BACKGROUND:Computer-assisted navigation technique has been widely applied in spinal surgery, but there is stil lack of systematic reviews on this technique in lumbar pedicle screw fixation.
OBJECTIVE:To evaluate the application of computer-assisted navigation technique in lumbar pedicle screw fixation.
METHODS:Databases such as PubMed, Embase and China journal ful-text database CNKI were searched for articles about computer-assisted navigation in lumbar pedicle screw fixation, and related studies and literatures were hand-searched as wel , and then insertion accuracy, intraoperative blood loss, operative time consumption and rate of insertion-related complications between computer-assisted navigation technique group and conservative technique group were compared.
RESULTS AND CONCLUSION:Final y 7 studies which met the inclusion criteria were included with 784 patients and 4 101 lumbar pedicle screws in total. Meta-analysis indicated that malposition rate [relative risk (RR)=0.44, 95%confidence interval (CI):(0.27, 0.69), P=0.000 4] and intraoperative blood loss [weighted mean difference (WMD)=-172.40, 95%CI:(-246.26,-98.53), P<0.000 01] had statistical y significant differences between computer-assisted navigation technique group and conservative insertion group. However, operative time consumption [WMD=-31.45, 95%CI:(-85.56, 22.66), P=0.25] and incidence of complications [RR=0.41, 95%CI:(0.12, 1.41), P=0.16] did not show significant differences between groups. Application of computer-assisted navigation technique in lumbar pedicle screw fixation would improve insertion accuracy. However, further study is stil needed to make clear whether this technique can improve final outcome in post-operative patients.

Objective To investigate the correlation between I405 single nucleotide polymorphism in CETP gene and the therapeutic effect of simvastatin in dyslipidemia patients.Methods Genotype information of I405V in CETP gene was detected by SNaPshot TM primer extension assay in 375 dyslipidemia patients.Blood lipid profiles before and 6 weeks after treatment with simvastatin were recorded to analyze the correlation between the therapeutic effect of simvastatin and I405 polymorphism genostype.Results The frequency of I405 V polymorphism was 38.9%in II genotype,48.5% in IV genotype and 12.5%in VV genotype.After being treated with simvastatin for 6 weeks,the serum levels of TC were significantly decreased by 1.21 mmol/L(P <0.01)and HDL-C level was significantly increased by 0.74 mmol/L(P <0.01).Compared with the IV and VV genotypes of I405V polymorphism,the decrease of TC in II genotype patients were 0.26 mmol/L and 0.16 mmol/L more respectively (P<0.01).Meanwhile,the increase of HDL-C was significantly different among three genotypes(P<0.01).HDL-C in II genotype was increased by 0.85 mmol/L,which was 0.19 mmol/L and 0.15 mmol/L more compared with IV genotype and VV genotype,respectively.Conclusion I405V polymorphism in CETP gene is similar with the lipid-regulating effect of simvastatin.The decrease of blood lipid is more significant in patients with II genotype compared with patients with V allele,suggesting that II genotype is the maker which may predict the therapeutic effect of simvastatin in dyslipidemia patients.However,this conclusion still needs further evaluation.

BACKGROUND:At present, the clinical application of intramedul ary nail in the treatment of tibial shaft fractures has achieved good results. However reamed and unreamed intramedul ary nail in repair of tibial fractures in adults remains controversial. OBJECTIVE:To evaluate clinical efficacy and safety of reamed versus unreamed intramedul ary nailing for the treatment of tibial fractures in adults. METHODS:The literature related to application of reamed or unreamed intramedul ary nailing for tibial fractures published from 1980 to 2015 were searched from Springer, PubMed, and Wanfang database. Related Chinese and English journals of orthopedics were hand-searched. Al randomized control ed trials were col ected. RevMan5.0 provided by Cochrane was used to analyze the data. RESULTS AND CONCLUSION:Seven randomized control ed trials were included according to inclusion criteria, including 1 331 patients. There were 682 cases in the reamed intramedul ary nailing group and 649 cases in the unreamed intramedul ary nailing group. Meta-analysis results showed that compared with the reamed intramedul ary nailing group, implant failure rate was significantly higher in the unreamed intramedul ary nailing group [MD=0.37, 95%CI (0.24, 0.57), P<0.000 01], and nonunion rate was significantly higher [MD=0.54, 95%CI (0.31, 0.93), P=0.03]. There was no significant difference in the incidence of compartment syndrome, the rate of malunion and postoperative infection rate. Results suggested that no difference in the incidence of compartment syndrome, the rate of malunion and postoperative infection rate was found in reamed and unreamed intramedul ary nailing in the repair of adult tibial fractures. Reamed intramedul ary nailing has advantages of low implant failure rate and nonunion rate.

Objective To evaluate the effect of intravitreal injection of triamcinolone for diffuse diabetic macular edema with optical coherence tomography (OCT). Methods 24 patients (25 eyes) with diffuse diabetic macular edema that failed to respond to previous treatment with of laser photocoagulation received an intravitreal injection of 4mg/0.1ml triamcinolone to each eye. The visual acuity, founds fluorescein angiography (FFA), and measurement of the macular retinal thickness with OCT were examined before and after the therapy. Mean follow-up time was 4.6 months (range 3-6 months ). Results Mean best-corrected visual acuity was improved from 0.12?0.07 to 0.30?0.16, the visual acuity improvement was statistically significant(P

BACKGROUND:Stromal cel derived factor-1 (SDF-1)/chemokine receptor 4 (CXCR-4) biological axis plays a chemotactic role in a variety of cel s, making it possible to regulate the regeneration of a variety of tissues. Whether the bidogical is involved in bone morphogenetic protein-2 (BMP-2)-induced homing of bone marrow mesenchymal stem cel s, however, is stil unclear.
OBJECTIVE:To study the role of SDF-1/CXCR4 signaling pathway in BMP-2-induced migration of mouse bone marrow mesenchymal stem cel s.
METHODS:Bone marrow mesenchymal stem cel s in logarithmic growth were selected and intervened with SDF-1 (0, 50, 100 and 200μg/L), BMP-2 (0, 50, 100 and 200μg/L) and AMD3100 (50μg/L) to induce cel migration detected by Transwel method.
RESULTS AND CONCLUSION:The migration of bone marrow mesenchymal stem cel s was closely related to SDF-1 and BMP-2, and proportional to the concentration of both SDF-1 and BMP-2. When SDF-1 and BMP-2 were used jointly, the number of migrated cel s was increased significantly, and highest number of migrated cel s was obtained at 200μg/L. Moreover, these migrated cel s showed a nest-like distribution under microscopy. AMD3100 as an inhibitor markedly suppressed the migration of bone marrow mesencnymal stem cel s induced by BMP-2, but the number of migrated cel s was likely to increase with the increasing concentration of BMP-2 that exceeded a specific value. Overal , our findings show that SDF-1/CXCR4 signaling pathway is an important pathway in BMP-2-induced migration of bone marrow mesenchymal stem cel s.

STATEMENT OF PROBLEM: Titanium-Nickel alloy might be used in various prosthetic restorations since it has a unique property such as super-elasticity and high fatigue resistance. However, little is known about the casting ability of this alloy. PURPOSE: This in vitro study compared the casting accuracy and the porosity made with different investments and various sprue designs to ascertain what casting condition would be better for the fabrication of Ti-Ni cast restorations. MATERIAL AND METHODS: A total of 70 Ti-Ni alloy crowns were made and divided into 7 groups of 10 copings on a metal master die. For measuring the effect of the sprue numbers, two groups with one and two 8-gauge sprues were compared. Moreover, the results of the conventional sprue and the double thickness sprues were compared. Three investments were used; carbon free phosphate bonded investment, titanium investment and gypsum bonded investment. The cast restorations were evaluated at 48 points on the entire circumferential margin with a stereomicroscope measuring in micrometers. Each crown was radiographically examined for casting defects and porosity. Data on casting accuracy were analyzed using two-way and Post hoc Scheffe's comparison to determine whether significant differences existed at the 95% confidence level. Student-Newman-Keuls test were performed to identify significant differences in the number of voids. RESULTS: The double sprueing group and double thickness group had significantly less marginal discrepancy than the single sprueing group (P<.05 and P<.01, respectively). The castings with phosphate bonded investment showed the least marginal discrepancy and the smoothest surface. The castings invested in the gypsum bonded investment had the greatest gaps in margin and the largest failure rate. The double sprueing group and phosphate bonded investment group had significantly smaller void numbers and smaller void size than the other groups. CONCLUSION: Within the limitations of this in vitro study, the casting accuracy of the groups using thicker, double sprue design and the phosphate bonded investment was significantly superior. Moreover, void number and size were less than other groups.
Alloys ; Calcium Sulfate ; Carbon ; Celiac Disease ; Crowns ; Fatigue ; Investments ; Porosity* ; Titanium

BACKGROUND:At present, it remains controversial whether open reduction plate fixation is needed for distal radius fracture in the elderly to restore anatomic reduction of imaging.
OBJECTIVE:To systematical y evaluate the curative effects of operative and nonoperative treatments for distal radius fractures in the elderly.
METHODS:We retrieved PubMed, Springer and Wanfang database using computer. Relevant English and Chinese journals of orthopedics were retrieved by hand. Al literatures on curative effects of operative and nonoperative treatments for distal radius fractures in the elderly were col ected. RevMan 5.0 software provided by Cochrane was used to statistical y analyze the data.
RESULTS AND CONCLUSION:Six literatures were included, including two of randomized control ed study and four of retrospective cohort study. Meta-analysis results displayed that there were no significant differences in both groups in range of motion of wrist joint extension [mean difference (MD)=-0.87, 95%confidence interval (CI) (-3.31, 1.58), P=0.49], range of motion of wrist joint flexion [MD=-2.79, 95%CI(-6.47, 0.88), P=0.14], range of motion of wrist pronation [MD=-0.08, 95%CI(-1.49, 1.64), P=0.92], range of motion of supination [MD=-0.7, 95%CI(-3.52, 2.12), P=0.63] and the occurrence of complication [MD=1.35, 95%CI(0.71, 2.56), P=0.36]. The length of radius in the surgery group was similar to that of normal [MD=2.46, 95%CI(1.78, 3.15), P<0.01]. Ulnar inclination [MD=3.73, 95%CI(2.97, 4.48), P<0.000 01] and palmar tilt angle [MD=6.81, 95%CI(3.72, 9.90), P<0. 000 1] in the surgery group were close to that of normal. There are no significant differences in extension, flexion, pronation and supination activities of wrist and posttreatment complication between two groups. Operative treatment result is superior to that of nonoperative treatment in anatomic reduction.

Knee osteoarthritis (KOA) is a commonly encountered degenerative disease in clinic which gets widespread attention due to its high incidence and disability. The biomechanics is a relatively cause of KOA. This paper reviewed the biomechanics from the aspects of articular stability, adduct torque, gait and alignment.