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.

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 open reduction and multi-dimensional several pin fixation of Gartland type Ⅲ supracondylar fractures with late callus formation in children.Methods The study involved 37 children of Gartland type m supracondylar fractures with late callus formation undergone posteromedial elbow incision,open reduction via bilateral triceps sparing approach,several K-wire internal fixation and early functional rehabilitation from May 2009 to May 2011.There were 23 males and 14 females at 3-13 years of age (mean,7 years).Postoperative results were evaluated according to Flynn standard.Mean 9.5 months of follow-up was made.Results The results were excellent in 28 cases,good in five,fair in two and poor in two.No serious complications occurred after operation.Conclusion Open reduction and multi-dimensional several K-wire fixation is an effective treatment for Gartland type Ⅲ supracondylar fractures with late callus formation in children and hence provides a choice for clinical use.

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.

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.

BACKGROUND:Dysphagia is one of common early complications after anterior cervical fusion. Medium and severe dysphagia often causes serious influence on the patients. A variety of factors have been shown to have a correlation with the postoperative dysphagia, but specific mechanism is stil unclear. OBJECTIVE:To explore the risk factors for dysphagia after single-level anterior cervical fusion. METHODS:From January 2011 to June 2013, data of 44 patients with dysphagia and 213 patients without dysphagia after single-level anterior cervical fusion were compared. The baseline data (age, gender, ethnicity, body mass index, smoking history, drinking history, hypertension, diabetes, course length, and type of cervical spondylosis) and perioperative data (intraoperative blood loss, internal fixation, the location of the operated level, operation time, and the side of operation approach) between two groups were compared by Logistic regression analysis to determine risk factors for postoperative dysphagia.RESULTS AND CONCLUSION:A total of 257 patients were included with a fol ow-up for 6 to 24 months postoperatively and 44 of them suffered from dysphagia after single-level anterior cervical fusion. The overal prevalence for postoperative dysphagia was 17.1%. Univariate analysis indicated that age, gender, the location of the operated level, and course length were associated with postoperative dysphagia. Logistic regression analysis of multivariate analysis demonstrated that independent predictors for postoperative dysphagia included gender (female), age (>60 years), the location of the operated level (C 4-5 , C 5-6 ), and course length (>12 months). Clinicians should give appropriate recognition and take corresponding measures to avoid it.

BACKGROUND:Despite tissue repair with a kind of stem cels has achieved great outcomes, but the combination of two or more kinds of stem cels to construct tissue-engineered bone is stil rare.
OBJECTIVE:To evaluate the efficacy of tissue-engineered bone constructed based on combining adipose-derived stem cels with bone marrow mesenchymal stem cels and alogenic bone in rabbit posterior intertransverse lumbar interbody fusion models.
METHODS:Seventy-five New Zealand rabbits were randomly divided into five groups. L5,6 interbody fusion models were made in each group. Then, these five groups were respectively treated as folows (1) group A: bone marrow mesenchymal stem cels/alograft iliac bone with adipose-derived stem cels; (2) group B: bone marrow mesenchymal stem cels/alograft iliac bone with normal saline; (3) group C: alograft iliac bone with adipose-derived stem cels; (4) group D: alograft iliac bone with normal saline; group E: autologous iliac bone alone. Each group was detected by PET/CT to contrast the standard uptake value at 1, 3, 5 weeks postoperatively.
RESULTS AND CONCLUSION: PET/CT images showed varying degrees of bone fusion and bone metabolism enhancement in the five groups. With time, the standard uptake value was increased in each group, and except the group D, the standard uptake value was higher in al the groups at 3, 5 weeks than at 1 week (P < 0.05). There was no difference in the standard uptake value of al the five groups at weeks 3 and 5 after operation (P > 0.05). The standard uptake value of the group A was better than that in the group B and group E (P < 0.05). Taken together, the combination of adipose-derived stem cels and bone marrow mesenchymal stem cels for rapid production of tissue-engineered bone has good osteogenesis and vascularization.

BACKGROUND: Osteogenic ability of bone morphogenetic protein-2 has been wel documented in many experiments, but a series of factors are involved in osteogenesis induction that is a complex network adjustment process. OBJECTIVE: To quantitatively determine the level of insulin-like growth factor I during the lumbar spinal fusion of rabbits induced by recombinant human bone morphogenetic protein-2. METHODS: Sixty adult male New Zealand white rabbits were randomly divided into three groups: bone autograft, bone al ograft or composite bone (bone al ograft with 75 μg recombinant human bone morphogenetic protein-2) was implanted into the L5-6 intertransverse process of rabbits, respectively. At days 7, 14, 21, 28, 35 after implantation, formed cal us was taken to detect the expression of insulin-like growth factor I using real-time fluorescence quantitative PCR. RESULTS AND CONCLUSION: In the three groups, the expression of insulin-like growth factor I gradual y increased with implantation time, peaked at 28 days and then decreased. At 7 days after implantation, the expression of insulin-like growth factor I was higher in the autograft group than the composite and al ograft groups (P < 0.05); at 14 days, the expression of insulin-like growth factor I was higher in the autograft and composite groups than the al ograft group (P < 0.05); at 21, 28 and 35 days, the expression of insulin-like growth factor I was higher in the composite group than the autograft and al ograft groups (P < 0.05). These findings indicate that recombinant human bone morphogenetic protein-2 can improve the expression of insulin-like growth factor I effectively during the lumbar spinal fusion.

Objective To systematically review the clinical efficacy and complications of in-tramedullary nailing (IMN) versus plating for distal tibia fractures in adults. Methods A comprehensive search was conducted for the randomized controlled trials from January 2005 to October 2016 on the IMN versus plating for distal tibia fractures in The Cochrane Library, Springer, Pubmed, Medline Embase, CNKI, Wanfang Data and manually as well. The quality of the included literature was evaluated accordingly. RevMan5.3 provided by Cochrane was used to analyze the data. Results A total of 7 randomized con-trolled trials (n=514) were included involving 514 participants (IMN: 267; Plating: 247). IMN achieved a significantly lower superficial infection incidence [MD=2.41, 95% CI (1.11, 5.23), P=0.03]. There were no significant differences between IMN and plating in deep infection [MD=1.43, 95% CI (0.51, 4.04), P=0.50], nonunion [MD=1.35, 95% CI (0.56, 2.38), P=0.51], malunion [MD=0.88, 95% CI (0.50, 1.57), P=0.67], delayed union [MD=0.69, 95% CI (0.26, 1.85), P=0.46],or removal of metal work [MD=1.05, 95% CI (0.81, 1.36), P=0.72]. Conclusion Since plating may lead to a significantly higher rate of superficial infection for adult distal tibial fractures than intramedullary nailing, special attention should be paid to aseptic manipulation during plating, and minimally invasive pro-cedures and soft tissue protection measures should be taken as far as possible.