one had the zygomatic trauma; 12 cases were at C4/5, of which 5 had the forehead trauma, one had both the zygomatic and the forehead trauma, and one had both the forehead and with the lower jaw trauma; 11 cases were at CS/6,of which 3 had the forehead trauma, 3 had the zygomatic trauma, and 2 had the lower jaw trauma. The location of the spinal cord with single high signal in T2WI did not correspond with the intervertebral disc level in 4 cases. For 10 cases the high signal in T2WI was found at two discontinuous segments. For 2 cases the 1 high signal in T2WI was found at over two segments. For 6 cases the high signal in T2WI was found at over three segments. Conclusions Disc hemiation is the most common underlyding factor in cervical hyperextension injury. The spinal level with high signal in T2WI was correlative to the impacted facial site. The shear force at the inflection point with or without the anterior-posterior compression force accounted for the cervical hyperextension injury.

OBJECTIVE: To explore the intervening effects of bone marrow-derived mesenchymal stem cells(BMMSCs) for pulmonary fibrosis of rats exposed to silica dust at different stages. METHODS: Specific pathogen free SD rats were randomly divided into model group,2-week group,4-week group and control group with 6 rats in each group(half males and half females). Rats of the first three groups were one-time endotracheally injected with 0. 5 mL aseptic silica suspension at 30 g/L mass concentration. Rats of control group were injected with 0. 5 mL 0. 90% sodium chloride solution. Rats of 2-week group and 4-week group were injected with 0. 5 mL BMMSCs suspension with cell density was 5 × 10~9/L at 2 weeks and 4 weeks respectively after silica dust exposure,while model group and control group were injected with aseptic 0. 90% sodium chloride solution in the same volume. After that all rats were examined by lung computed tomography(CT) scan,pathological sections were observed,lung coefficient were measured,lung tissue hydroxyproline(HYP) content and serum transforming growth factor β1(TGF-β1) concentration were investigated at the 12 th week after silica dust exposure. RESULTS: Lung CT image showed clean lung field and clear pulmonary parenchyma in control group.Multiple and diffused high density granular shadows of different size and streak/reticular fiber shadows in model group;diffused distribution of very small granular shadows in 2-week group; granular shadows and local reticular fiber shadows in 4-week group,and either the size or the area of granular shadows was smaller than model group. The lung CT value,lung coefficient,lung tissue HYP content and serum TGF-β1 concentration of model group,2-week group and 4-week group were higher than those of control group(P < 0. 05). The lung CT value,lung tissue HYP content and serum TGF-β1 concentration of control group,2-week group,4-week group and model group were elevated in turn(P < 0. 05),while the lung coefficient of model group and 4-week group was higher than that of 2-week group respectively(P < 0. 05).CONCLUSION: BMMSCs could delay pulmonary fibrosis caused by silica dust,and the protective effect is better at early stage than later stage of fibrosis.

OBJECTIVE: To explore the feasibility of dynamic observation and measurement of living silicosis rat model by using small animal positron emission tomography( PET)-computed tomography( CT). METHODS: Specific pathogens free SD rats were divided into model group and control group. The silicosis rat model was established by one-time endotracheal injection of 30 g/L silica suspension,while the control group rats were injected of isopyknic 0. 9% sodium chloride solution. Six rats from each group were randomly selected for CT scan from 1st,2nd,3rd,4th,6th,8th and 12 th week after silica injection using the small animal PET-CT. CT value and standardized uptake value( SUV) of18F-fluorodeoxyglucose were measured. Lung tissue was collected for pathological sections. The levels of hydroxyproline( HYP) of lung tissue and serum transforming growth factor β1( TGF-β1) and interleukin-1( IL-1) were measured.RESULTS: Pathological sections of rats of model group showed inflammatory exudation,inflammation reduced and fibrosis increased with extended time. The results are identical with findings in PET-CT. Lung SUV of rats in model group in the1st-3rd weeks were higher than that in control group in the same time point( P < 0. 05) and decreased by the increasing time during the 1st-4 th weeks of dust injection( P < 0. 05). Lung CT values of model group in the 1st-12 th weeks were higher than that of control group in the same 7 time points( P < 0. 05) and decreased in the 1st-6th weeks and then increased in the 6th-12th weeks by the increasing time of dust injection( P < 0. 05). Lung coefficients and HYP levels of model group in the 7 time points were higher than that of control group in the same 7 time points( P < 0. 05). Lung coefficients decreased in 1st-4th weeks and lung HYP levels increased in 6th-12th weeks with the increasing time of dust injection( P < 0. 05). Excepted of the 3rd and 4th weeks,serum TGF-β1 levels of model group in other 5 time-points were higher than that of control group in the same 5 time points( P < 0. 05) and decreased in the 1st-4th weeks( P < 0. 05)then increased in the 4th-8th weeks( P < 0. 05) by the increasing time of dust injection. Serum IL-1 levels of model group in the 1st-4th weeks were higher than that of control group in the same 4 time points( P < 0. 05) and decreased by the increasing time of dust injection( P < 0. 05) and decreased by the increasing time of dust injection( P < 0. 05).CONCLUSION: Early inflammation and terminal fibrosis of living silicosis rat model could be observed effectively by small animal PET-CT,which can be used as a new approach for dynamic tracing silicosis in rat models.