Dajiang Wu

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.

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.

Clinical and radiographic outcomes of the treatment of adolescent idiopathic scoliosis with segmental pedicle screws and combined local autograft and allograft bone for spinal fusion: a retrospective case series

BackgroundHigh morbidity has been reported with iliac crest bone graft harvesting; however, donor bone is typically necessary for posterior spinal fusion. Autograft bone combined with allograft may reduce the morbidity associated with iliac crest bone harvesting and improve the fusion rate. Our aim in this study was to determine the presence of complications, pseudarthrosis, non-union, and infection using combined in situ local autograft bone and freeze-dried cancellous allograft bone in patients undergoing posterior spinal fusion for the treatment of adolescent idiopathic scoliosis.MethodsA combination of in situ local autograft bone and freeze-dried cancellous allograft blocks were used in 50 consecutive patients with adolescent idiopathic scoliosis treated by posterior fusion and Moss Miami pedicle screw instrumentation. Results were assessed clinically and radiographically and quality of life and functional outcome was evaluated by administration of a Chinese version of the SRS-22 survey.ResultsThere were 41 female and 9 male patients included for analysis with an average age of 14.7 years (range, 12-17). All patients had a minimum follow-up of 18 months (range, 18 to 40 months). The average preoperative Cobb angle was 49.8° (range, 40° to 86°). The average number of levels fused was 9.8 (range, 6-15). Patients had a minimum postoperative follow-up of 18 months. At final follow-up, the average Cobb angle correction was 77.8% (range, 43.4 to 92.5%). There was no obvious loss in the correction, and the average loss of correction was 1.1° (range, 0° to 4°). There was no pseudarthrosis and no major complications.ConclusionsIn situ autograft bone combined with allograft bone may be a promising method enhances spinal fusion in AIS treated with pedicle screw placement. By eliminating the need for iliac crest bone harvesting, significant morbidity may be avoided.

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.

Fuzzy Clustering Analysis of Osteosarcoma Related Genes

Osteosarcoma is the most common malignant bone-tumor with a peak manifestation during the second and third decade of life. In order to explore the influence of genetic factors on the mechanism of osteosarcoma by analyzing the inter relationship between osteosarcoma and its related genes, and then provide potential genetic references for the prevention, diagnosis and treatment of osteosarcoma, we collected osteosarcoma related gene sequences in Genebank of National Center for Biotechnology Information (NCBI) and local alignment analysis for a pair of sequences was carried out to identify the measurement association among related sequences. Then fuzzy clustering method was used for clustering analysis so as to contact the unknown genes through the consistent osteosarcoma related genes in one class. From the result of fuzzy clustering analysis, we could classify the osteosarcoma related genes into two groups and deduced that the genes clustered into one group had similar function. Based on this knowledge, we found more genes related to the pathogenesis of osteosarcoma and these genes could exert similar function as Runx2, a risk factor confirmed in osteosarcoma, this study may help better understand the genetic mechanism and provide new molecular markers and therapies for osteosarcoma.

Posterior pedicle screws combined with shortening and release techniques for lumbar and thoracolumbar adolescent idiopathic scoliosis

Objective:  To prospectively evaluate the clinical and radiographic effects of posterior surgery with wide posterior shortening release and segmental pedicle screws techniques in a consecutive group of patients with thoracolumbar /lumbar adolescent idiopathic scoliosis.