scholarly journals Higher pedicle screw density does not improve curve correction in Lenke 2 adolescent idiopathic scoliosis

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Timothy J. Skalak ◽  
Joel Gagnier ◽  
Michelle S. Caird ◽  
Frances A. Farley ◽  
Ying Li
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Thoracic Kyphosis ◽  
Curve Correction ◽  
Major Curve ◽  
Curve Magnitude ◽  
Screw Density ◽  
Implant Density ◽  
Lenke 2

Abstract Purpose Higher pedicle screw density posterior spinal fusion (PSF) constructs have not been shown to result in improved curve correction in Lenke 1 and 5 adolescent idiopathic scoliosis (AIS) but do increase cost. The purpose of this study questioned whether higher screw density constructs improved curve correction and maintenance of correction in Lenke 2 AIS. Secondary goals were to identify predictive factors for correction and postoperative magnitude of curves in Lenke 2 AIS. Methods We identified patients 11 to 17 years old who underwent primary PSF for Lenke 2 AIS between 2007 and 2017 who had minimum follow-up of 2 years. Demographic and radiographic data were collected to perform regression and elimination analysis. Results Thirty patients (21 females, 9 males) were analyzed. Average age and SD at time of surgery was 14.0 ± 1.8 years (range, 11–17 years), and median follow-up was 2.8 years (IQR 2.1–4.0 years). Implant density did not predict final postoperative curve magnitude. Predictors of final postoperative curve magnitude were sex and preoperative curve magnitude. Predictors of percentage of correction of major curve were sex and age at the time of surgery. Predictors of final postoperative thoracic kyphosis were sex and percent flexibility preop. Females had lower final postoperative major curve magnitude, a higher percent curve correction, and lower postoperative thoracic kyphosis. Conclusions Increased implant density is not predictive of postoperative curve magnitude in Lenke 2 AIS. Predictors of postoperative curve magnitude are sex and preoperative curve magnitude. Level of evidence Level III, retrospective observational

scholarly journals “Higher Pedicle Screw Density Does Not Result in Improved Curve Correction in Lenke 2 Adolescent Idiopathic Scoliosis”

2021 ◽  
Author(s):  
Timothy Skalak ◽  
Joel Gagnier ◽  
Michelle S. Caird ◽  
Frances A. Farley ◽  
Ying Li
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Thoracic Kyphosis ◽  
Curve Correction ◽  
Major Curve ◽  
Curve Magnitude ◽  
Screw Density ◽  
Implant Density ◽  
Lenke 2

Abstract Purpose: Higher pedicle screw density posterior spinal fusion (PSF) constructs have not been shown to result in improved curve correction in Lenke 1 and 5 adolescent idiopathic scoliosis (AIS) but do increase cost. The purpose of this study questioned whether higher screw density constructs improved curve correction and maintenance of correction in Lenke 2 AIS. Secondary goals were to identify predictive factors for correction and postoperative magnitude of curves in Lenke 2 AIS. Methods: We identified patients 11 to 17 years old who underwent primary PSF for Lenke 2 AIS between 2007 and 2017 who had minimum follow up of 2 years. Demographic and radiographic data were collected to perform regression and elimination analysis. Results: Thirty patients (21 Female, 9 male) were analyzed. Average age and SD at time of surgery was 14.0 ± 1.8 years (range, 11-17 years) and median follow-up was 2.8 years (IQR 2.1-4.0 years). Implant density did not predict final postoperative curve magnitude. Predictors of final postoperative curve magnitude were sex and preoperative curve magnitude. Predictors of percentage of correction of major curve were sex and age at the time of surgery. Predictors of final postoperative thoracic kyphosis were sex and percent flexibility preop. Females had lower final postoperative major curve magnitude, a higher percent curve correction, and lower postoperative thoracic kyphosis.Conclusions: Increased implant density is not predictive of postoperative curve magnitude in Lenke 2 AIS. Predictors of postoperative curve magnitude are sex and preoperative curve magnitude.Level of Evidence: Level III Retrospective Observational

scholarly journals Predictability of Coronal Curve Flexibility in Postoperative Curve Correction in Adolescent Idiopathic Scoliosis: The Effect of the Sagittal Profile

2019 ◽  
Vol 10 (3) ◽  
pp. 303-311 ◽  
Author(s):  
Søren Ohrt-Nissen ◽  
Hideki Shigematsu ◽  
Jason Pui Yin Cheung ◽  
Keith D. K. Luk ◽  
Dino Samartzis
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Cobb Angle ◽  
Thoracic Kyphosis ◽  
Clinical Decision Making ◽  
Sagittal Profile ◽  
Curve Correction ◽  
Sagittal Vertical Axis ◽  
Flexibility Index

Study Design: Retrospective cohort study. Objectives: To assess how the thoracic kyphosis affects the ability of the fulcrum bending radiograph (FBR) to predict the coronal thoracic curve correction. Methods: A retrospective study of prospectively collected data was conducted of 107 consecutive patients with thoracic adolescent idiopathic scoliosis (AIS) treated with a standard screw-fixation protocol. Radiographic variables were assessed preoperatively and at 2-year follow-up. Curve flexibility was determined based on the FBR and the Fulcrum Bending Flexibility Index (FBCI). Radiographic variables included preoperative Cobb angle, T5-T12 kyphosis, T12-S1 lordosis, sagittal vertical axis, list, T1-T12 length, truncal shift, and radiographic shoulder height. Patients were also categorized as hypo-, normo-, or hyperkyphotic. Results: Based on multivariate modeling, an increase in FBR Cobb angle and thoracic kyphosis were significantly associated with an increase in FBCI (increased mismatch between the FBR and postoperative Cobb angles) at 2-year follow-up ( P < 0.001). In patients with hyperkyphosis, a longer instrumented length existed despite similar curve size and shorter curve length than the hypo- and normokyphotic groups. Based on these findings, we developed a new predictive postoperative curve correction index, known as the Multiprofile Flexibility Index (MFI). Conclusions: Our results show that an increase in preoperative thoracic kyphosis is associated with an increased difference between the preoperative coronal curve flexibility and the postoperative coronal curve correction. Our findings broaden the understanding of curve flexibility and indicate that selection of fusion levels may need to take into consideration the sagittal profile to improve clinical decision making and optimize outcome.

Influence of curve morphology and location on the efficacy of rigid conservative treatment in patients with adolescent idiopathic scoliosis

2021 ◽  
Vol 103-B (2) ◽  
pp. 373-381
Author(s):  
Patrick Strube ◽  
Maria Gunold ◽  
Tanja Müller ◽  
Mario Leimert ◽  
André Sachse ◽  
...  
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Conservative Treatment ◽  
Idiopathic Scoliosis ◽  
Treatment Failure ◽  
Univariate Analysis ◽  
Curve Progression ◽  
Curve Correction ◽  
Major Curve ◽  
Apical Rotation ◽  
Curve Magnitude

Aims The aim of the present study was to answer the question whether curve morphology and location have an influence on rigid conservative treatment in patients with adolescent idiopathic scoliosis (AIS). Methods We retrospectively analyzed AIS in 127 patients with single and double curves who had been treated with a Chêneau brace and physiotherapeutic specific exercises (B-PSE). The inclusion criteria were the presence of structural major curves ≥ 20° and < 50° (Risser stage 0 to 2) at the time when B-PSE was initiated. The patients were divided into two groups according to the outcome of treatment: failure (curve progression to ≥ 45° or surgery) and success (curve progression < 45° and no surgery). The main curve type (MCT), curve magnitude, and length (overall, above and below the apex), apical rotation, initial curve correction, flexibility, and derotation by the brace were compared between the two groups. Results In univariate analysis treatment failure depended significantly on: 1) MCT (p = 0.008); 2) the apical rotation of the major curve before (p = 0.007) and during brace treatment (p < 0.001); 3) the initial and in-brace Cobb angles of the major (p = 0.001 and p < 0.001, respectively) and minor curves (p = 0.015 and p = 0.002); 4) major curve flexibility (p = 0.005) and the in-brace curve correction rates (major p = 0.008, minor p = 0.034); and 5) the length of the major curve (LoC) above (p < 0.001) and below (p = 0.002) the apex. Furthermore, MCT (p = 0.043, p = 0.129, and p = 0.017 in MCT comparisons), LoC (upper length p = 0.003, lower length p = 0.005), and in-brace Cobb angles (major p = 0.002, minor p = 0.027) were significant in binary logistic regression analysis. Conclusion Curve size, location, and morphology were found to influence the outcome of rigid conservative treatment of AIS. These findings may improve future brace design and patient selection for conservative treatment. Cite this article: Bone Joint J 2021;103-B(2):373–381.

scholarly journals Low-Density Pedicle Screw Constructs for Adolescent Idiopathic Scoliosis: Evaluation of Effectiveness and Cost

2017 ◽  
Vol 8 (2) ◽  
pp. 114-120 ◽  
Author(s):  
Oliver O. Tannous ◽  
Kelly E. Banagan ◽  
Eric J. Belin ◽  
Ehsan Jazini ◽  
Tristan B. Weir ◽  
...  
Keyword(s):  
Idiopathic Scoliosis ◽  
Thoracic Kyphosis ◽  
Lower Cost ◽  
Low Density ◽  
Lumbar Curve ◽  
Radiographic Assessment ◽  
Curve Correction ◽  
Lowest Instrumented Vertebra ◽  
Screw Density

Study Design: Retrospective cohort study. Objective: To determine whether a low-density (LD) screw construct can achieve curve correction similar to a high-density (HD) construct in adolescent scoliosis. Methods: Patients treated operatively for idiopathic scoliosis between 2007 and 2011 were identified through a database review. A consistent LD screw construct was used. Radiographic assessment included percent correction of major and fractional lumbar curves, T5-T12 kyphosis, and angle of lowest instrumented vertebra (LIV). Costs were compared with HD constructs. Results: Thirty-five patients were included in the analysis. Ages ranged from 12 to 19 years (mean = 14.9 years). Average screw density was 1.2 screws per level (range = 1.07-1.5 screws). Mean percent curve correction at latest follow-up: major curve, 66.9%; fractional lumbar curve, 63%. Average postoperative thoracic kyphosis: 29.5°. Mean LIV angle: 5.6°. Average construct cost was $14 871 per case compared with $23 840 per case if all levels had been instrumented with 2 screws, amounting to an average savings of $9000. Conclusions: Our LD screw construct is among the lowest density constructs reported and achieves curve correction comparable to HD constructs at substantially lower cost.

scholarly journals Surgical management of moderate adolescent idiopathic scoliosis with a fusionless posterior dynamic deformity correction device: interim results with bridging 5–6 disc levels at 2 or more years of follow-up

2020 ◽  
Vol 32 (5) ◽  
pp. 748-754 ◽  
Author(s):  
Yizhar Floman ◽  
Ron El-Hawary ◽  
Michael A. Millgram ◽  
Baron S. Lonner ◽  
Randal R. Betz
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Deformity Correction ◽  
Successful Outcome ◽  
Inclusion Criteria ◽  
Major Curve ◽  
Curve Magnitude ◽  
The Mean

OBJECTIVEA posterior dynamic deformity correction (PDDC) system was used to correct adolescent idiopathic scoliosis (AIS) without fusion. The preliminary outcomes of bridging only 3–4 discs in patients with variable curve severity have previously been reported. This paper examines a subgroup of patients with the authors’ proposed current indications for this device who were also treated with a longer construct.METHODSInclusion criteria included a single AIS structural curve between 40° and 60°, curve flexibility ≤ 30°, PDDC spanning 5–6 levels, and minimum 2-year follow-up. A retrospective review was conducted and demographic and radiographic data were recorded. A successful outcome was defined as a curve magnitude of ≤ 30° at final follow-up. Any serious adverse events and reoperations were recorded.RESULTSTwenty-two patients who met the inclusion criteria were operated on with the PDDC in 5 medical centers. There were 19 girls and 3 boys, aged 13–17 years, with Risser grades ≥ 2. Thirteen had Lenke type 1 curves and 9 had type 5 curves. The mean preoperative curve was 47° (range 40°–55°). At a minimum of 2 years’ follow-up, the mean major curve measured 25° (46% correction, p < 0.05). In 18 (82%) of 22 patients, the mean final Cobb angle measured ≤ 30° (range 15°–30°). Trunk shift was corrected by 1.5 cm (range 0.4–4.3 cm). The mean minor curve was reduced from 27° to 17° at final follow-up (35% correction, p < 0.05). For Lenke type 1 patterns, the mean 2D thoracic kyphosis was 24° preoperatively versus 27° at final follow-up (p < 0.05), and for Lenke type 5 curves, mean lumbar lordosis was 47° preoperatively versus 42° at final follow-up (p < 0.05). The mean preoperative Scoliosis Research Society-22 questionnaire score improved from 2.74 ± 0.3 at baseline to 4.31 ± 0.4 at 2 years after surgery (p < 0.0001). The mean preoperative self-image score and satisfaction scores improved from preoperative values, while other domain scores did not change significantly. Four patients (18%) underwent revision surgery because of nut loosening (n = 2), pedicle screw backup (n = 1), and ratchet malfunction (n = 1).CONCLUSIONSIn AIS patients with a single flexible major curve up to 60°, the fusionless PDDC device achieved a satisfactory result as 82% had residual curves ≤ 30°. These findings suggest that the PDDC device may serve as an alternative to spinal fusion in select patients.

Does Higher Screw Density Result in Increased Curve Correction and Improved Clinical Outcomes in Adolescent Idiopathic Scoliosis (AIS)

2012 ◽  
Vol 12 (9) ◽  
pp. S129 ◽  
Author(s):  
A. Noelle Larson ◽  
David W. Polly ◽  
Beverly E. Diamond ◽  
T. Ledonio Charles Gerald ◽  
Daniel J. Sucato ◽  
...  
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Clinical Outcomes ◽  
Curve Correction ◽  
Density Result ◽  
Screw Density

scholarly journals ADOLESCENT IDIOPATHIC SCOLIOSIS: EVALUATION ON THE EFFECT OF SCREW DENSITY IN THE CORRECTION

2016 ◽  
Vol 15 (1) ◽  
pp. 17-21
Author(s):  
Enguer Beraldo Garcia ◽  
Liliane Faria Garcia ◽  
Enguer Beraldo Garcia Jr ◽  
Roberto Garcia Gonçalves ◽  
Saulo Terror Giesbrecht ◽  
...  
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Medical Records ◽  
Transpedicular Fixation ◽  
Correction Rate ◽  
Screw Density ◽  
The Difference ◽  
Implant Density ◽  
Biostatistical Analysis ◽  
Main Curve

ABSTRACT Objective: The objective was to investigate implant density or the number of screws correlated with the correction of the main curve in patients undergoing surgery for adolescent idiopathic scoliosis (AIS). Methods: We evaluated 112 medical records: 33 patients with screw density of up to 50%, and 79 patients with a density of 100%; all patients underwent surgical correction by posterior approach with transpedicular fixation. Results: In the group of patients with screw density of up to 50% the residual Cobb median was 10°; in the group with 100% density, the median was 7°. Conclusion: Biostatistical analysis showed that the group with up to 50% of screw density presented correction rate of 82.1% and the group with 100% density had correction of about 86.8%. It is therefore concluded that the difference is statistically significant in favor of the fixation with 100% density (p =0.010).

scholarly journals Selective thoracolumbar/lumbar fusion for Syringomyelia-associated scoliosis: a case-control study with Lenke 5C adolescent idiopathic scoliosis

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Fan Feng ◽  
Hongxing Shen ◽  
Xiuyuan Chen ◽  
Zude Liu ◽  
Jianwei Chen ◽  
...  
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Thoracic Kyphosis ◽  
Case Control Study ◽  
Lumbar Fusion ◽  
Neurological Deficits ◽  
Control Group ◽  
Control Study

Abstract Background Selective thoracolumbar/lumbar fusion technique was introduced to treat adolescent idiopathic scoliosis (AIS) patients with major thoracolumbar/lumbar curves. Theoretically, this surgical strategy could also be applied to syringomyelia patients. No previous study has specifically addressed the effectiveness of selective thoracolumbar/lumbar fusion for patients with syringomyelia-associated scoliosis. The aim of the study was to investigate the effectiveness of selective thoracolumbar/lumbar fusion for the surgical treatment of patients with syringomyelia-associated scoliosis. Methods From February 2010 to September 2016, 14 syringomyelia-associated patients with major thoracolumbar/lumbar curves were retrospectively reviewed. Besides, 30 Lenke 5C AIS patients were enrolled as a control group. Posterior selective thoracolumbar/lumbar fusion was performed for both groups. Patients’ demographic, operative, radiological, and quality of life data were reviewed with follow-up. Intragroup comparisons were performed for each parameter. Results The two groups were matched by age, gender, curve characteristics, duration of follow-up, and all preoperative radiographic parameters except for thoracic kyphosis. After surgery, the average correction rate of the major thoracolumbar/lumbar curve was 82.2 ± 7.8% in the syringomyelia group, which was not significantly different from that of AIS group (82.5 ± 10.6%, P = 0.47). A similar improvement of unfused thoracic curve was observed between the two groups (50.1 ± 16.5% vs. 48.5 ± 26.9%, P = 0.29). During the follow-up, the correction effect of scoliosis was well maintained, without aggravation of the original neural symptoms or fresh permanent neurological deficits. Of note, the number of fusion levels was significantly larger in syringomyelia group than that in AIS group (7.6 ± 1.4 vs. 6.5 ± 1.2, P < 0.01). The average follow up was 47.6 months (36–81 months). Conclusion Similar to AIS cases, syringomyelia-associated scoliosis can be effectively and safely corrected by selective thoracolumbar/lumbar fusion with satisfactory surgical outcomes. However, the syringomyelia group, on average, required an additional fused segment for treatment as compared to the AIS group (7.6 versus 6.5 in the AIS group).

Efficacy of Routine Intraoperative Cranio-Femoral Traction in Surgical Treatment of Adolescent Idiopathic Scoliosis Curves Measuring Between 50° and 90°

2021 ◽  
pp. 219256822110529
Author(s):  
Jacob R. Carl ◽  
Gurpal Pannu ◽  
Evan Cherng-Yeh Chua ◽  
Adam Bacon ◽  
Blythe Durbin-Johnson ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Adolescent Idiopathic Scoliosis ◽  
Blood Loss ◽  
Idiopathic Scoliosis ◽  
Revision Surgery ◽  
Operative Time ◽  
Curve Correction ◽  
Major Curve ◽  
Estimated Blood Loss ◽  
Retrospective Comparative Study

Study Design Retrospective Comparative Study, Level III. Objective In patients with scoliosis >90°, cranio-femoral traction (CFT) has been shown to obtain comparable curve correction with decreased operative time and blood loss. Routine intraoperative CFT use in the treatment of AIS <90° has not been established definitively. This study investigates the effectiveness of intraoperative CFT in the treatment of AIS between 50° and 90°, comparing the magnitude of curve correction, blood loss, operative time, and traction-related complications with and without CFT. Methods 73 patients with curves less than 90° were identified, 36 without and 37 with cranio-femoral traction. Neuromuscular scoliosis and revision surgery were excluded. Age, preoperative Cobb angles, bending angles, and curve types were recorded. Surgical characteristics were analyzed including number of levels fused, estimated blood loss, operative time, major curve correction (%), and degree of postoperative kyphosis. Results Patients with traction had significantly higher preoperative major curves but no difference in age or flexibility. Lenke 1 curves had significantly shorter operative time and improvement in curve correction with traction. Among subjects with 5 to 8 levels fused, subjects with traction had significantly less EBL. Operative time was significantly shorter for subjects with 5-8 levels and 9-11 levels fused. Curves measuring 50°-75° showed improved correction with traction. Conclusion Intraoperative traction resulted in shorter intraoperative time and greater correction of major curves during surgical treatment of adolescent idiopathic scoliosis less than 90°. Strong considerations should be given to use of intraoperative CFT for moderate AIS.

scholarly journals The correlations between the anchor density and the curve correction of adolescent idiopathic scoliosis surgery

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Yu-Cheng Yeh ◽  
Chi-Chien Niu ◽  
Lih-Huei Chen ◽  
Wen-Jer Chen ◽  
Po-Liang Lai
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Thoracic Kyphosis ◽  
Three Dimensional ◽  
High Density ◽  
Scoliosis Surgery ◽  
Low Density ◽  
Curve Correction ◽  
Kyphosis Correction ◽  
Positive Correlations

Abstract Background The optimal anchor density in adolescent idiopathic scoliosis (AIS) surgery to achieve good curve correction remains unclear. The purpose of the study is to analyze the correlations between three-dimensional curve correction and anchor density in the pedicle screw-based posterior fusion of AIS. Methods One hundred and twenty-seven AIS patients receiving primary posterior fusion with pedicle screw instrumentation were retrospectively reviewed. Anchor density (AD) was defined as the screws number per fused spinal segment. The correlations between three-dimensional curve correction radiographic parameters and anchor density were analyzed with subgroup analysis based on different curve types, curve magnitudes, and curve flexibilities. The differences of curve correction parameters between the low-density (AD ≤1.4), middle-density (1.4 < AD ≤1.7) and high-density (AD > 1.7) groups were also calculated. Independent t-test, analysis of variance (ANOVA), and Pearson’s correlation coefficient were used for statistical analysis. Results There were no correlations between the anchor density and the coronal curve correction or apical vertebral rotation (AVR) correction. In the sagittal plane, mild positive correlations existed between anchor density and thoracic kyphosis correction in all patients (r = 0.27, p = 0.002). Subgroup analysis revealed similar mild positive correlations in Lenke 1 (r = 0.31, p = 0.02), Lenke 1–3 (r = 0.27, p = 0.01), small curves (40°-60°, r = 0.38, p <  0.001), and flexible curves (flexibility > 40%, r = 0.34, p = 0.01). There were no differences between low-density (mean 1.31), middle-density (mean 1.55), and high-density (mean 1.83) in terms of coronal or axial curve correction parameters. Low-density group has longer fused level (mean difference 2.14, p = 0.001) and smaller thoracic kyphosis correction (mean difference 9.25°, p = 0.004) than high-density group. Conclusion In our study, the anchor density was not related to coronal or axial curve corrections. Mild positive correlations with anchor density were found in thoracic kyphosis correction, especially in patients with smaller and flexible curves. Low anchor density with longer fusion level achieves similar curve corrections with middle or high anchor density in adolescent idiopathic scoliosis surgery.

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