Yitao Ding

Degenerative lumbar scoliosis in Chinese Han population: prevalence and relationship to age, gender, bone mineral density, and body mass index.

PurposeTo investigate the prevalence of degenerative lumbar scoliosis (DLS) in Chinese Han population, as well as its correlation with age, gender, bone mineral density (BMD), and body mass index (BMI); and to determine factors that might affect the curve severity.MethodsA prospective study was performed on adults visiting the dual-energy X-ray absorption clinics for physical examination from January 2011 to March 2012. 2,395 subjects aged older than 40xa0years and having no history of previous spinal trauma, surgeries or scoliosis, were enrolled in this study. A logistic regression analysis was performed to determine the independent variables related to the presence of scoliosis. Besides, the relationship between curve severity and these variables was also analyzed with partial linear correlation analysis.ResultsThe prevalence of DLS was approximately 13.3xa0%. The logistic regression analysis showed that age, T score, and gender all had remarkable correlation with the occurrence of DLS, with the odd ratios being 4.2, 1.5, and 1.6, respectively. According to the receiver operating characteristics curve, the best dividing point for age and T score of female subjects was 65 and −2.0, respectively. Partial linear correlation analysis indicated that there existed no obvious correlation between the above variables and the severity of scoliosis.ConclusionThe prevalence of DLS in Chinese Han population aged older than 40xa0years was approximately 13.3xa0%, which had a significant correlation with age, gender, and BMD. Osteopenia, gender of female, and aged older than 65xa0years could contribute to the presence of DLS. The curve severity was not associated with age, gender, BMI, or BMD.

Validation and reliability analysis of the new SRS-Schwab classification for adult spinal deformity.

Study Design. An inter- and intra-observer reliability study. Objective. To determine the inter- and intra-observer reliabilities of the new SRS-Schwab system for classifying adult spinal deformity (ASD) using nonpremarked cases. Summary of Background Data. Schwab et al reported excellent inter- and intra-observer reliability and interobserver agreement for classification based on curve type and 3 modifiers. Methods. A total of 102 patients with ASD were included in this study, which was conducted from February 2009 to January 2012. Long-cassette standing posterior-anterior and lateral radiographs of the spine and the pelvis were obtained from patients with ASD in the fist-on-clavicle position. All 102 cases were classified according to the new SRS-Schwab classification by 4 observers. After a 2-week interval, the same classification was independently repeated by each observer with the cases in a different randomly assigned order. The Fless &kgr; coefficient was calculated to test the inter- and intra-observer reliabilities of the new SRS-Schwab classification. Results. With the new SRS-Schwab classification system, 12 patients were classified as having a type T curve, 30 cases as having a type L, 45 cases as having a type D, and 15 cases as having a type S. For overall classification, the mean &kgr; value was 0.73 for interobserver reliability and 0.83 for intraobserver reliability. Disagreements occurred most often when differentiating type T curves from type L curves and when determining the pelvic incidence minus lumbar lordosis modifier. Conclusion. With the nonpremarked cases, this new SRS-Schwab system for patients with ASD could achieve good to excellent intra- and inter-observer reliability, but the definition of thoracic or lumbar curves was still predisposed to confusion. Overall, the SRS-Schwab system is a simple and clear classification system with incorporated spinopelvic parameters, which significantly increase its value for practical usage.

Unanticipated revision surgery in adult spinal deformity: an experience with 815 cases at one institution.

Study Design. Retrospective case series. Objective. This study reviewed the overall prevalence and indications of revision surgical procedures for adult scoliosis in a single institution. In this largest single-institution series, revision surgery in adult scoliosis was required for a relatively low proportion of cases (7.61%). The main indications were implant breakage, deformity progression, and infection. Summary of Background Data. Spine fusion is considered as the final therapeutic intervention in the management of adult scoliosis. However, reports on the repeat surgical intervention of adult scoliosis predate the use of advanced instrumentation systems. Methods. The scoliosis database of our center was searched, and all cases with index spinal fusion surgical procedures performed for adult scoliosis from 1998 to 2011 with the follow-up period of more than 2 years were identified. The clinical data and radiographs of patients were reviewed to provide information on the indication of initial operation and any subsequent revision surgery. A total of 815 patients were identified, with a mean age of 30.49 years (range, 20–76 yr). The mean follow-up periods were 6.4 years (range, 2–15 yr) for the entire cohort and 7.6 years (range, 2.5–12 yr) for the subset of the cohort requiring revision. Results. The patients exhibiting multiple reasons for revision were classified under primary reason and subjected to subsequent analysis. Among the 815 patients, 62 (7.61%) underwent at least 1 revision surgery. The most common reasons for revision were implant breakage (23/62; 37.1%), deformity progression (10/62; 16.1%), and infection (9/62; 14.5%). The other indications were pseudarthrosis (n = 8), implant dislodgement (n = 6), junctional kyphosis (n = 5), and neurological deficit (n = 1). Revision rate was significantly higher in patients older than 40 years (15.23% vs. 5.87%), in patients with degenerative or congenital scoliosis (15.12% vs. 12.82%), or in patients with hybrid constructs (12.12% vs. 5.82%). Conclusion. In this largest single-institution series, revision surgery after index spinal fusion in patients with adult scoliosis was required for a relatively low proportion of surgical cases (7.61%). The main indications for revision were implant breakage, deformity progression, and infection. Level of Evidence: 3

Nutrition support with glutamine dipeptide in patients undergoing liver transplantation.

AIMnThe effect of total parenteral nutrition (TPN) support supplemented with alanyl-glutamine (Ala-Gln) dipeptide was investigated in a randomized, controlled clinical trial.nnnMETHODSnSixty-five patients with the diagnosis of end-stage liver disease or hepatic cellular carcinoma admitted for orthotopic liver transplantation were randomly divided into 3 groups: diet group (n = 21), TPN group (n = 22), and Gln group (n = 22). Patients in the TPN and Gln groups received isocaloric and isonitrogenous TPN for 7 days. Venous heparin blood samples were obtained for assay on days 2 and 9 after surgery; we performed routine pathologic tests.nnnRESULTSnCompared with the results on day 9 in the TPN group, there was a significant increase in the prognostic nutrition index and in prealbumin among the Gln group. Aspartate aminotransferase improved significantly by Gln treatment compared with traditional TPN support (P < .05). The pathologic results also showed Gln supplementation to reduce hepatic cell injury. A significant decrease in postoperative hospital stay was observed in the Gln group.nnnCONCLUSIONSnPosttransplant TPN support greatly improved protein metabolism and nutritional state of patients. TPN with Ala-Gln helped to improve synthetic function and to reduce the injury to a transplanted liver.

Posterior second sacral alar iliac screw insertion: anatomic study in a Chinese population

ObjectiveTo provide radiographic parameters for optimal placement of posterior second sacral alar iliac (S2AI) screw for instrumentation and fusion of scoliosis to the second sacral level in a Chinese population.MethodsS2AI screw trajectories were mapped on three-dimensional computed tomography (3DCT) reconstructions of 60 normal adult pelvises. 1xa0mm inferior and 1xa0mm lateral to the S1 dorsal foramen were chosen as the entry point, and ideal S2AI screw trajectories were explored by rotating and cutting the 3D pelvis, ensuring that the trajectories were of maximum length and width. The directions and depth of these determined trajectories were then measured.ResultsThe ideal S2AI screw trajectories could be found in each pelvis. The left and right screw trajectory parameters for males were shown as follows: angulation was L 29.15xa0±xa08.60° vs. R 29.96xa0±xa08.28° (pxa0=xa00.286) caudally in the sagittal plane and L 36.49xa0±xa03.14° vs. R 37.16xa0±xa03.14° (pxa0=xa00.165) laterally in the transverse plane. The maximal and intrasacral lengths of trajectory were L 121.25xa0±xa08.33 vs. R 120.63xa0±xa07.54xa0mm (pxa0=xa00.460) and L 26.20xa0±xa03.31 vs. R 26.92xa0±xa04.76xa0mm (pxa0=xa00.268). The entry point was L 28.87xa0±xa03.33 vs. R 29.79xa0±xa03.55xa0mm (pxa0=xa00.186) lateral to the second sacral midline, and L 44.14xa0±xa011.87 vs. R 43.89xa0±xa012.53xa0mm (pxa0=xa00.687) underneath the skin. The trajectories for females were more caudal (L: 34.50xa0±xa06.56° vs. 29.15xa0±xa08.60°, pxa0=xa00.009; R: 35.72xa0±xa07.53° vs. 29.96xa0±xa08.28°, pxa0=xa00.007) in the sagittal plane, but the lateral angulation in the transverse plane showed no difference between genders (pxa0>xa00.05). The female iliac medullar cavities were obviously narrower than those of males (L: 14.76xa0±xa02.46 vs. 16.98xa0±xa03.52, pxa0=xa00.006; R: 14.94xa0±xa02.60 vs. 17.00xa0±xa02.81, pxa0=xa00.005). Although the average maximal length of trajectories for females were about 5xa0mm shorter than those of males, intrasacral length were equal to those of males. Furthermore, both the distance from entry point to the S2 midline and skin in the transverse plane showed no difference between genders.ConclusionThe feasibility to insert S2AI screws to the sacrum and ilium in an Asian population along with the ideal entry angle and length of trajectory were identified for clinical practice.

Validation of the Simplified Chinese version of the Core Outcome Measures Index (COMI).

PurposeTo translate the Core Outcome Measures Index (COMI) into Simplified Chinese and then validate it for Mainland Chinese patients with low back pain (LBP).MethodsA total of 120 consecutive patients with LBP >3xa0months who visited our outpatient clinic from December 2011 to March 2012 were asked to complete a questionnaire booklet including the following: (1) the Roland Morris disability questionnaire (RMQ) (Fan et al. in Spine 37(10):875–880, 2012), (2) the Short Form Health Survey (SF-36) (Zhang et al. in Int J Med Sci 9(7):521–526, 2012), (3) the Oswestry Disability Index (ODI) (Liu et al. in Spine 34(11):1211–1216, 2009), (4) visual analogue scale (VAS) measure of pain, and (5) COMI. These patients were also asked to complete a second COMI questionnaire and a transition questionnaire (5-point Likert scale: better, a little better, no change, a little worse, worse) and to return the second COMI questionnaire via mail within 1xa0month.ResultsThe floor effects for the COMI items ranged from 5.8 to 12.5xa0%. High values (28.3, 27.5, and 25.8xa0%, respectively) were found for symptom-specific quality of life, social disability, and work disability. Regarding the ceiling effects, the social and work disabilities were relatively high at 17.5 and 24.2xa0%, respectively. For other items, the values ranged from 0 to 14.2xa0%. Neither floor nor ceiling effects were found for the COMI summary score. Excellent correlations were found between the COMI pain scores and VAS scores (Rhoxa0=xa00.89) and between the COMI pain and the SF-36 bodily pain domain (Rhoxa0=xa00.84). Other individual items and summary scores showed a very good correlation (Rhoxa0=xa00.54–0.72) with the corresponding questionnaires except for “symptom-specific well-being” (0.31–0.45). One-way repeated measures ANOVA was used to determine the intraclass correlation coefficient (ICC). The ICC for the entire COMI score was 0.91 (95xa0% CI 0.85–0.94) and 0.81–0.86 for the two pain scores (back and leg). The “minimum detectable change’’ (MDC 95xa0%) for the COMI summary score was 1.91 points. No significant difference in the mean values was found for the repeated scores of individual items or the summary score.ConclusionThe Simplified Chinese version of COMI showed satisfactory reliability and good psychometric properties. This concise questionnaire is suitable for widespread use in Mainland China.

Misplacement pattern of pedicle screws in pediatric patients with spinal deformity: a computed tomography study.

Study Design: A retrospective study. Objective: To assess the accuracy and safety of the placement of pedicle screws (PSs) on pediatric patients with congenital scoliosis younger than 10 years through postoperative computed tomography scanning. Summary of Background Data: The accuracy of the placement of PSs in adolescent and adult population with various spinal problems has been thoroughly studied. As to pediatric patients with congenital scoliosis, the related studies were inadequate. Methods: A retrospective review was carried out on 96 pediatric patients with congenital scoliosis younger than 10 years, who received posterior instrumentation from February 2006 to June 2012. Postoperative computed tomography scan was utilized to assess the accuracy of PS placement. Pedicle perforations were classified as medial, lateral, or anterior and categorized into 1 of the 4 grades: grade 1, ⩽2 mm; grade 2, 2.1–4.0 mm; grade 3, 4.1–6.0 mm; and grade 4, ≥6.1 mm. The positions of screws were also classified as acceptable (fully contained screws or with screws either ⩽2 mm of medial wall perforation or ⩽6 mm of lateral wall perforation and without impingement of visceral organs) or unacceptable. The variables of PS position as defined by fully contained were statistically examined using the Fisher (2-tailed) exact test with regard to: (1) side of the curvature (convex or concave); (2) region (thoracic or lumbar); (3) magnitude of the curvature (<80 or ≥80 degrees); (4) apical region and overall; (5) deformed vertebrae versus normal vertebrae. Results: A total of 625 screws were inserted; 512 screws (81.9%) were fully contained within the cortical boundaries of the pedicle. Five hundred and sixty-nine (91.0%) screws were regarded as acceptably positioned, whereas 56 (9.0%) as unacceptably positioned. Among the 625 screws inserted, 317 were inserted in the thoracic spine, of which 67 (21.1%) led to perforations, and 308 screws were inserted in the lumbar spine, of which 46 (14.9%) led to perforations. The breach rate was found to be higher in thoracic spine than in the lumbar spine (P<0.05). Of the 625 screws inserted, 306 screws were inserted on the concave side of the curve, of which 50 (16.3%) led to perforations, and 319 were inserted on the convex side, of which 63 (19.7%) led to perforations. There is no difference with regard to the breach rates between the concave side and the convex side of the curve (P>0.05). Of the 625 screws, 328 were inserted in patients with a Cobb angle <80 degrees, of which 41 (12.5%) screws perforated the pedicles, and 297 screws were inserted in the patients with a Cobb angle >80 degrees, of which 72 (24.2%) screws perforated the pedicles. The breach rate was higher in the patients with the Cobb angle >80 degrees than in the patients with the Cobb angle <80 degrees (P<0.05). One hundred and fifty-four screws were inserted in the apical vertebrae, of which 57 (37.1%) screws perforated the pedicle walls. The breach rate in apical vertebrae was higher than the overall (55/154 vs. 113/625) (P<0.05). Among the 625 screws, 252 screws were inserted in the deformed vertebrae, of which 58 (23.0%) perforated the pedicle walls, and 373 screws were inserted in the normal vertebrae, of which 55 (14.7%) perforated the pedicle walls. The breach rate in the deformed vertebrae was higher than the normal vertebrae (P<0.05). Conclusions: PSs insertion in pediatric patients with congenital scoliosis was less accurate than that in adult patients. However, the safety of placement was quite satisfactory. The possibility of pedicle breaching increased when placing PSs at deformed vertebra, on the apex of the curve, and in the thoracic spine, which reminds surgeons to be more cautious when placing PSs in these regions.

Scoliotic posture as the initial symptom in adolescents with lumbar disc herniation: its curve pattern and natural history after lumbar discectomy

BackgroundThere have been few studies focusing on the curve pattern of scoliosis caused by lumbar disc herniation (LDH) in adolescents and the natural history of scoliosis after discectomy. The current study was carried out to identify the curve pattern of scoliosis and investigate the effect of posterior discectomy on the curve improvement in adolescents with LDH.MethodsThis review focused on a group of 26 adolescents with LDH who initially presented to our clinic for evaluation of scoliosis, followed by posterior discectomy between 2000 and 2009. Radiographic measurements included curve pattern, specific curve features, trunk shift, and sagittal profile. The correlation between the side of disc herniation and the direction of lumbosacral curve and the trunk shift was evaluated.ResultsA typical curve pattern was initially identified in all of the patients as a short lumbosacral curve accompanied with a long thoracic or thoracolumbar curve toward the opposite side. 23 of 26 patients (88.5%) had a trunk shift more than 2.0 cm away from the midline, showing a poor coronal balance. A relatively straight sagittal profile was noted in all the patients. 84.6% (22/26) patients had a disc herniation at the convex side of lumbosacral curve. Similarly, 73.1% (19/26) patients showed a trunk shift toward the opposite side of disc herniation. All of the patients had an marked curve improvement immediately after discectomy. In the 17 patients with a more than 2-year follow-up, only two had a residual lumbosacral curve greater than or equal to 20 degrees. The mean ODI improved from 21.4% before surgery to 7.3% at the final follow-up.ConclusionsA short lumbosacral curve accompanied with a long thoracic or thoracolumbar curve toward the opposite side, and a relatively straight sagittal profile have been noted in all the patients. The direction of lumbosacral curve and trunk shift was related to the side of disc herniation. A majority of patients have a small curve size while assosiated with a significant coronal imbalance. Earlier decompression can provide a greater opportunity for spontaneous correction of scoliosis.

Coronal curvature and spinal imbalance in degenerative lumbar scoliosis: disc degeneration is associated.

Study Design. A retrospective radiographical study. Objective. To determine the association between disc degeneration and spinal malalignment on both coronal and sagittal planes in patients with degenerative lumbar scoliosis (DLS). Summary of Background Data. In recent years, a thorough understanding of spinal coronal balance and sagittal alignment has become more and more important in treating patients with DLS. Although degeneration of discs has been generally accepted as the main cause of DLS, to date no study has documented the relationships between disc degeneration and the curve magnitude as well as spinal imbalance. Methods. In this study, 57 patients with DLS were recruited. Degeneration of the apical disc, lower end vertebral (EV) discs and regional lumbar discs (L1–L2 and L5–S1) were quantitatively evaluated by the Pfirrmann score based on T2-weighted magnetic resonance images. Radiographical parameters including Cobb angle, coronal trunk shift, sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence, pelvic tilt, and sacral slope were measured from long-cassette standing upright radiographs. Subjects were assigned to 4 groups: both coronal and sagittal balanced (C+ S+); coronal imbalanced but sagittal balanced (C− S+); coronal balanced but sagittal imbalanced (C+ S−); and both coronal and sagittal imbalanced (C− S−). The Spearman correlation was used to identify the relationship between the Pfirrmann score of disc degeneration and radiographical parameters. Analysis of variance 2×2 factorial design was performed to identify the decisive factors affecting coronal and sagittal balance. Results. On the basis of the criteria for each group, 19 patients were assigned to group A (C+ S+), 10 patients to group B (C− S+), 11 patients to group C (C+ S−), and 17 patients to group D (C− S−). The Pfirrmann score of regional lumbar disc degeneration strongly correlated with Cobb angle, SVA, TK, and LL (r = −0.364, −0.386, 0.283, and 0.479, respectively, P < 0.01). Specifically, the Pfirrmann score of apical disc degeneration correlated with Cobb angle, whereas degeneration of lower EV discs correlated with SVA, TK, and LL. On the basis of analysis of variance 2 × 2 factorial design, the score of the lower EV disc degeneration significantly correlated with sagittal balance (P < 0.05). Conclusion. This study demonstrated that the lower EV disc degeneration strongly correlated with sagittal imbalance in patients with DLS, implying that disc degeneration may be regarded as a potential risk factor for sagittal imbalance. This result strengthened the importance of not selecting the lower EV as the lower instrumented vertebra during the surgical decision making, which may lead to deterioration of sagittal balance. Disc degeneration was also strongly correlated with sagittal malalignment, as demonstrated by a more positive SVA, decreased TK and LL, providing insight into reasons for low quality of life in elderly patients with DLS. Level of Evidence: 3

Vertebral Rotatory Subluxation in Degenerative Scoliosis: Facet Joint Tropism Is Related

Study Design. A cross-sectional study. Objective. To identify facet tropism as one of the possible risk factors leading to vertebral rotatory subluxation (VRS). Summary of Background Data. VRS has been considered as one of the prognostic factors for degenerative scoliosis. Although several risk factors of VRS, including age and Cobb angle, have been investigated, few studies exist that have evaluated the correlation between VRS and anatomical structures of the vertebral column. Methods. This retrospective study recruited 23 patients diagnosed with degenerative lumbar scoliosis with VRS and 20 patients with degenerative scoliosis without VRS. The lateral translation on coronal radiographs was measured and 5 mm was used as the cutoff value to define rotatory subluxation. Computed tomographic scans for facet joints were made for all lumbar levels. The difference between right and left facet angles was recorded as &Dgr;FA. Facet tropism was defined as a difference between the bilateral facet angles of more than 10°. Results. In this study, VRS was most commonly found at the L3–L4 level (49%) and, with decreasing frequency at L2–L3 (24%), L4–L5 (20%), and L1–L2 (7%). On the convex side of the main curve, face joints at levels with VRS were more coronally oriented compared with those at levels without VRS (41.64°± 11.65° vs. 36.30°± 10.99°, P = 0.034). &Dgr;FA was also significantly different between levels with and without VRS (P = 0.005). A strong correlation was found between &Dgr;FA and lateral translation, with a coefficient of 0.33 (P < 0.001). In addition, &Dgr;FA and a larger Cobb angle were found to be significantly associated with VRS based on binary regression analysis, with an odds ratio of 4.68 and 2.14, respectively. Conclusion. Facet tropism was more significantly observed at levels with VRS. On the convex side of the main curve, facet joints at levels with VRS were more coronally oriented. A larger Cobb angle and severe facet tropism in degenerative scoliosis should be considered to be related to VRS.