Haijian Ni

Application of 3D rapid prototyping technology in posterior corrective surgery for Lenke 1 adolescent idiopathic scoliosis patients.

Abstract A retrospective study to evaluate the effectiveness of 3-dimensional rapid prototyping (3DRP) technology in corrective surgery for Lenke 1 adolescent idiopathic scoliosis (AIS) patients. 3DRP technology has been widely used in medical field; however, no study has been performed on the effectiveness of 3DRP technology in corrective surgery for Lenke 1 AIS patients. Lenke 1 AIS patients who were preparing to undergo posterior corrective surgery from a single center between January 2010 and January 2012 were included in this analysis. Patients were divided into 2 groups. In group A, 3-dimensional (3D) printing technology was used to create subject-specific spine models in the preoperative planning process. Group B underwent posterior corrective surgery as usual (by free hand without image guidance). Perioperative and postoperative clinical outcomes were compared between 2 groups, including operation time, perioperative blood loss, transfusion volume, postoperative hemoglobin (Hb), postoperative complications, and length of hospital stay. Radiological outcomes were also compared, including the assessment of screw placement, postoperative Cobb angle, coronal balance, sagittal vertical axis, thoracic kyphosis, and lumbar lordosis. Subgroup was also performed according to the preoperative Cobb angle: mean Cobb angle <50° and mean Cobb angle >50°. Besides, economic evaluation was also compared between 2 groups. A total of 126 patients were included in this study (group A, 50 and group B, 76). Group A had significantly shorter operation time, significantly less blood loss and transfusion volume, and higher postoperative Hb (all, P < 0.001). However, no significant differences were observed in complication rate, length of hospital stay, and postoperative radiological outcomes between 2 groups (all, P>0.05). There was also no significant difference in misplacement of screws in total populations (16.90% vs 18.82%, P = 0.305), whereas a low misplacement rate of pedicle screws was observed in patients whose mean Cobb angle was >50° (9.15% vs 13.03%, P = 0.02). Besides, using 3DRP increased the economic burden of patients (157,000 ± 9948.85 Ren Min Bi (RMB) vs 152,500 ± 11,445.52 RMB, P = 0.03). Using the 3D printing technology before posterior corrective surgery might reduce the operation time, perioperative blood loss, and transfusion volume. There did not appear to be a benefit to using this technology with respect to complication rate and postoperative radiological outcomes; however, 3D technology could reduce the misplacement rate in patients whose preoperative mean Cobb angle was >50°. Besides, it also increased the patients’ hospital cost. Therefore, future prospective studies are needed to elucidate the efficacy of this emerging technology.

Surgical treatment of transverse patella fractures by the cable pin system with a minimally invasive technique.

BACKGROUND: Transverse patella fractures are the most common type of patella fractures. Minimally invasive surgical technique for treatment of transverse patella fractures with the Cable Pin System has not been previously reported. METHODS: Thirty-four patients with displaced transverse fractures of the patella were included in this prospective study and were operatively treated by the Cable Pin System with a minimally invasive technique. Postoperative evaluation was based on radiographs, Visual Analog Scale of pain, range of motion, and Bostman grading scale. RESULTS: A total of 31 patients were finally included, with an average follow-up period of 21 months. The average operation time was 48 minutes. Intraoperative fluoroscopy was used for 2 to 4 times (average: 2.4 times). Radiographic evidence of solid fracture union was observed in all cases in a mean period of 7.2 weeks. The Visual Analog Scale score for pain was 3.3 ± 1.4 and 1.5 ± 1.3 at 4 weeks after surgery and when radiographic fracture healing was achieved, respectively. Twenty-nine patients achieved full knee range of motion, while two patients had 10° loss of full flexion at the final follow-up visit. The average Bostman score was 29.1/30 (range, 27–30) at 1 year after surgery, and an evaluation of “excellent” was observed in 30 patients at the final follow-up visit. CONCLUSION: Surgical treatment of transverse patella fractures by the Cable Pin System with a minimally invasive technique was shown to provide satisfactory clinical results and excellent knee functions, with less pain and low incidence of complications. It could be a new option for treatment of transverse patella fractures. LEVEL OF EVIDENCE: III.

Potential Role of lncRNAs in Contributing to Pathogenesis of Intervertebral Disc Degeneration Based on Microarray Data

Background Our study intended to identify potential long non-coding RNAs (lncRNAs) and genes, and to elucidate the underlying mechanisms of intervertebral disc degeneration (IDD). Material/Methods The microarray of GSE56081 was downloaded from the Gene Expression Omnibus database, including 5 human control nucleus pulposus tissues and 5 degenerative nucleus pulposus tissues, which was on the basis of GPL15314 platform. Identification of differentially expressed lncRNAs and mRNAs were performed between the 2 groups. Then, gene ontology (GO) and pathway enrichment analyses were performed to analyze the biological functions and pathways for the differentially expressed mRNAs. Simultaneously, lncRNA-mRNA weighted coexpression network was constructed using the WGCNA package, followed by GO and KEGG pathway enrichment analyses for the genes in the modules. Finally, the protein-protein interaction (PPI) network was visualized. Results A total of 135 significantly up- and 170 down-regulated lncRNAs and 2133 significantly up- and 1098 down-regulated mRNAs were identified. Additionally, UBA52 (ubiquitin A-52 residue ribosomal protein fusion product 1), with the highest connectivity degree in PPI network, was remarkably enriched in the pathway of metabolism of proteins. Eight lncRNAs – LINC00917, CTD-2246P4.1, CTC-523E23.5, RP4-639J15.1, RP11-363G2.4, AC005082.12, MIR132, and RP11-38F22.1 – were observed in the modules of lncRNA-mRNA weighted coexpression network. Moreover, SPHK1 in the green-yellow module was significantly enriched in positive regulation of cell migration. Conclusions LncRNAs LINC00917, CTD-2246P4.1, CTC-523E23.5, RP4-639J15.1, RP11-363G2.4, AC005082.12, MIR132, and RP11-38F22.1 were differentially expressed and might play important roles in the development of IDD. Key genes, such as UBA52 and SPHK1, may be pivotal biomarkers for IDD.

Using side-bending radiographs to determine the distal fusion level in patients with single thoracic idiopathic scoliosis undergoing posterior correction with pedicle screws.

Study Design Prospective. Objectives To evaluate a strategy to determine the distal fusion level in posterior pedicle screw correction of single thoracic idiopathic scoliosis. Summary of Background Data No standard method for selecting the lowest instrumented vertebra (LIV) for the correction of thoracic adolescent idiopathic scoliosis with posterior all-pedicle screw instrumentations exists. Methods Thirty-eight patients with single right thoracic (Lenke 1A) adolescent idiopathic scoliosis undergoing posterior pedicle screw fixation were studied. The LIV was determined using guidelines based on preoperative side-bending radiographs. In brief, (1) the whole thoracic Cobb curve should be included in the fusion mass, and the LIV should not be superior to the lower-end vertebra of the Cobb measurement. (2) On the right side-bending radiographs, the LIV should be derotated to neutral in skeletally immature (Risser 0 to 3) patients and the disc immediately below the LIV must open on the left side by at least 5 degrees. (3) On the left side-bending radiographs, the disc immediately below the LIV must be open on the right side by at least 0 degree. The first segment meeting the criteria when proceeding from the lower-end vertebra caudally is chosen as the LIV. Outcomes were based on the standing radiographs. Results Minimum follow-up was 2 years. The mean preoperative thoracic curve was 48.4±9.2 degrees and 12.6±6.1 degrees at final follow-up, resulting in a mean correction of 74.7%±8.5%. The mean preoperative compensatory lumbar curve of 23.7±7.5 degrees was 6.3±4.8 degrees at final follow-up. A change in lumbar lordosis from −41.2±11.9 degrees preoperatively to −38.2±9.9 degrees at final follow-up occurred. All patients achieved coronal balance and no decompensation or adding-on phenomenon was observed. Compared with the recommended fusion end by the Harrington stable zone method, 86.9% patients were saved 1 or more motion segment. Conclusions The method described was effective in obtaining satisfactory curve correction, adequate trunk balance, and preservation of motion segments.

Radiographic Parameters in Adult Degenerative Scoliosis and Different Parameters Between Sagittal Balanced and Imbalanced ADS Patients.

Abstract A retrospective study. To summarize and describe the radiographic parameters of adult degenerative scoliosis (ADS) and explore the radiological parameters which are significantly different in sagittal balanced and imbalanced ADS patients. ADS is the most common type of adult spinal deformity. However, no comprehensive description of radiographic parameters in ADS patients has been made, and few studies have been performed to explore which radiological parameters are significantly different between sagittal balanced and imbalanced ADS patients. Medical records of ADS patients in our outpatient clinic from January 2012 to January 2014 were reviewed. Demographic data including age and sex, and radiographic data including the coronal Cobb angle, location of apical vertebra/disc, convexity of the curve, degree of apical vertebra rotation, curve segments, thoracic kyphosis (TK), lumbar lordosis (LL), thoracolumbar kyphosis (TL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), sagittal vertical axis (SVA), and PI minus LL (PI − LL) were reviewed to make comprehensive description of radiographic parameters of ADS. Furthermore, patients were divided into 2 groups according to whether the patients’ sagittal plane was balanced: Group A (imbalanced, SVA > 5 cm) and Group B (balanced, SVA ⩽ 5 cm). Demographic and radiological parameters were compared between these 2 groups. A total of 99 patients were included in this study (Group A = 33 and Group B = 66; female = 83 and male = 16; sex ratio = 5:1). The median of age were 67 years (range: 41–92 years). The median of coronal Cobb angle and length of curve was 23 (range: 10–75°) and 5 segments (range: 3–7), respectively. The most common location of apical vertebra was at L2 to L3 (81%) and the median of degree of apical vertebra rotation was 2° (range: 1–3). Our study also showed significant correlations between coronal Cobb angle and curve segments (r = 0.23, P < 0.005) and degree of apical vertebra rotation (r = 0.53, P < 0.005). With regard to the sagittal balance, there were significant differences in age, LL, PT, coronal Cobb angle, degree of apical vertebra rotation, and PI − LL between imbalanced group and balanced group (all P < 0.05); however, no significant difference was observed in gender, TK, TL, SS, and PI. Our study provided the general radiographic parameters of ADS. Weak or moderate but significant correlations between coronal Cobb angle and curve segments and degree of apical vertebra rotation were observed. Furthermore, age, coronal Cobb angle, LL, PT, and PI − LL were significantly different between sagittal balanced and imbalanced ADS patients.

Long-term outcomes of one-stage anterior debridement, bone grafting, and internal fixation for the treatment of lower cervical tuberculosis with kyphosis

Abstract Background. Patients with spinal deformities and nerve compression due to spinal tuberculosis often require surgical intervention. The objective of this study was to assess the long-term therapeutic effectiveness of one-stage anterior debridement, bone grafting, and internal fixation for lower cervical tuberculosis with kyphosis. Methods. Twenty-one patients with lower cervical tuberculosis and cervical kyphosis received one-stage anterior debridement, autologous iliac bone grafting, and internal plate fixation. Patients were followed-up postoperatively for at least 5 years. Outcome measures included neck pain using Visual Analogue Scale (VAS) scores, Frankel classification of spinal cord injury, and Cobb angle of cervical kyphosis. Results. Eighteen patients had lesions in 2 vertebrae and 3 had lesions in 3 vertebrae. Cervical tuberculosis was cured in all patients. The mean preoperative VAS score for neck pain was 8 (range: 6–10), whereas the mean best postoperative VAS score was 0.6 (range: 0–3). Mean final VAS score was significantly higher than the best VAS score (2.14 vs. 0.62). Of the 13 patients with symptoms of spinal cord compression, 9 improved by 1 grade and 4 improved by 2 grades according to Frankel classification at final follow-up. The mean preoperative Cobb angle of cervical kyphosis was 29° (range: 15°–50°), whereas the mean postoperative Cobb angle at final follow-up was −1.8° (range: 2–7°). Conclusions. One-stage anterior debridement, bone grafting, and internal fixation can effectively remove lesions, decompress the nerve, reduce pain, and correct kyphosis in patients with cervical tuberculosis and associated kyphosis. Long-term postoperative outcomes were satisfactory.

An increased kyphosis of the thoracolumbar junction is correlated to more axial vertebral rotation in thoracolumbar/lumbar adolescent idiopathic scoliosis.

Study Design. A retrospective correlation study. Objective. To identify radiographically if there is a correlation of the sagittal thoracolumbar alignment to the axial vertebral rotation and coronal scoliotic curvature in thoracolumbar/lumbar (TL/L) adolescent idiopathic scoliosis (AIS). Summary of Background Data. The consistent positive correlation between coronal angulations and axial rotation has been defined as a typical feature of AIS. However, the correlation of sagittal alignment transformation to axial and/or coronal deformity has not been definitely described, especially for primary TL/L AIS. Methods. On standard anteroposterior and lateral radiographs of 43 patients with TL/L AIS, coronal and sagittal parameters including primary TL/L and compensatory thoracic curve, thoracic kyphosis, thoracolumbar junctional sagittal curve (TLJS), and lumbar lordosis, were evaluated using the Cobb method. Apical vertebral rotation (AVR) was evaluated using the Perdriolle torsionmeter. The correlation was investigated between all parameters. After the patients were divided into 2 subgroups according to the TLJS curvature, the average AVR and coronal TL/L Cobb were compared between the 2 groups. Results. The average TLJS Cobb was 4.5° ± 8.8° (range, −12.5°–24.3°) with 28 cases (65.1% of all cases) in TLJS+ (kyphosis) group and 15 cases in TLJS− (lordosis) group. Significant correlations were observed between AVR and coronal TL/L curvature (P < 0.001), and between AVR and sagittal TLJS Cobb angle (P < 0.001). These correlations still existed when the partial correlation analysis was conducted. The correlation between sagittal TLJS and coronal TL/L curvature became nonsignificant (P = 0.405) when the partial correlation analysis was conducted with AVR as control variable. Besides, a significant difference of 7.0° was observed in average AVR between TLJS+ and TLJS− subgroups (P < 0.001). Conclusion. From the standard anteroposterior and lateral radiographs, an increased kyphosis of the thoracolumbar junction was observed in TL/L AIS, and it was demonstrated to be positively correlated to more axial vertebral rotation of the scoliotic spine.

The Relationship between T1 Sagittal Angle and Sagittal Balance: A Retrospective Study of 119 Healthy Volunteers.

T1 sagittal angle has been reported to be used as a parameter for assessing sagittal balance and cervical lordosis. However, no study has been performed to explore the relationship between T1 sagittal angle and sagittal balance, and whether T1 sagittal angle could be used for osteotomy guidelines remains unknown. The aim of our study is to explore the relationship between T1 sagittal angle and sagittal balance, determine the predictors for T1 sagittal angle, and determine whether T1 sagittal angle could be used for osteotomy guidelines to restore sagittal balance. Medical records of healthy volunteers in our outpatient clinic from January 2014 to August 2015 were reviewed, and their standing full-spine lateral radiographs were evaluated. Demographic and radiological parameters were collected and analyzed, including age, gender, T1 sagittal angle, maxTK, maxLL, SS, PT, and PI. Correlation coefficients between T1 sagittal angle and other spinopelvic parameters were determined. In addition, multiple regression analysis was performed to establish predictive radiographic parameters for T1 sagittal angle as the primary contributors. A total of 119 healthy volunteers were recruited in our study with a mean age of 34.7 years. It was found that T1 sagittal angle was correlated with maxTK with very good significance (r = 0.697, P<0.001), maxLL with weak significance (r = 0.206, P = 0.024), SS with weak significance (r = 0.237, P = 0.009), PI with very weak significance (r = 0.189, P = 0.039), SVA with moderate significance (r = 0.445, P<0.001), TPA with weak significance (r = 0.207, P = 0.023), and T1SPI with weak significance (r = 0.309, P = 0.001). The result of multiple regression analysis showed that T1 sagittal angle could be predicted by using the following regression equation: T1 sagittal angle = 0.6 * maxTK—0.2 * maxLL + 8. In the healthy population, T1 sagittal angle could be considered as a useful parameter for sagittal balance; however, it could not be thoroughly replaced for SVA. maxTK was the primary contributor to T1 sagittal angle. According to this equation, we could restore sagittal balance by surgically changing thoracic kyphosis and lumbar lordosis, which could serve as a guideline for osteotomy.

Could CCI or FBCI Fully Eliminate the Impact of Curve Flexibility When Evaluating the Surgery Outcome for Thoracic Curve Idiopathic Scoliosis Patient? A Retrospective Study.

Purpose To clarify if CCI or FBCI could fully eliminate the influence of curve flexibility on the coronal correction rate. Methods We reviewed medical record of all thoracic curve AIS cases undergoing posterior spinal fusion with all pedicle screw systems from June 2011 to July 2013. Radiographical data was collected and calculated. Student t test, Pearson correlation analysis and linear regression analysis were used to analyze the data. Results 60 were included in this study. The mean age was 14.7y (10-18y) with 10 males (17%) and 50 females (83%). The average Risser sign was 2.7. The mean thoracic Cobb angle before operation was 51.9°. The mean bending Cobb angle was 27.6° and the mean fulcrum bending Cobb angle was 17.4°. The mean Cobb angle at 2 week after surgery was 16.3°. The Pearson correlation coefficient r between CCI and BFR was -0.856(P<0.001), and between FBCI and FFR was -0.728 (P<0.001). A modified FBCI (M-FBCI) = (CR-0.513)/BFR or a modified CCI (M-CCI) = (CR-0.279)/FFR was generated by curve estimation has no significant correlation with FFR (r=-0.08, p=0.950) or with BFR (r=0.123, p=0.349). Conclusions Fulcrum-bending radiographs may better predict the outcome of AIS coronal correction than bending radiographs in thoracic curveAIS patients. Neither CCI nor FBCI can fully eliminate the impact of curve flexibility on the outcome of correction. A modified CCI or FBCI can better evaluating the corrective effects of different surgical techniques or instruments.

Role of T1 Pelvic Angle in Assessing Sagittal Balance in Outpatients With Unspecific Low Back Pain.

AbstractThe aim of the study was to explore the significance of T1 pelvic angle (TPA) for assessment of sagittal balance in a cohort of Chinese patients with unspecific low back pain.TPA has been commonly used to assess sagittal balance in adult spinal deformity. However, whether TPA could be used to assess sagittal balance in patients with unspecific low back pain effectively remains unanswered.Medical records of outpatients with unspecific low back pain who received treatment in our outpatient clinic between September 2013 and November 2014 were reviewed. Demographic data and radiographic data were collected. Correlation coefficients between TPA and other sagittal parameters were analyzed, and the intraclass correlation coefficient (ICC) analysis was performed to assess the inter- and intra-observer reliability of TPA. Patients were divided into 2 groups according to whether they were well-aligned (TPA ⩽ 20°) or poorly aligned (TPA > 20°), and then demographic and sagittal parameters were compared between the 2 groups of patients.A total of 97 patients with unspecific low back pain were included in this study. The inter- and intraobserver reliability of the TPA measure had excellent agreement (ICC = 0.985 and 0.919, respectively). There were significant correlations between TPA and age, LL, PT, PI, T1SPI, SVA, and NRS (all P < 0.05). Of the 38 well-aligned patients in Group A, SVA was ⩽5 cm in 33 (86.84%) patients and >5 cm in the other 5 (13.16%) patients, and of the 59 poorly aligned patients in Group B, SVA was >5 cm in 42 (71.19%) patients and ⩽5 cm in the other 17 (28.81%) patients. There were significant differences in age, LL, SS, PT, PI, T1SPI, SVA, and NRS between the 2 groups of patients, but no significant difference was observed in TK and TL.TPA could be used to assess sagittal balance in outpatients with unspecific low back pain effectively.