Yingchuan Zhao

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.

The effect of differing spinal fusion instrumentation on the occurrence of postoperative crankshaft phenomenon in adolescent idiopathic scoliosis.

Study Design Retrospective. Objective To compare the occurrence of the crankshaft phenomenon in patients with adolescent idiopathic scoliosis (AIS) who underwent hybrid, consecutive pedicle screw or interval pedicle screw instrumentation for posterior spinal fusion. Summary of Background Data Scoliosis may progress after posterior spinal fusion in skeletally immature patients with AIS. The crankshaft phenomenon occurs when the anterior column continues to grow in the face of posterior fusion causing characteristic twisting of the fused segment. The optimal surgical method for preventing the occurrence of this complication has not been determined. Methods Sixty seven patients with AIS who underwent posterior fusion over a 6-year period were divided into groups according to fixation method: hybrid instrumentation, interval pedicle screw placement, or consecutive pedicle screw placement. Preoperative, postoperative, and follow-up radiographic measures, including Cobb angle, apical vertebral rotation (AVR), apical vertebral transposition (AVT), rib vertebral angle difference (RVAD) and trunk shift (TS) were assessed. The occurrence of the crankshaft phenomenon was determined. Results The mean follow-up duration was 36 months. There were no between- the-group differences in demographics or preoperative or immediate postoperative measures. At the last follow-up, significant differences among the groups were apparent for Cobb angle, AVR, AVT, RVAD, and TS (all P<0.05). Cobb angle, AVR, AVT, RVAD, and TS significantly increased between the postsurgery and the last follow-up in the hybrid instrumentation group (all P<0.0167). Only TS increased significantly in the 2 other groups. There were 7 cases of crankshaft phenomenon occurrence in the hybrid instrumentation group (33%), but none in the other 2 groups. Conclusions These findings suggest that in skeletally immature patients with AIS, hybrid instrumentation cannot effectively prevent occurrence of the crankshaft phenomenon, whereas interval and consecutive pedicle screw instrumentation may be more (and equally) efficacious in this regard.

Adapted Simplified Chinese (Mainland) Version of Scoliosis Research Society-22 Questionnaire

Study Design. Validation study to define validity and reliability of an adapted and translated questionnaire. Objective. This study attempted to validate the traditional Chinese (Hong Kong) version of the modified Scoliosis Research Society (SRS) Outcomes Instrument, SRS-22, into simplified Chinese for use in mainland China. Summary of Background Data. Although a traditional Chinese (Hong Kong) adaptation of the SRS-22 has been previously validated, no culturally adapted, validated SRS-22 exists for use in mainland China. Methods. Adhering to International Quality of Life Assessment Project guidelines, the adapted traditional Chinese SRS-22 was translated into simplified Chinese while referencing the original English questionnaire. To examine the psychometric properties and clinical application of the adapted simplified Chinese SRS-22, a survey was conducted in a group of randomly selected 87 patients previously surgically treated at an outpatient clinic. Reliability assessment of the simplified Chinese version of the SRS-22 was determined by calculating Cronbach’s α and intraclass coefficient (ICC) values. Concurrent validity was evaluated by comparing SRS-22 domains with relevant domains of the simplified Short-Form-36 questionnaire; correlation was made using Pearson correlation coefficients. Results. Cronbach’s &agr;, applied to each of the 22 questions of the adapted SRS-22, revealed very satisfactory internal consistency (Cronbach’s &agr; = 0.80–0.89) for function/activity and pain, and good consistency (Cronbach’s &agr; = 0.50–0.79) for the remaining domains. The test/retest reproducibility was found to be good (ICC ≥0.40–0.75) in the function/activity domain, and excellent (ICC ≥0.75) in the remaining domains. In terms of concurrent validity, 3 domains had excellent correlation, while 10 had good correlation, and 21 had moderate correlation. Discussion. The authors report the validation of a simplified Chinese SRS-22 for use in mainland China, which is culturally relevant, reliable, repeatable, psychometrically sound, and suitable for immediate clinical use.

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.

Associations between Body Mass and the Outcome of Surgery for Scoliosis in Chinese Adults

Background In this study we intended to prove that being overweight has an unfavorable impact on the surgical treatment outcome of adult idiopathic scoliosis (AdIS). Methods This is a retrospective study on the surgical treatment of seventy-one more than 30 years old (58 females and 13 males; mean age 42.9±12.2) idiopathic scoliotic patients with a minimum follow up of at least 2 years. The patients were divided into an overweight group (BMI≥23) and a non-overweight group (BMI<23). Preoperative, postoperative first erect and final follow-up radiographic measures, perioperative data, the Oswestry disability index (ODI), and the visual analog scale (VAS) were reviewed and compared. Findings In the overweight group, no significant differences in radiographic measures, perioperative data, preoperative comorbidities, or postoperative complications, except for the more frequent concomitance of preoperative thoracic kyphosis 37.9±7.7 vs. 26.5±11.8 (P = 0.000) and thoracolumbar kyphosis 14.9±10.1 overweighted group vs. 6.5±9.9 non-overweighted group respectively (P = 0.002) were found. A higher morbidity of hypertension 36.8% vs. 9.6% (P = 0.004) was also observed in the overweight group. Postoperative ODI and VAS improved significantly in both groups compared to pre-operative values. The postoperative ODI of the overweight group (19.6±12.4) was significantly higher than that of the non-overweight group (12.4±7.9) (P = 0.022). Conclusions Overweight adult idiopathic scoliotic patients had more frequent concomitance of preoperative thoracic kyphosis and thoracolumbar kyphosis and more serious postoperative pain. However, BMI did not affect the outcomes of surgical correction for coronal and sagittal scoliotic deformity and their postoperative complication rates were not significantly affected.

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.

Prediction of postoperative trunk imbalance after posterior spinal fusion with pedicle screw fixation for adolescent idiopathic scoliosis.

The objective of this retrospective study was to explore, which radiographic parameters, immediately after posterior spinal fusion with pedicle screw fixation for adolescent idiopathic scoliosis (AIS), best correlate with subjacent disc wedging at a minimum of 2-year follow-up. Sixty-four consecutive AIS patients who underwent posterior pedicle screw-only instrumentation were studied. Preoperative and postoperative radiographs were obtained to measure various parameters regarding global coronal, shoulder, sagittal, and regional balance. Specific correlation of these parameters to selected 2-year postoperative disc wedging and lowest-instrumented vertebra (LIV) tilt and translation were analyzed. The average lateral disc opening changed from 4.59±4.75 preoperatively to 1.46±2.82 at 2 weeks and 2.81±6.43 at 2 years postoperatively. Two-year postoperative lateral disc opening significantly correlated with the 2-week postoperative lateral disc opening, C7 plumbline relative to the posterior–superior corner of the first sacral vertebra distance, and LIV-center sacral vertical line (CSVL) distance (r2=0.7433, P<0.0001). The two-year postoperative LIV tilt significantly correlated with the 2-week postoperative LIV tilt, T12-LIV lordosis, LIV-CSVL distance, and C7-CSVL distance (r2=0.8879, P<0.0001). Two-year postoperative LIV-CSVL significantly correlated with 2-week postoperative LIV-CSVL distance and lateral disc opening (r2=0.6104, P<0.0001). Two-year postoperative disc wedging, LIV tilt, and LIV translation occurred most often when disc wedging and LIV deviation or obliquity existed immediately postoperatively. This study identified a potential indicator for AIS repair. Preoperative surgical planning and intraoperative correction are important for avoiding subjacent regional imbalance after scoliosis fusion.

Screening of diagnostic markers for osteosarcoma

Osteosarcoma, which is the most common type of highly malignant bone tumor in children and adolescents, has poor diagnosis and 2-year survival rates of 15-20% following surgery or radiotherapy, and has therefore generated marked attention. In order to investigate the potential biomarkers for diagnosing osteosarcoma, the expression profiling data from normal and disease tissues were compared, respectively, and the differentially‑expressed genes were analyzed by three different statistical tests. Interacting proteins were determined and an interaction network was constructed by Search Tool for the Retrieval of Interacting Genes database. Subsequently, the protein interaction network was decomposed and Gene Otology annotation using Cytoscape, Mcode and Bingo, was conducted on the function modules. Finally, three differentially‑expressed genes GJA1, COL1A2 and COL5A2 were identified, and an interaction network was successfully generated with COL1A2 and COL5A2 at the core. From the results, it was observed that COL1A2 and COL5A2 interact with a number of genes of the matrix metalloprotease (MMP) family, including MMP1, MMP2, MMP3 and MMP14, TGFβ and RUNX2. Furthermore, these genes have been confirmed to be important in the tumorigenesis of osteosarcoma. It was hypothesized that the upregulation of the COL gene family may be considered as a diagnostic marker for osteosarcoma and collagen may be administered as a therapy.

Validation of the simplified chinese version of the functional rating index for patients with low back pain.

Study Design. Cross-cultural translation and psychometric testing of the Functional Rating Index (FRI). Objective. To evaluate the reliability and validity of the adapted simplified Chinese FRI (SC-FRI) for patients with low back pain (LBP). Summary of Background Data. The FRI is a reliable and valid instrument to assess the perception of function and pain for patients with LBP. However, there is no culturally adapted, reliable, and validated FRI for use in mainland China. Methods. The translation and cross-cultural adaptation were performed following international guidelines. The SC-FRI was administered to 115 patients with LBP along with the simplified Chinese version of the Oswestry Disability Index, 36-Item Short Form Health Survey, and the visual analogue scale. Psychometric testing included internal consistency, test-test reliability, concurrent criterion validity, and construct validity. Results. A high completion rate of 96% and no floor or ceiling effects were noted for the SC-FRI. The internal consistency was good (i.e., Cronbach &agr; = 0.897 for the overall SC-FRI; range, 0.851–0.890, if an item was deleted). Test-retest reliability was excellent, with an intraclass correlation coefficient of 0.948 (95% confidence interval, 0.917–0.968). Concurrent criterion validity assessment demonstrated that the SC-FRI significantly correlated with the visual analogue scale (r = 0.852, P < 0.0001) and the simplified Chinese version of the Oswestry Disability Index (r = 0.958, P < 0.0001). Construct validity was confirmed by the significant Pearson correlation between the SC-FRI and Physical Functioning (r = −0.802, P < 0.0001), Bodily Pain (r = −0.698, P < 0.0001), Social Functioning (r = −0.573, P < 0.0001), Role-Physical (r = −0.503, P < 0.0001), and General Health (r = −0.502, P < 0.0001) domains of the 36-Item Short Form Health Survey. Conclusion. The SC-FRI showed excellent reliability and validity in the evaluation of pain and the functional health status of Chinese-speaking patients with LBP. It is simple and easy to use and can be recommended in clinical and research practice in mainland China.