Scoliocorrector Fatma-UI for correction of adolescent idiopathic scoliosis: Development, effectivity, safety and functional outcome

BACKGROUND Adolescent idiopathic scoliosis remains a major problem due to its high incidence,high risk,and high cost.One of the aims of the management in scoliosis is to correct the deformity.Many techniques are available to correct scoliosis deformity;however,they are all far from ideal to achieve three-dimensional correction in scoliosis.AIM To develop a set of tools named Scoliocorrector Fatma-UI(SCFUI)to aid threedimensional correction and to evaluate the efficacy,safety,and functional outcome.METHODS This study consists of two stages.In the first stage,we developed the SCFUI and tested it in finite element and biomechanical tests.The second stage was a single-blinded randomized clinical trial to evaluate the SCFUI compared to direct vertebral rotation(DVR).Forty-four subjects with adolescent idiopathic scoliosis were randomly allocated into the DVR group(n=23)and SCFUI group(n=21).Radiological,neurological,and functional outcome was compared between the groups.RESULTS Finite element revealed the maximum stress of the SCFUI components to be between 31.2-252 MPa.Biomechanical analysis revealed the modulus elasticity of SCFUI was 9561324±633277 MPa.Both groups showed improvement in Cobb angle and sagittal profile,however the rotation angle was lower in the SCFUI group(11.59±7.46 vs 18.23±6.39,P=0.001).Neurological and functional outcome were comparable in both groups.CONCLUSION We concluded that SCFUI developed in this study resulted in similar coronal and sagittal but better rotational correction compared to DVR.The safety and functional outcomes were also similar to DVR.

The Outcome of Posterior Spinal Fusion and Instrumentation of Adolescent Idiopathic Scoliosis without Wound Suction Drainage

Background: In spine surgery postoperative closed suction drainage is used to decrease the potential risks of wound hematoma formation, and reduces the risk of infection, cord compression and neurologic deficit. However, the efficacy of drains used for this purpose in adolescent idiopathic scoliosis is controversial. The purpose of this study is to evaluate outcomes of patients after posterior spinal fusion with instrumentation for adolescent idiopathic scoliosis without wound suction drainage. Methods: A total of 66 Patients who underwent posterior spinal fusion and instrumentation for the correction of Adolescent idiopathic scoliosis without the use of drain from January 2012 to January 2021 were included. Wound dehiscence, wound hematoma, infection, preoperative and postoperative hemoglobin levels and need for transfusion were described as frequency and mean values. Results: The average age was 15.06 years. Hospital stay was 2.2 days. Patients were followed-up over 50.21 months. There was no deep infection, wound hematoma. The difference between just postoperative and three days after operation hemoglobin levels was not significant and no need for transfusion. Only 3 (4.5%) cases with superficial skin infection and 4 (6%) cases with skin and Wound dehiscence were treated with dressing and antibiotics with full recovery. Conclusion: Without using drain for patients with idiopathic scoliosis who underwent posterior spinal fusion and instrumentation, no increase in blood loss, transfusion requirements, wound infection, skin dehiscence, and wound hematoma was observed.

Research progress on the safety of nail placement in adolescent idiopathic scoliosis surgery

Adolescent idiopathic scoliosis is a spinal deformity with unknown etiology and high incidence,especially in adolescent females.If scoliosis patients do not get effective treatment in the early stage,the degree of scoliosis will continue to worsen with the growth of age or the rapid development of scoliosis in a short time,and the appearance deformities such as high and low shoulders and razor back will gradually appear,which can affect the cardiopulmonary function and even shorten life expectancy.It has a great impact on the physical and mental health of the patients.Mild scoliosis is often well controlled by bracing,and moderate to severe scoliosis deformity often requires scoliosis corrective surgery.In adolescent idiopathic scoliosis correction,pedicle screws offer better stability and firmness,stronger orthopedic force,and lower incidence of related complications caused by instruments than traditional hook and conical internal fixation instruments.At the same time,scoliosis patients have uneven development of the left and right sides of the vertebral body,narrow diameter of concave pedicle and varying degrees of rotation of parietal vertebra,resulting in changes in the position of important anatomical structures such as spinal cord and thoracic aorta in the spinal canal.It makes it difficult to place pedicle screws,resulting in a high misplacement rate.How to improve the safety of screw placement,reduce the misplacement rate and the risk of spinal cord,nerve root,blood vessels,viscera and so on,has always been the focus of spinal surgeons.This paper summarizes the related literature on the effects of new techniques such as pedicle anatomy,complications of nail placement and computer navigation,and 3D guided template on the accuracy of screw placement in adolescent idiopathic scoliosis patients,and the safety of nail placement.In order to provide reference for clinical practice.

Accuracy of screw placement in the apical region of Lenke 1 adolescent idiopathic scoliosis surgery using a calibration technique for the intraoperative navigation error

Objective:To study the position and the grade of screw perforation in the apical region of adolescent idiopathic scoliosis(AIS)surgery using a calibration technique for the intraoperative navigation error,and to analyze the related factors of navigation deviation and the clinical significance of the calibration technique.Methods:From 2017 to 2020,a total of 60 Lenke 1 AIS surgical cases were enrolled in this research.The 30 cases received surgery using the intraoperative navigation system(Navigation group)and another 30 cases were assisted with intraoperative navigation system with calibration technique(Calibration group)for the intraoperative navigation error.The basic information and radiological data of the both groups were all recorded.According to the Fu Chang-feng’s pedicle channel classification system,the pedicle on the apical region of the two groups was classified.And then the accuracy of screw placement of the two groups was evaluated according to the Rao’s classification.Results:A total of 600 screws were placed in the two groups.The 297 and 303 pedicle screws were implanted in the navigation group and the calibration group,respectively.In the apical region of the calibration group,the rates of the grade 0 screw placement in type A,B and C pedicle were 95.7%,86.7%and 68.9%respectively.It was a statistically significant difference from the 73.9%,66.9%and 30.0%in the navigation group respectively(P<0.05).In the calibration group,the rates of the medial cortical perforation in the type A,B,C and D pedicle were 0%,1.6%,1.6%and 0%,respectively.The corresponding rates were 16.3%,16.9%,30.0%and 47.6%in the navigation group,respectively.Moreover,in the concave side of the apical region of the calibration group,the rates of the medial cortical perforation in the type A,B,C and D pedicle were 0%,3.6%,2.6%and 0%,respectively.Compared with the calibration group,the corresponding rates were higher in the navigation group(34.4%,25.9%,37.2%and 60.0%,respectively).No serious complications such as spinal cord or neurovascular injury occurred for the two groups.Conclusion:Compared with the intraoperative navigation system,the calibration technique for the intraoperative navigation error could provide the higher accuracy of pedicle screw placement in the apical region of the major curve,the lower medial cortical perforation rate,the less screws misplacement rate on the concave side and the less complication rate of the severe Lenke 1 AIS patients.

Posterior Selective Thoracic Fusion in Adolescent Idiopathic Scoliosis Patients:a Comparison of All Pedicle Screws versus Hybrid Instrumentation

Objective To analyze the influence of segmental pedicle screws versus hybrid instrumentation on the correction results in adolescent idiopathic scoliosis patients undergoing posterior selective thoracic fusion. Methods By reviewing the medical records and roentgenograms of adolescent idiopathic scoliosis patients who underwent selective thoracic fusion from February 2000 to January 2007 in our hospital, the patients were divided into 2 groups according to different instrumentation fashions： Group A was hook-screw-rod （hybrid） internal fixation type, Group B was screw-rod （all pedicle screws） internal fixation type, and the screws were used in every segment on the concave side of the thoracic curve. The parameters of the scoliosis were measured and the correction results were analyzed. Results Totally, 48 patients （7 males, 41 females） were included, with an average age of 14.4 years old and a mean follow-up time of 12.3 months. Thirty and 18 patients were assigned to group A and group B, respectively. The mean preoperative coronal Cobb angles of the thoracic curve were 48.8° and 47.4°, respectively. After surgery, they were corrected to 13.7° and 6.8°, respectively. At final follow-up, they were 17.0° and 9.5°, with an average correction rate of 64.6% and 79.0%, respectively, and the correction rate of group B was significantly higher than that of group A （P=0.003）. The mean preoperative coronal Cobb angles of the lumbar curve were 32.6° and 35.2°, respectively. After surgery, they were corrected to 8.6° and 8.3°, respectively. At final follow-up, they were 10.3° and 11.1°, with an average correction rate of 66.8% and 69.9%, respectively, and the correction rate of group B was significantly higher than that of group A （P=0.003）. The correction loss of the thoracic curve and lumbar curve in the 2 groups were 3.1° and 1.8°, 2.4° and 2.4°, respectively. No significant difference was noted （both P〉0.05）. The decompensation rate at final follow-up in these 2 groups were 4% （1/25） and 7.1% （1/14） respectively, with no significant difference （P〉0.05）.

Increased Expression of Receptor Activator of Nuclear Factor-κB Ligand in Osteoblasts from Adolescent Idiopathic Scoliosis Patients with Low Bone Mineral Density

Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown.The purpose of this study was to examine the relationship between the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) levels in osteoblasts (OBs) from AIS patients with low BMD and with comparison made between the patients and controls.Twenty AIS patients and eight age-matched controls were included in the present study.The BMD of lumbar spine and proximal femur was measured in all subjects.OBs from the cancellous bone of each subject was harvested and primarily cultured.The mRNA and protein expression of RANKL and OPG in OBs was detected by RT-PCR and Western blotting.The results showed BMD was lower in AIS patients than in controls.A significantly higher mRNA and protein expression of RANKL was observed in OBs from AIS patients,while no significant difference was found in the expression of OPG between AIS patients and controls.As a result,RANKL/OPG ratio in patients with AIS was remarkably higher than controls.Our study preliminarily demonstrated expression of RANKL was higher in OBs from AIS patients with low BMD as compared with controls,suggesting the unbalanced RANKL/OPG ratio caused by an over-expression of RANKL in OBs may be responsible for the low BMD in AIS patients.

POSTERIOR SELECTIVE THORACIC FUSION IN ADOLESCENT IDIOPATHIC SCOLIOSIS

To define the criteria of posterior selective thoracic fusion in patients with adolescent idiopathic scoliosis. Methods By reviewing the medical records and roentgenograms of 17 patients with adolescent idiopathic scoliosis who un-derwent posterior selective thoracic fusion, the curve type, Cobb angle, apical vertebral rotation and translation, trunk shift, and thoracolumbar kyphosis were measured and analyzed. Results There were 17 King type Ⅱ patients (PUMC type: Ⅱb1 13, Ⅱc3 4). The coronal Cobb angle of thoracic curve be-fore and after operation were 56.9°and 21.6° respectively, the mean correction rate was 60.1%. The coronal Cobb angle of lumbar curve before and after operation were 34.8° and 12.1° respectively, and the mean spontaneous correction rate was 64.8%. At final follow-up, the coronal Cobb angle of thoracic and lumbar curve were 23.5° and 15.2° respectively, there were no significant changes in the coronal Cobb angle, apical vertebral translation and rotation compared with that after operation. One patient had 12° of thoracolumbar kyphosis after operation, no progression was noted at final follow-up. There was no trunk decompensation or deterioration of the lumbar curve. In this group, 3.9 levels were saved compared with fusing both the th-oracic and lumbar curves. Conclusion Posterior selective thoracic fusion can be safely and effectively performed in King type Ⅱ patients with a mo-derate and flexible lumbar curve, which can save more mobile segments and at the same time can maintain a good coronal and sagittal balance.

Altered physiology of mesenchymal stem cells in the pathogenesis of adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis is the most common spinal deformity during puberty,especially in females.It is characterized by aberrant skeletal growth and generalized reduced bone density,which is associated with impaired bone mineral metabolism.Despite recent progress in multidisciplinary research to support various hypotheses,the pathogenesis of Adolescent idiopathic scoliosis is still not clearly understood.One of the hypothesis is to study the role of mesenchymal stem cells due to its involvement in the above-mentioned bone metabolic abnormalities.In this review,we will summarize reported literatures on the role of mesenchymal stem cells,particularly in the pathogenesis of Adolescent idiopathic scoliosis.In addition,we will describe the research on mesenchymal stem cells of Adolescent idiopathic scoliosis performed using bioinformatics tools.

Pedicle Screw Insertion for Concave Side of Proximal Thoracic Curve in Adolescent Idiopathic Scoliosis

Background: Insertion of the pedicle screws (PS) into the proximal thoracic spine is occasionally challenging owing to the small size of the pedicles and the proximity to the spinal cord. An appropriate anchor placement method for the concave side of the proximal thoracic curve has not been established yet. This study aimed to evaluate the pedicle size and position of PS on the concave side of the proximal thoracic curve in patients with adolescent idiopathic scoliosis (AIS). Methods: Forty consecutive patients with AIS who underwent correction and fusion with all PS constructs, including the proximal thoracic curve in the fusion area, were included. After identifying the screws inserted on the concave side of the proximal thoracic curve, the pre-operative morphology and postoperative position of the inserted PS, including the end vertebrae, were analyzed using computed tomography (CT). Screw perforations were categorized into four grades depending on the degree of perforation from the pedicle wall on postoperative CT and were classified using an outcome-based classification. Results: A total of 109 screws were inserted on the concave side of the proximal thoracic curve. The average width of all pedicles was 3.5 ± 1.1 mm. The width of 90 pedicles (83%) was Conclusion: Perforations were found in 84% of the PS on the concave side of the proximal thoracic curve;however, 93% of the PS were considered acceptable in the outcome-based classification. Thus, we conclude that the in-out-in technique may be both feasible and effective.

Impaired autophagy activity-induced abnormal differentiation of bone marrow stem cells is related to adolescent idiopathic scoliosis osteopenia

Background:Osteopenia has been well documented in adolescent idiopathic scoliosis(AIS).Bone marrow stem cells(BMSCs)are a crucial regulator of bone homeostasis.Our previous study revealed a decreased osteogenic ability of BMSCs in AIS-related osteopenia,but the underlying mechanism of this phenomenon remains unclear.Methods:A total of 22 AIS patients and 18 age-matched controls were recruited for this study.Anthropometry and bone mass were measured in all participants.Bone marrow blood was collected for BMSC isolation and culture.Osteogenic and adipogenic induction were performed to observe the differences in the differentiation of BMSCs between the AIS-related osteopenia group and the control group.Furthermore,a total RNA was extracted from isolated BMSCs to perform RNA sequencing and subsequent analysis.Results:A lower osteogenic capacity and increased adipogenic capacity of BMSCs in AIS-related osteopenia were revealed.Differences in mRNA expression levels between the AIS-related osteopenia group and the control group were identified,including differences in the expression of LRRC17,DCLK1,PCDH7,TSPAN5,NHSL2,and CPT1B.Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed several biological processes involved in the regulation of autophagy and mitophagy.The Western blotting results of autophagy markers in BMSCs suggested impaired autophagic activity in BMSCs in the AIS-related osteopenia group.Conclusion:Our study revealed that BMSCs from AIS-related osteopenia patients have lower autophagic activity,which may be related to the lower osteogenic capacity and higher adipogenic capacity of BMSCs and consequently lead to the lower bone mass in AIS patients.

Schroth exercises improve health-related quality of life and radiographic parameters in adolescent idiopathic scoliosis patients

Background:Finding an optimal treatment strategy for adolescent idiopathic scoliosis(AIS)patients remains challenging because of its intrinsic complexity.For mild to moderate scoliosis patients with lower skeletal growth potential(Risser 3-5),most clinicians agree with observation treatment;however,the curve progression that occurs during puberty,the adolescent period,and even in adulthood,remains a challenging issue for clinicians.The aim of the study is to investigate the efficacy of Schroth exercise in AIS patients with lower skeletal growth potential(Risser 3-5)and moderate scoliosis(Cobb angle 20°-40°).Methods:From 2015 to 2017,data of 64 patients diagnosed with AIS in Peking University Third Hospital were reviewed.Forty-three patients underwent Schroth exercise were classified as Schroth group,and 21 patients underwent observation were classified as observation group.Outcomes were measured by health-related quality of life(HRQOL)and radiographic parameters.HRQOL was assessed using the visual analog scale(VAS)scores for back,Scoliosis Research Society-22(SRS-22)patient questionnaire.Radiographic spinopelvic parameters were obtained from anteroposterior and lateral X-rays.The pre-treatment and post-treatment HRQOL and radiographic parameters were tested to validate Schroth exercise efficacy.The inter-rater reliability of the radiographic parameters was tested using the interclass correlation coefficient(ICC).The pairedt test was used to examine HRQOL and radiographic parameters.Clinical relevance between C2-C7 sagittal vertical axis(SVA)and thoracic kyphosis was analyzed using Spearman correlation.Results:In Schroth group,VAS back score,SRS-22 pain,and SRS-22 self-image domain were significantly improved from pre-treatment 3.0±0.8,3.6±0.5,and 3.5±0.7 to post-treatment 1.6±0.6(t=5.578,P=0.013),4.0±0.3(t=-3.918,P=0.001),and 3.7±0.4(t=-6.468,P<0.001),respectively.No significant improvements of SRS-22 function domain(t=-2.825,P=0.088)and mental health domain(t=-3.174,P=0.061)were observed.The mean Cobb angle decreased from 28.9±5.5°to 26.3±5.2°at the final follow-up,despite no statistical significance was observed(t=1.853,P=0.102).The mean C2-C7 SVA value decreased from 21.7±8.4 mm to 17.0±8.0 mm(t=-1.224P=0.049)and mean T1 tilt decreased from 4.9±4.2°to 3.5±3.1°(t=2.913,P=0.011).No significant improvement of radiographic parameters and HRQOL were observed in observation group.Conclusions:For AIS patients with a Risser 3-5 and a Cobb angle 20°-40°,Schroth exercises improved HRQOL and halted curve progression during the follow-up period.Both cervical spine alignment and shoulder balance were also significantly improved after Schroth exercises.We recommend Schroth exercises for patients with AIS.

Strong halo-femoral traction with wide posterior spinal release and three dimensional spinal correction for the treatment of severe adolescent idiopathic scoliosis

Background Many investigators advocate anterior release combined with halo-femoral traction and posterior fusion when treating stiff thoracic curves in patient with adolescent idiopathic scoliosis （AIS）. But the anterior operations often induce severe complications. Some surgeons choose posterior-only surgery with halo-femoral traction, posterior wide release and correction. But to the best of our knowledge, there are only rare prospective studies on these posterior-only surgeries for AIS patients who have a rigid curve more than 80~ and flexibility less than 35%. Methods Sixty-four AIS patients were recruited from September 2006 to June 2009. All patients had rigid curves and underwent spinal correction. They were randomly divided into group A （combined anteroposterior surgery） and group B （posterior-only surgery）. Images and scoliosis research society-22 questionnaire （SRS-22） scores were performed pre- and post-operation and during follow-up visits. The operation time, blood loss, hospital days, and hospital charges were compared between the two groups. Results These patients were followed for an average of 37.5 months （range, 24-65 months）. No serious complications were observed. There were no significant differences between the two groups in gender, age, preoperative radiographic data, or preoperative SRS-22 score. The average operation time, blood loss, hospital days and hospital charges in group B were less than those in group A. The SRS-22 score in group B was better than in group A at post-operation and at final follow-up. Conclusions In AIS with a rigid curve more than 80~ and flexibility less than 35%, strong halo-femoral traction with wide posterior spinal release and three dimensional spinal correction can provide better SRS-22 scores, comparable curve correction, shorter operation time, less blood loss, shorter hospital stays and lower charges when compared to combined anterior and posterior surgery.

Postoperative Disc Wedging in Adolescent Idiopathic Thoracolumbar/Lumbar Scoliosis:a Comparison of Anterior and Posterior Approaches

Objective To evaluate the different influences of anterior and posterior correction and fusion approaches upon disc wedging in adolescent idiopathic thoracolumbar/lumbar scoliosis.Methods The retrospective study was conducted with the medical records and radiographs of adolescent idiopathic thoracolumbar/lumbar scoliosis patients that underwent anterior(group A) or posterior(group B) correction and fusion surgery from December 1998 to May 2008.The correction of the main curve and changes of the disc wedging were analyzed.Results Fifty-three patients were included,26 in group A and 27 in group B.The mean coronal Cobb angles of the main curve in group A and group B were significantly corrected after surgery(P<0.05),with an average correction rate of 75.2% and 88.2%,respectively.Upon final follow-up,the coronal Cobb angles of the two groups were 18.9°±11.1° and 7.7°±5.6°,respectively,with an average correction loss of 6.8°±6.5° and 2.7°±3.3°,respectively.The coronal Cobb angle after operation and at final follow-up,and the correction rate were significantly better in group B than those in group A(P<0.05),while the coronal Cobb angle loss in group A was greater than that in group B(P<0.05).The disc wedging before operation,after operation,and at final follow-up were 3.2°±3.0°,5.7°±3.0°,and 8.6°±4.4° in group A,and 2.4°±3.2°,3.3°±3.4°,and 3.7°±3.6° in group B,respectively.Postoperative disc wedging was significantly larger compared with preoperative measurements in group A(P<0.05),but not in group B(P>0.05).The difference between disc wedging at final follow-up and that after surgery was significant in group A(P<0.05),but not in group B(P>0.05).Between the two groups,group A had larger disc angles after operation and at final follow-up(P<0.05),and a greater loss of disc angle(P<0.05).Conclusion For adolescent idiopathic thoracolumbar/lumbar scoliosis,posterior approach using all pedicle screws might produce a better result in terms of disc wedging compared with anterior approach.

Selective fusion in adolescent idiopathic scoliosis

Despite the continual evolution in the surgical treatment of adolescent idiopathic scoliosis （AIS）,the goals of surgery remain to correct and stabilize the deformity in three dimensions, to maintain equilibrium of the shoulders and trunk, and to leave as many mobile spinal segments as possible. The essence is to fuse the smallest possible number of vertebrae to maintain maximum residual mobility, but end with corrected and well-balanced spine. Selective fusion is termed when both the main thoracic and thoracolumbar/lumbar （TL/L） curves deviate completely from the midline （Figure 1）, but only the major curve （the largest Cobb measurement） is fused, leaving the minor curve unfused and mobile. For the single curve, such as thoracic, thoracolumbar, or lumbar curve, there are fewer differences of opinion amongst spinal surgeons regarding the selection of the fusion level than the surgical approach. However, the choice of fusion levels in some types of curves, such as double curves and triple controversy issue. If the fusion is incorrect, it curvature deterioration, curves remains a difficult and decision to perform selective may result in postoperative shoulder imbalance, trunk decompensation, or even produce new deformity, an early revision by extending the fusion or reducing the correction may need. The non-selective approach rarely leads to early troubles that require a second procedure and is often perceived as being safer in the short-term. But it may be more difficult in the long-term as distal degeneration is more likely. This raises the question： ＂Is it better to be safe in the short-term or take a chance avoiding later degenerative problems with a shorter motion-sparing fusion？＂ Thus, the aim of selective fusion is to identify the compensatory curves （minor curve） that will straighten spontaneously after correcting and fusing the major curve, thereby avoid the fusion of these flexible compensatory curves.

Factors as predictors for thoracic and thoracolumbar/lumbar structural curves in adolescent idiopathic scoliosis

Background Recent studies have demonstrated that the Lenke system is relatively efficient and consistent in classifying scoliosis curves. Basically, fusion should include the main curve and the structural minor curve. The criteria for defining the structural minor curve were established to help guide these decision-making process. The present study was designed to investigate predictors of the structural curve, and see whether it was possible to prevent the formation of the structural curve by interfering with influencing factors to decrease the fusion level. Methods Age, gender, Cobb angle, Perdriolle rotation, Risser sign and the number of vertebrae included in the curve, brace treatment, and curve location were recorded in 145 idiopathic scoliosis patients from July 2001 to January 2007. The patients were divided into two groups： structural and non-structural groups. Demographics and baseline characteristics were compared between the two groups as an initial screen. Logistic regression was used to analyze factors affecting the minor curve to become the structural curve. Results Compared with the non-structural group, the structural group had a higher Cobb angle （（51.34±13.61）° vs. （34.20±7.21）°, P 〈0.001 ）, bending angle （（33.94±9.92）° vs. （8.46±5.56）°, P 〈0.001） and curve rotation （（23.25±12.86）° vs （14.21±8.55）°, p 〈0.001）, and lower flexibility （（33.48±12.53）% vs. （75.50±15.52）%, P 〈0.001 ）. There was no significant difference in other parameters between the two groups. The results of the Logistic regression analysis showed that the Cobb angle （OR： 9.921, P 〈0.001） and curve location （OR： 4.119, P=0.016） were significant predictors of structural curve in adolescent idiopathic scoliosis. Every 10~ change of Cobb angle increased the possibility of turning the minor curve into the structural curve by 10-fold. And thoracic curve showed, on the average, the possibility of becoming the structural curve about 4-fold more often than did the thoracolumbar/lumbar curve. Conclusions Curve severity and curve location affect the minor curve＇s structural features in adolescent idiopathic scoliosis.

Surgical treatment for scoliosis extending to main thoracic spine by key-vertebral-screws technique (KVST)

Objective:To introduce a key-vertebral-screws technique(KVST) in the surgical treatment of scoliosis extending to main thoracic levels, and to find the role of fulcrum bending in predicting the result of surgical treatment for scoliosis by this technique. Methods: Seventeen consecutive patients with scoliosis extending to main thoracic spine,who underwent pure posterior fusion without anterior or posterior release by KVST between January 2004 and July 2005 were evaluated for fulcrum bending flexibility, surgical correction rate, fulcrum bending correction index (FBCI) in main thoracic curves. Universal Spine System (USS) instrumentation was used in 15 cases,Monarch in another 2 cases. The severity of the curves was measured by Cobb's method using Rad Work 6. 0 software. Preoperative standing AP radiographs, preoperative fulcrum bending anterioposterior (AP) radiographs, postoperative standing AP radiographs, and most recent follow-up standing AP radiographs for spine were measured and recorded. All the data were analyzed with two-sample paired t-test by Origin 7. 0 software. Results: Infection and neurological complications were not noted. No major complications were found. Just one case had some axial back pain, which got a full recovery from physiotherapy for 2 weeks. In the X-ray, there was an average correction of 71. 5% of the fused main thoracic curves, which had no significant lose of correction in final follow-up. For the whole fused main thoracic curves, the fulcrum bending flexibility were lower to operation correction rate (P = 0. 013). The average FBCI was 123%. From the data, the more rigid curves (especially fulcrum bending flexibility <50%), the more correction rate operation could get, compared with fulcrum bending flexibility. Conclusion: (1) KVST is a good method in the surgical treatment of thoracic scoliosis, which can get satisfying result with lower medical cost. (2) Fulcrum bending flexibility is lower than operative correction rate by KVST in main thoracic curves (P<0. 05). In the more rigid curves assessed by fulcrum-bending radiograph, the operative corrective could be gained, especially in the curves which FBCI is lower than 50%.

Integrated Evolving Spiking Neural Network and Feature Extraction Methods for Scoliosis Classification

Adolescent Idiopathic Scoliosis(AIS)is a deformity of the spine that affects teenagers.The current method for detecting AIS is based on radiographic images which may increase the risk of cancer growth due to radiation.Photogrammetry is another alternative used to identify AIS by distinguishing the curves of the spine from the surface of a human’s back.Currently,detecting the curve of the spine is manually performed,making it a time-consuming task.To overcome this issue,it is crucial to develop a better model that automatically detects the curve of the spine and classify the types of AIS.This research proposes a new integration of ESNN and Feature Extraction(FE)methods and explores the architecture of ESNN for the AIS classification model.This research identifies the optimal Feature Extraction(FE)methods to reduce computational complexity.The ability of ESNN to provide a fast result with a simplicity and performance capability makes this model suitable to be implemented in a clinical setting where a quick result is crucial.A comparison between the conventional classifier(Support Vector Machine(SVM),Multi-layer Perceptron(MLP)and Random Forest(RF))with the proposed AIS model also be performed on a dataset collected by an orthopedic expert from Hospital Universiti Kebangsaan Malaysia(HUKM).This dataset consists of various photogrammetry images of the human back with different types ofMalaysian AIS patients to solve the scoliosis problem.The process begins by pre-processing the images which includes resizing and converting the captured pictures to gray-scale images.This is then followed by feature extraction,normalization,and classification.The experimental results indicate that the integration of LBP and ESNN achieves higher accuracy compared to the performance of multiple baseline state-of-the-art Machine Learning for AIS classification.This demonstrates the capability of ESNN in classifying the types of AIS based on photogrammetry images.

Bone Graft Options for Spine Fusion in Adolescent Patients with Idiopathic Scoliosis

Adolescent idiopathic scoliosis （AIS） is one of the most prevalent diseases among teenagers, with an incidence rate of 1-3% worldwide, and at least 0.02% of patients require surgical treatment. The ＂gold standard＂ procedure is instrumentation and fusion of 10 or more vertebrae with forceful correction of the deformity.Although autogenous bone grafts are the ＂gold standard＂ for spine fusion, significant progress has been made in discovering bone graft alternatives, including freeze-dried allograft, demineralized bone matrix （DBM）, triosite ceramics, and bone marrow aspirate （BMA）, which have been used as substitutes for iliac crest in AIS surgery.

Numerical Simulation Method of Scoliosis Orthosis Considering Muscle Factor

Adolescent idiopathic scoliosis seriously affects the physical and mental health of adolescents.In thepast,the research on therapeutic orthosis ignored the influence of muscle factors.Aimed at this problem,basedon the principle of reverse engineering,through the spine computed tomography data model of three-dimensionalreconstruction,muscle forces around the spine are imported into the spinal muscle force model and AnyBodysoftware is used for simulation.The geometric similarity and biomechanical effectiveness of the established modelare verified.In order to obtain the relationship among the applied orthopedic force,Cobb angle and vertebraldisplacement,a finite element model conforming to spinal anatomy is established,and then the biomechanicalanalysis of the finite element model of the scoliosis is carried out.Reasonable control of paravertebral muscles canplay a positive role in orthopedic treatment,and the fitting equation can provide a reference for doctors to applythe orthopedic force on patient.