Search

Background: The presence of bridging syndesmophytes (BS) in spinal osteotomy region serves traditionally as one critical determinant for selection of osteotomy techniques. While nowadays the proportion of kyphotic ankylosing spondylitis (AS) patients receiving pedicle subtraction osteotomy (PSO) with yet mobile neighboring disc has seen a substantial increase. Literatures investigating the clinical relevance of the presence of BS on kyphosis correction and maintenance following PSO are scarce.Methods: A total of 71 thoracolumbar kyphotic AS patients treated with single-level PSO at our hospital between September 2010 and August 2014 were retrospectively reviewed, 32 of whom were stratified into the BS group (BG). The operative corrections of multiple spino-pelvic sagittal parameters were assessed. Comparison of the contribution of adjacent disc wedging to total correction per PSO segment was made between the BS and non-BS groups (NBG). The correction loss were also evaluated and compared with a minimum 2-year follow-up.Results: A significantly younger age (30.97 ± 8.28 vs. 40.31 ± 8.44 yrs., p < 0.001), smaller pelvic incidence (PI) (43.03 ± 10.60 vs. 49.36 ± 9.75°, p = 0.011), greater wedging index of osteotomized vertebra (1.17 ± 0.16 vs. 1.09 ± 0.08, p = 0.011) and larger local kyphosis (19.59 ± 10.84 vs. 13.56 ± 8.50°, p = 0.013) was observed in NBG preoperatively. Patients in BG and NBG accomplished comparable amount of kyphosis correction per PSO segment (40.22 ± 7.09 vs. 43.85 ± 8.71°, p = 0.062). However, the contribution of adjacent disc wedging to total correction per PSO was significantly larger in NBG [8.10 ± 6.19 (18.5%) vs. 1.09 ± 2.88° (2.7%), p < 0.001]. By ultimate follow-up, the global kyphosis (18.26 ± 10.97 vs. 21.51 ± 10.89°, p < 0.05) and thoracic kyphosis (37.95 ± 11.87 vs. 42.87 ± 11.56°, p < 0.05) deteriorated significantly in the NBG but not BG, so was further pelvic retroversion as represented by increased pelvic tilt (19.46 ± 8.13 vs. 23.44 ± 8.19°, p < 0.05) and decreased sacral slope (23.02 ± 9.12 vs. 18.62 ± 10.10°, p < 0.05). Loss of corrections concerning contribution of adjacent disc wedging was also larger in NBG (1.41 ± 3.27 vs. 0.22 ± 1.49°, p < 0.05).Conclusions: Our study might suggest that the evaluation and treatment methods of kyphotic AS patients needed to be fine-tuned with appropriate subgrouping by the presence of syndesmophytes with bamboo sign as they were potentially distinct groups with different PI, contributor of lordosing capability and prognosis that might require separate analysis. [ABSTRACT FROM AUTHOR]

Background: Short-term studies have demonstrated good surgical outcomes after pedicle subtraction osteotomy (PSO) in ankylosing spondylitis (AS) patients, but there is a paucity of literature focused on middle-term results, especially regarding patterns of loss of correction. The objective of this study is to assess the durability of surgical outcomes and the patterns of loss of correction in thoracolumbar kyphosis secondary to AS following lumbar PSO with over 5-year follow-up.Methods: We performed a retrospective review of 155 consecutive AS patients undergoing lumbar PSO from January 2001 to December 2011. Twenty-four patients were included with an average follow-up of 6.9 years (range, 5-15 years). Radiographical evaluations included global kyphosis (GK), lumbar lordosis (LL), sagittal vertical axis, spinal-sacral angle, kyphosis of proximal non-fused segments (KPNS), angle of fused segments (AFS), osteotomized vertebra angle (OVA), distal intervertebral disc wedging (DIDW) and proximal junctional angle. Meanwhile, clinical outcomes were assessed by the Oswestry disability index (ODI) and Numerical rating scale (NRS).Results: The average correction per PSO segment was 34.9°. Significant improvement in sagittal parameters were found postoperatively, and no obvious deterioration was noticed during the follow-up. Mild loss of correction in GK (2.82°) and LL (3.77°) were observed at the final follow-up (P < 0.05). The KPNS and DIDW increased from 26° and -5.0° postoperatively to 30° and -2.2° at the final follow-up (P < 0.05), respectively. In contrast, no significant diminishment was identified in OVA and AFS (P > 0.05). The ODI and NRS improved significantly from 20.6 and 6.6 preoperatively to 5.9 and 2.3 at the final follow-up (P < 0.05).Conclusions: PSO is an effective procedure for treating AS-related thoracolumbar kyphosis and can maintain sustained surgical outcomes during the middle-term follow-up. The loss of correction was mainly attributable to non-instrumented segments without fully ossified bridging syndesmophyte in the thoracolumbar region instead of instrumented levels. [ABSTRACT FROM AUTHOR]

Introduction: Scoliosis was found to develop in mice with neurotrophin 3 (NTF3) deficiency. Increased expression of NTF3 mRNA was detected in the paravertebral muscle in adolescent idiopathic scoliosis (AIS). Moreover, linkage study has defined a novel AIS locus on chromosome 12p and NTF3 gene located in this interval. Objectives: To investigate whether the NTF3 gene polymorphisms was associated with the susceptibility or curve progression of AIS. Materials and Methods: 362 AIS patients including 29 males (mean age 15.30 years) and 377 age-matched healthy controls including 37 males (mean age 15.86 years) were recruited. Cobb angle, risser sign some other clinical indexes were recorded. Two SNPs were selected through the HapMap database and genotyped by PCR-RFLP. Case control association study and case only association study were performed. Results: The genotype and allele frequency distribution were similar between AIS and normal control. The AIS patients with AA genotype of promoter polymorphism of NTF-3 gene (rs11063714) showed significantly lower maximum Cobb angle than the patients with AG or GG genotypes. Conclusion: The NTF3 gene polymorphism is not associated with the occurrence of AIS, but the promoter polymorphism (rs11063714) was found to be associated with the curve severity. These findings indicated that NTF3 gene might be a disease-modifying gene of AIS. Significance: Our study first reported the association between NTF3 gene polymorphism and the curve severity of AIS. Further study is required to elucidate the role of NTF3 gene in the abnormal NTF3 expression in the paravertebral muscle from AIS. [ABSTRACT FROM AUTHOR]

Introduction: Bracing is the most commonly used non-operative treatment for adolescent idiopathic scoliosis (AIS). However, it may lead to thoracic kyphosis (TK) reduction. The elastic belt (EB) has been used as brace in some AIS patients. The effect of EB on sagittal profile has not been reported. Objective: To evaluate the effect of brace and EB on the sagittal profile of AIS patients. Method: 21 patients treated with Milwaukee brace and 16 patients with Boston brace were included. Standing lateral X-ray films were obtained in three conditions: without treatment, with brace and with EB. The following parameters were measured: (1) T5-T12 TK, (2)T2-T12 TK, (3) L1-S1 lumber lordosis (LL), (4) sacral slope, (5) pelvic tilt, (6) pelvic incidence. All parameters were analyzed using paired-t test between 3 conditions. Results: The T5-T12 TK and T2-T12 TK were significantly different between 3 conditions. The TK was reduced by brace and more by EB. In Milwaukee brace subjects, L1-S1 lordosis was similar when wear EB or no treatment but significantly smaller when wear brace. No significant differences were found in pelvic parameters between the 3 conditions in both groups. Conclusion: The TK and LL were reduced by brace .The EB show more reduction effect on the TK but no effect on LL. Significance: Thoracic hypokyphosis has been thought as a risk factor of curve progression and harm to pulmonary function in AIS patients. Significant reduction effect on thoracic kyphosis should be considered when using EB as brace for AIS. [ABSTRACT FROM AUTHOR]

Introduction: Bjurei's equation has been used for height correction in scoliosis patients for decades. A significant controversy on the accuracy of height correction, however, was found in patients with severe scoliosis. Objectives: To investigate the effectiveness of Bjurei's equation in height correction in scoliosis patients with large Cobb angle. Methods: 77 patients with adolescent idiopathic scoliosis (AIS) (male 11, female 66) underwent correction surgery were recruited. Standing height (SH) and arm span were measured before and after operation. Pre- and post-operative posteroanterior radiograms of standing whole spine were taken and Cobb angle of main curve was measured. SH was corrected by either arm span (SHa) or Bjurei's equation (SHb). The pre-operative SHb was compared with SHa and postoperative SHb by Students t test. The association between the pre- and postoperative SHb difference (▵SHb) and Cobb angle was plotted. Results : The SHa was similar as SH in all subjects but significantly lower than the pre-operative SHb. Similar pre- and post-operative SHb was found in patients with Cobb angle<60°. In patients with Cobb angle >60°, however, the difference (▵SHb) increased with the increase of Cobb angle (figure 1). Conclusion : The SHa calculated by arm span equation selected may not show the real SH of AIS subjects. Bjurei's equation is suitable for height loss correction in scoliosis patients when the Cobb angle is no more than 60°. Significance: This study provides more information for the application of Bjurei's equation. [ABSTRACT FROM AUTHOR]

OBJECTIVETo describe the incidence of complications in spinal osteotomy for thoracolumbar kyphosis caused by ankylosing spondylitis (AS) and to investigate the risk factors for these complications.METHODSFrom April 2000 to July 2017, 342 consecutive AS patients with a mean age (± SD) of 35.4 ± 9.8 years (range 17-71 years) undergoing spinal osteotomy were enrolled. Patients with complications within the 1st postoperative year were identified. Demographic, radiological, and surgical data were compared between patients with and without complications. The complications were classified into intraoperative and postoperative complications.RESULTSA total of 310 consecutive pedicle subtraction osteotomy (PSO) and 37 multiple Smith-Petersen osteotomy (SPO) procedures were performed in 342 patients. Overall, 47 complications were identified in 47 patients (13.7%), including 31 intraoperative complications and 16 postoperative complications. Patients with complications were older than those without (p = 0.006). A significant difference was observed in preoperative global kyphosis (GK), lumbar lordosis (LL), sagittal vertical axis (SVA), and the correction of these radiographic parameters between patients with and without complications (p < 0.05). Two-level PSO (p = 0.022) and an increased number of instrumented vertebrae (p = 0.019) were significantly associated with an increased risk of complications.CONCLUSIONSThe overall incidence of complications was 13.7%. Age; preoperative GK, LL, and SVA; the correction of GK, LL, and SVA; 2-level PSO; and number of instrumented vertebrae were risk factors. Therefore, the potential risk of extensive surgeries with large correction and long fusion in older AS patients with severe GK should be seriously considered in surgical decision-making.

Objective: To measure the correlative parameters of vertebral pedicles from L₁ to S₁ by CT scan in the patients with thoracolumbar kyphosis secondary to ankylosing spondylitis(AS) and disc degenerative disease(DDD), and analyze their anatomical difference in order to provide the selection and placement of pedicle screw during operation., Methods: The clinical data of 30 male AS patients (AS group) with the mean age of(35.7±9.5) years (ranged, 23 to 51) and 30 male DDD patients (DDD group) with the mean age of(52.4±8.9) years(ranged, 39 to 64) underwent surgery in our institution from March 2012 to November 2014 were analyzed. The CT scans of lumbar and sacrum were performed before surgery. The parameters of vertebral pedicle from L₁ to S₁ were measured and compared, including pedicle width (PW), pedicle screw path length (PL), pedicle height (PH), pedicle transverse angle (EA), and pedicle inclined angle (FA). Paired sample t-test was used to detect the divergence in the above-mentioned data between left and right sides. In addition, results between two groups were compared using independent sample t-test., Results: The study showed that a gradual increase in the average pedicle width both AS group and DDD group from L₁ to S₁. The average PW of AS group was bigger than DDD group in L₅ and S₁( P <0.05), it was(16.47±2.66) mm and (21.76±2.97)mm vs. (14.51±2.11)mm and (18.87±2.14) mm respectively;the average PL of DDD group was smaller than AS group from L₁ to S₁( P <0.05); the both maximum of PL were in L₃ segment; the average EA of AS group was smaller than DDD group from L₁ to S₁; the average FA of AS group was significantly smaller than DDD group from L₃ to S₁, ( P <0.05), was(-2.88±10.24)°, (-7.88±10.22)°, (-7.70±10.40)°, (-5.15±10.25)° vs. (4.05±2.21)°, (7.79±4.38)°, (7.07±3.21)°, (12.62±3.21)°, respectively., Conclusions: Increasing the strength of internal fixation is feasible to insert the larger and bigger pedicle screws in low lumbar and S₁ among AS patients, while the EA should be decreased properly and the direction on the sagittal plane should be adjusted., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.

Objective: To investigate the clinical outcome and fusion rate in patients with idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement., Methods: From October 2006 to March 2008, 24 cases undergoing anterior correction and interbody fusion with calcium phosphate cement were enrolled. All of them were female, with an age ranged from 12 to 25 years. The mean Cobb angle of main curve was 46° ± 5° (range, 40° - 56°) before surgery. During operation, the most proximal and distal disc spaces were filled with rib autograft, while the remaining levels were filled with calcium phosphate cement. The interbody fusion rate, coronal correction and sagittal profile reconstruction were evaluated respectively by using χ² test and t test., Results: Interbody fusion was performed in 103 levels, including 48 levels with rib autograft and 55 levels with calcium phosphate cement. The mean follow-up period was 23.8 months (range, 12 - 33 months) in this series. At the follow-up of 6 months, fusion rate was found as 54.2% in the levels filled with rib autograft, while 50.9% in those filled with calcium phosphate cement. Solid fusion of the whole instrumented area was achieved in all cases with a minimum one-year follow-up. No instrumentation-related complications occurred. The correction rate of main curve was on an average of 76% ± 11% after surgery. A significant difference was found between preoperative and immediate postoperative value in terms of the main curve magnitude (46° ± 5° vs. 14° ± 5°, t = -26.95, P < 0.05). The correction loss of the main curve was -5.1° - 10.4° at the final follow-up. The coronal balance and lower instrumented vertebra tilting were significantly improved after operation. The thoracolumbar kyphosis was significantly reduced postoperatively (t = 3.11, P < 0.05)., Conclusion: Satisfactory bone fusion and correction maintenance can be achieved in idiopathic thoracolumbar/lumbar scoliosis treated by anterior instrumentation combined with interbody fusion using calcium phosphate cement.

Objective: To investigate whether the titrate-resistant acid phosphatase 5 (ACP5) gene polymorphisms were associated with the occurrence or curve severity of adolescent idiopathic scoliosis (AIS)., Methods: There were 372 AIS patients from January 2006 to December 2008 and 239 normal controls from March 2005 to August 2006 were recruited. The Cobb angles were ≥ 10° in all AIS patients. Using the haplotype data of Han population from the Hapmap Project, two tag SNPs (rs2229531, rs2071484) were defined for ACP5 gene. PCR-restriction fragment length polymorphism was used for the genotyping., Results: No polymorphism in rs2229531 was found in this study. The genotype and allele frequency distribution in rs2071484 were similar between AIS patients and normal controls (χ(2) = 3.336 and 1.438, P > 0.05). The mean maximum Cobb angles of different genotypes of rs2071484 in ACP5 gene were 38° ± 19° in AA, 34° ± 14° in AG and 38° ± 21° in GG, which were similar with each other among AIS patients who reached skeletal maturity or received surgery treatment (P = 0.157)., Conclusion: The ACP5 gene is neither associated with the occurrence nor the curve severity of AIS.

Objectives: To compare the sagittal profiles between thoracic idiopathic scoliosis (IS) patients with different curve progression and to determine the risk factors associated with curve progression., Methods: A total of 83 thoracic IS patients from September 2009 to May 2010 were included in this study and were divided into 3 groups according to different curve progression. All the patients did not receive any previous treatments. There were 26 skeletally mature patients whose Risser sign were 5 degree with Cobb angle < 40° in non-curve progression group (NCP group), 29 mature patients whose Risser sign were 5 degree with Cobb angle ≥ 40° in moderate curve progression group (MCP group) and 28 immature patients whose Risser sign ≤ 3 degree with Cobb angle ≥ 40° in severe curve progression group (SCP group). Five sagittal parameters, including thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic incidence (PI) and pelvic tilt (PT) were measured on the lateral X-ray films. Analysis of variance was used to compare these parameters among the 3 groups., Results: The average thoracic Cobb angle was significantly smaller in NCP group when compared with MCP group (P < 0.01) or SCP group (P < 0.01), but not significantly different between the 2 latter groups (P = 0.619). The average TK was 19° ± 7° in NCP group, 13° ± 6° in MCP group and 8° ± 5° in SCP group. The average TK was significantly smaller in SCP group when compared with MCP group (P = 0.011) or NCP group (P < 0.01), while the average TK was significantly smaller in MCP group when compared with NCP group (P < 0.01). None of the other 4 parameters showed any significant difference between the 3 groups (P > 0.05)., Conclusions: Thoracic hypokyphosis is strongly associated with curve progression in thoracic IS patients. Pelvic sagittal profile may not be involved in the underlying mechanism of curve progression in thoracic IS patients.

Objectives: Concerns regarding change in the onset and tempo of pubertal growth in ethnic Chinese have posed a need for current information on growth characteristics. This study is to update the normative data of pubertal linear growth characteristics and distribution of age at menarche in healthy Chinese adolescents., Methods: A multistage stratified cluster sampling investigation based on age and sex was designed for anthropometric data collection in 2008, including 15,204 healthy boys and 13,047 healthy girls. The PB1 mathematical growth model was utilized to derive biological parameters of the adolescent growth curves. Ages at menarche were estimated in 6,476 girls through probit analysis at the ages at which 10%, 25%, 50%, 75%, and 90% of the girls attained menarche., Results: The peak growth age (PGA) was 12.6 years for boys and 10.6 years for girls. The PHV was 6.91 cm/yr in boys and 6.69 cm/yr in girls. The overall increments of adult height since 1985 were 3.3 cm for males and 2.3 cm for females, yielded rates of 1.4 and 1.0 cm/decade, respectively. Less than 10% of Chinese girls experience onset of menses before 11.38 years, and approximately 90% of all Chinese girls are menstruating by 13.88 years, with a median age of 12.63 years., Conclusions: The current study showed an advancing trend in PGA in both Chinese boys and girls. Decreasing menarche age was also observed for Chinese girls. These updated data would serve as useful reference for interpretation of endocrine and growth status and growth disorders in Chinese during peripubertal period., (© 2010 Wiley-Liss, Inc.)

Objective: To investigate the pulmonary dysfunction patterns in patients of scoliosis associated with neurofibromatosis type I (NF1) and to identify factors affecting the pulmonary function in patients with scoliosis associated with NF1., Methods: Preoperative pulmonary function tests (PFTs) were evaluated in 100 patients with scoliosis [NF1 group, 36 cases; idiopathic scoliosis (IS) group, 64 cases] from January 2003 to June 2009. According to location of apical vertebra and dystrophic change in patients with NF1, the parameters of pulmonary function [vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), maximal voluntary ventilation (MVV)] were compared between NF1 group and IS group, and between the subgroups of NF1. The correlation between pulmonary function parameters and radiographic parameters of scoliosis was analyzed., Results: The VC, FVC, FEV1, MMEF, MVV in NF1 group and IS group were of no significant difference (P > 0.05). In NF1 patients, the pulmonary dysfunction was more severe in thoracic subgroup than non-thoracic subgroup (P < 0.05), while there was no difference between dystrophic scoliosis and non-dystrophic scoliosis (P > 0.05). The location of apical vertebra and the severity of scoliosis correlated significantly with the pulmonary dysfunction in NF1 group., Conclusions: The pattern of pulmonary dysfunction in scoliosis associated with NF1 is similar with IS. Pulmonary dysfunction is more severe in thoracic scoliosis. The location of apical vertebra and the severity of scoliosis are the risk factors influencing the pulmonary dysfunction.