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.

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.

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.

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.

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.

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.

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.

Predictors of spine deformity progression in adolescent idiopathic scoliosis: A systematic review with meta-analysis

AIM: To evaluate published data on the predictors of progressive adolescent idiopathic scoliosis(AIS) in order to evaluate their efficacy and level of evidence. METHODS: Selection criteria:(1) study design: randomized controlled clinical trials, prospective cohort studies and case series, retrospective comparative and none comparative studies;(2) participants: adolescents with AIS aged from 10 to 20 years; and(3) treatment: observation, bracing, and other. Search method: Ovid MEDLINE, Embase, the Cochrane Library, Pub Medand patent data bases. All years through August 2014 were included. Data were collected that showed an association between the studied characteristics and the progression of AIS or the severity of the spine deformity. Odds ratio(OR), sensitivity, specificity, positive and negative predictive values were also collected. A metaanalysis was performed to evaluate the pooled OR and predictive values, if more than 1 study presented a result. The GRADE approach was applied to evaluate the level of evidence.RESULTS: The review included 25 studies. All studies showed statistically significant or borderline association between severity or progression of AIS with the following characteristics:(1) An increase of the Cobb angle or axial rotation during brace treatment;(2) decrease of the rib-vertebral angle at the apical level of the convex side during brace treatment;(3) initial Cobb angle severity(> 25o);(4) osteopenia;(5) patient age < 13 years at diagnosis;(6) premenarche status;(7) skeletal immaturity;(8) thoracic deformity;(9) brain stem vestibular dysfunction; and(10) multiple indices combining radiographic, demographic, and physiologic characteristics. Single nucleotide polymorphisms of the following genes:(1) calmodulin 1;(2) estrogen receptor 1;(3) tryptophan hydroxylase 1;(3) insulin-like growth factor 1;(5) neurotrophin 3;(6) interleukin-17 receptor C;(7) melatonin receptor 1B, and(8) Scoli Score test. Other predictors included:(1) impairment of melatonin signaling in osteoblasts and peripheral blood mononuclear cells(PBMC);(2) G-protein signaling dysfunction in PBMC; and(3) the level of platelet calmodulin. However, predictive values of all these findings were limited, and the levels of evidence were low. The pooled result of brace treatment outcomes demonstrated that around 27% of patents with AIS experienced exacerbation of the spine deformity during or after brace treatment, and 15% required surgical correction. However, the level of evidence is also low due to the limitations of the included studies.CONCLUSION: This review did not reveal any methods for the prediction of progression in AIS that could be recommended for clinical use as diagnostic criteria.

The cartilage matrisome in adolescent idiopathic scoliosis

The human spinal column is a dynamic,segmented,bony,and cartilaginous structure that protects the neurologic system and simultaneously provides balance and flexibility.Children with developmental disorders that affect the patterning or shape of the spine can be at risk of neurologic and other physiologic dysfunctions.The most common developmental disorder of the spine is scoliosis,a lateral deformity in the shape of the spinal column.Scoliosis may be part of the clinical spectrum that is observed in many developmental disorders,but typically presents as an isolated symptom in otherwise healthy adolescent children.Adolescent idiopathic scoliosis(AIS)has defied understanding in part due to its genetic complexity.Breakthroughs have come from recent genome-wide association studies(GWAS)and next generation sequencing(NGS)of human AIS cohorts,as well as investigations of animal models.These studies have identified genetic associations with determinants of cartilage biogenesis and development of the intervertebral disc(IVD).Current evidence suggests that a fraction of AIS cases may arise from variation in factors involved in the structural integrity and homeostasis of the cartilaginous extracellular matrix(ECM).Here,we review the development of the spine and spinal cartilages,the composition of the cartilage ECM,the so-called"matrisome"and its functions,and the players involved in the genetic architecture of AIS.We also propose a molecular model by which the cartilage matrisome of the IVD contributes to AIS susceptibility.

Reliability and concurrent validity of postural asymmetry measurement in adolescent idiopathic scoliosis

AIM To investigate the reliability and concurrent validity of the Baseline~? Body Level/Scoliosis meter for adolescent idiopathic scoliosis postural assessment in three anatomical planes.METHODS This is an observational reliability and concurrent validity study of adolescent referrals to the Orthopaedic department for scoliosis screening at KarolinskaUniversity Hospital, Stockholm, Sweden between MarchMay 2012. A total of 31 adolescents with idiopathic scoliosis(13.6 ± 0.6 years old) of mild-moderate curvatures(25°± 12°) were consecutively recruited. Measurement of cervical, thoracic and lumbar curvatures, pelvic and shoulder tilt, and axial thoracic rotation(ATR) were performed by two trained physiotherapists in one day. The intraclass correlation coefficient(ICC) was used to determine the inter-examiner reliability(ICC2,1) and the intra-rater reliability(ICC3,3) of the Baseline~? Body Level/Scoliosis meter. Spearman's correlation analyses were used to estimate concurrent validity between the Baseline~? Body Level/Scoliosis meter and Gold Standard Cobb angles from radiographs and the Orthopaedic Systems Inc. Scoliometer.RESULTS There was excellent reliability between examiners for thoracic kyphosis(ICC2,1 = 0.94), ATR(ICC2,1 = 0.92) and lumbar lordosis(ICC2,1 = 0.79). There was adequate reliability between examiners for cervical lordosis(ICC2,1 = 0.51), however poor reliability for pelvic and shoulder tilt. Both devices were reproducible in the measurement of ATR when repeated by one examiner(ICC3,3 0.98-1.00). The device had a good correlation with the Scoliometer(rho = 0.78). When compared with Cobb angle from radiographs, there was a moderate correlation for ATR(rho = 0.627).CONCLUSION The Baseline~? Body Level/Scoliosis meter provides reliable transverse and sagittal cervical, thoracic and lumbar measurements and valid transverse plan measurements of mild-moderate scoliosis deformity.

Methylenetetrahydrofolate Reductase (MTHFR) Gene Mutations in Patients with Idiopathic Scoliosis: A Clinical Chart Review

The effects of genetic variations of methylenetetrahydrofolate reductase (MTHFR) enzyme activity have been the discussion of many research papers. It has been associated with multiple neurological sequelae, and has been implicated in other chronic diseases. Although many genetic influences on the development and/or progression of idiopathic scoliosis have been reported, there has been no report of any relationship between MTHFR mutations and idiopathic scoliosis. This paper compared two groups of patients who received MTHFR genetic testing. One group had a history of idiopathic scoliosis, while the other served as a control group. The scoliosis group showed a positive MTHFR mutation in 23 out of 44 patients, while the control group showed 11/44 (P < 0.01). Given the increased incidence of MTHFR defects in scoliosis patients, this study warrants further investigation into how MTHFR variations may trigger the development or progression of idiopathic scoliosis.

Application of Out-of-Hospital Extended Nursing in Brace Treatment of Patients with Idiopathic Scoliosis

Objective:To investigate the effect of out-of-hospital extended nursing on the compliance behaviors and therapeutic effect of brace treatment of patients with idiopathic scoliosis.Methods:54 patients with idiopathic scoliosis between February 2015 and December 2017 were randomly divided into control group and observation group.Patients in the control group received pelvic suspension traction,gymnastic exercises,and brace wear at discharge,on the basis of which patients in the observation group were added with extended care outside the hospital.The compliance behaviors and the changes of scoliosis angle(Cobb angle)of patients in the 2 groups were evaluated.Results:Compared with the control group,patients in the observation group had better compliance behaviors in completion status of functional exercise(χ2=5.594,P=0.018),brace wear(χ2=6.171,P=0.013),subsequent visit on time(χ2=9.247,P=0.002).Cobb angle was improved significantly in both groups at the last follow-up compared with that on admission,and the improvement was more significantly in the observation group(P<0.001).Conclusion:Through the implementation of out-of-hospital extended nursing,the compliance behaviors and clinical effect of brace treatment for idiopathic scoliosis patients are obviously improved,and this active nursing model is worth popularizing in clinic.

The Biomechanical Aetiology of the So-Called Idiopathic Scoliosis. The Role of Gait and Standing at “Ease” on the Right Leg in the Development of the Deformity

The article presents the biomechanical etiology of the so-called idiopathic scoliosis. The research was conducted in the years 1985-2013, but the importance of the observations connected with the so-called idiopathic scoliosis were completed in 2007 (4, 5, 6, 7, 8, 9). All types of spine deformity are proved to have a connection with gait and with standing “at ease” on the right leg. Every type of scoliosis begins to develop at the age of 2 - 3. The article provides short information about new screening tests and new exercises in the course of causal prophylaxis and treatment.

A Thermo-Mechanical Behavior Simulation of A NiTi Staple Used for the Correction of Idiopathic Scoliosis

In order to treat scoliosis, a thermo-mechanical behavior study of shape memory alloy bone staple has been proposed. A pre-stretched shape-memory-alloy bone staple, which has been heated above the transition temperature, provides greater compressive force upon insertion between two vertebrae and allows the control of idiopathic scoliosis development. Until now, the optimal design has not been reached due to the lack of appropriate design tools for shape memory alloy devices. In this paper, a shape memory alloy bone staple model is proposed by developing a user subroutine UMAT based on Boyd et al. unified thermodynamic shape memory alloy constitutive law using the finite element analysis software, ABAQUS. The numerical results for superelastic and shape memory effect under the tensile and three-point bending tests are presented. Simulations of the shape memory effects and force generation of the shape memory alloy staple are also shown.

Accuracy of pedicle screw placement in Lenke 1 adolescent idiopathic scoliosis surgery using intraoperative navigation with a simple calibration technique

Objective:To compare the position and the grade of screw perforation in Lenke 1 adolescent idiopathic scoliosis(AIS)surgery using intraoperative navigation system with and without calibration technique,and to explore the related factors of navigation deviation and the clinical significance of calibration technique.Methods:From 2014 to 2017,a total of 45 Lenke 1 AIS surgical cases were enrolled in this study.The 23 surgical cases were assisted with intraoperative navigation system(Navigation group)and another 22 cases received surgery using intraoperative navigation system with calibration technique(Calibration group).In two groups,the basic information and radiological data were all recorded.Postoperative CT scan with 3D reconstruction was used to analyze the accuracy of pedicle screw placement,as well as the length and position of cortical perforation.Results:There was no statistical difference between two groups in gender,age,Risser sign,both preoperative Cobb angles and flexibility of the major curve,as well as numbers of pedicle screws.477 and 469 pedicle screws were implanted in the navigation group and the calibration group respectively.The rate for major pedicle perforations 2 mm(grades 2,3)was 7.8%in navigation group.It was statistically significant difference from the 4.3%screw misplacement in calibration group(P=0.014).In navigation group,the rates of major pedicle perforations 2 mm were medial:3.4%,lateral:3.6%and anterior:0.6%respectively.The corresponding rates were 1.1%,2.6%and 0.4%in calibration group respectively.The rates of the medial cortical perforation 2 mm showed statistical difference between two groups(P=0.016).No serious complications,such as nerve or vascular injury,were found in all patients.Conclusion:Intraoperative navigation system with calibration technique provides the real-time monitoring of navigation deviation,the higher accuracy of pedicle screw insertion,the lower medial cortical perforation rate and the less complication rate,as well as a simple calibration technique with higher accuracy of screw placement in comparison to intraoperative navigation system for Lenke 1AIS surgery.

Catechol-O-Methyl Transferase (COMT) Enzyme Gene Variations in Patients with Idiopathic Scoliosis: A Clinical Chart Review

The effects of genomic variations and their associations with idiopathic scoliosis have been the discussion of many research trials. Previous investigations into catechol-o-methyl transferase (COMT) have identified its importance in dopamine and estrogen metabolism. While many genetic influences on idiopathic scoliosis have been observed, there has been no report of any relationship between COMT mutations and idiopathic scoliosis. The present study compared two groups of patients who received COMT genetic testing. The first group had a history of idiopathic scoliosis, while the other served as a non-scoliotic control group. The scoliosis group showed a positive COMT mutation in 33 out of 58 patients, while the control group showed 22/58 (P < 0.05). The homozygous genotype Met/Met occurred significantly more frequently in the scoliosis group. The increased incidence of COMT defects in the current scoliosis patient group warrants further study into how COMT variations may relate to the development or progression of idiopathic scoliosis.

Resolution of Amenorrhea and Chronic Constipation in an Adult Patient with Idiopathic Scoliosis Wearing a Scoliosis Activity Suit for 6 Months: A Case Report

Objective: To report the symptomatic and radiographic changes in an adult scoliosis patient with a history of amenorrhea and chronic constipation. Clinical Features: Patient presented for treatment with an 8-year history of amenorrhea and chronic constipation. Radiographic study showed a right thoracic/left lumbar double major scoliosis. Intervention and Outcome: Patient was fitted for a scoliosis activity suit and given instructions for continued home use, building up to 3 - 4 hours total daily. After 6 months of use, her amenorrhea and chronic constipation had resolved, and both scoliosis Cobb angles also improved. Scores on before and after SRS-22r questionnaires, as well as a quadruple numerical pain rating scale, also improved. Conclusion: A patient wearing a scoliosis activity suit for 6 months reported symptomatic changes as well as radiographic, pain, and quality of life improvements. The results of this case cannot be generalized. More investigation into the association of scoliosis and other organic symptoms is warranted.