Axial Vertebral Rotation Research Articles

Using ultrasound reflection coefficient index and other clinical parameters to predict the risk of progression in adolescents with idiopathic scoliosis (AIS)- a pilot study.

To determine the association of the ultrasound reflection coefficient index and other clinical parameters to predict curve progression in children with AIS. Sixty-six females (13.9 ± 1.5 years old) under observation with baseline Cobb angle (24.4 ± 10.4°) consented and participated. Besides the standard clinical procedures, all participants were scanned by an ultrasound (US) imager in a standing position. All participants had been followed, and the average follow-up visit was 7.5 ± 3.1 months. Five parameters were investigated, including the Cobb angle and the Risser sign measured from the radiographs, and the kyphotic angle (KA), the axial vertebral rotation (AVR), and the reflection coefficient (RC) index measured from the ultrasonographs. The curve was considered progressed when the Cobb angle measured on two consecutive radiographs was increased by more than 5°. Among the 5 parameters, the KA, RC index, and Risser sign were found to be significantly associated with progression (p < 0.05). Children who had KA ≤ 38° and RC ≤ 0.06 showed higher chances of progression (62%) versus children with KA > 38° and RC > 0.06. This pilot study showed that curve progression is associated with the Risser sign, KA, and RC index. Other parameters and a more extensive clinical study should be combined to develop a higher-accuracy prediction model.

The effect of arm positions used during radiography on spinal alignment parameters assessed by 3D ultrasound imaging in adolescents with and volunteers without idiopathic scoliosis.

Clinicians monitor scoliosis progression using multiple radiographs during growth. During imaging, arms must be elevated to visualize vertebrae, possibly affecting sagittal alignment. This study aimed to determine the arm position that best represents habitual standing (and possibly allowing hand-based skeletal maturity assessment) to obtain frontal and lateral stereo-radiographs as measured using frontal, sagittal, and transverse angles. Females with and without, and males with Adolescent Idiopathic Scoliosis (AIS) were recruited consecutively. Patients were scanned using 3D Ultrasound imaging (3DUS), in 10 arm positions; habitual standing, arms supported anteriorly at 60° flexion, fingers to clavicle, chin, zygomatic, and eyebrows, arms abducted 90°, hands on wall, on blocks, and unsupported. Axial vertebral rotation (AVR) differences, frontal, and sagittal curve angles were measured. Repeated measures ANOVAs with Sidak post-hoc tests compared positions. Ninety females with and without AIS with mean age, and height of 17 ± 4years, and 162 ± 6cm, and ten males with AIS of 16 ± 3years, and 174 ± 11cm, respectively, were included. Female AIS single-curve showed larger curves in standing in all positions excluding hands on blocks (p > 0.05). Sagittal parameters showed decreases in kyphosis in arms abducted 90° and increases in lordosis in fingers to cheeks/eyebrows (p > 0.05). AVR twist was not significantly affected by position. Male AIS showed comparable results to females, but no significant differences weredetected. No position represented habitual standing for all groups. When arms are raised, decreases in curve angle were shown in single-curve patients, kyphosis decreased, and lordosis increased in all groups. Most accurate positioning for all parameters was in fingers to clavicle/chin position.

Comparison of en-bloc direct vertebrae rotation and non-direct vertebrae rotation for the correction of adolescent idiopathic scoliosis Lenke 5C: a retrospective study in Changsha, China.

A retrospective study. This study aimed to compare the clinical effectiveness of en-bloc direct vertebrae rotation (DVR) to non-DVR for the correction of Lenke 5C. The primary goal of posterior correction is to preserve the lumbar spine and achieve a well-balanced spine. However, very few studies have examined the effects of en-bloc DVR (ED) on Lenke 5C correction. A retrospective study was conducted with a minimum follow-up of four years involving 95 patients (ED group, n=45; non-DVR [ND] group, n=50). Radiographic measurements included thoracic kyphosis, lumbar lordosis, sagittal vertical axis, coronal balance, and Cobb angles preoperatively and postoperatively. Flexibility curves and axial vertebral rotation were assessed using computed tomography before and after surgery. Clinical outcomes were evaluated using the Scoliosis Research Society-22 (SRS-22) questionnaire. The preoperative major Cobb angles were comparable between the ED group (52.2°±2°) and the ND group (52.8°±3°), with no significant difference (p=0.327). At the last follow-up, the average Cobb angle was significantly lower in the ED group (4.6°±2°) compared to the ND group (6.1°±3°), indicating a significant difference (p=0.005). The postoperative radiographic shoulder height showed no significant difference at the last follow-up. The axial vertebral rotation was significantly greater in the ED group (8.4°±0°) than in the ND group (11.1°±1°) (p=0.001). Additionally, the ED group demonstrated substantial preservation of fusion levels with an average of 5.6 fused segments compared to 6.3 in the ND group. A significantly higher incidence of satisfactory outcomes was observed at the final follow-up, with the correction rate of the ED group superior to that of the ND group for adolescent idiopathic scoliosis Lenke 5C. Moreover, patients in the ED group reported better outcomes on the SRS-22 questionnaire and had a shorter hospital stay than those in the ND group.

Surface vs. skeleton: the relationship between surface topographic and radiographic measurements of shoulder symmetry in patients with scoliosis.

This study evaluates the relationship between existing radiographic measurements of shoulder asymmetry with novel surface topographic (ST) measurements, hypothesizing that these relationships will be weak. Data were gathered from a prospectively collected registry of patients who underwent ST scanning at a single tertiary care institution. Inclusion criteria were diagnosis of juvenile or adolescent idiopathic scoliosis, age 11-21, same-day ST and EOS radiographic evaluation. Twelve radiographic variables that evaluate shoulder height were measured, as well as curve magnitudes and vertebral axial rotation. ST data were collected using the 3dMDbody scanning system. Three ST measurements of shoulder symmetry were evaluated: ST-based AC angle (the angle between a line made between the surface of the AC joints and a line parallel to the ground), Shoulder Normal Asymmetry angle (the angle between the mirrored normals to the planes defined by the jugular notch, vertebral prominence, and AC joint), and Shoulder Volume Asymmetry Index (difference in volumes between the right and left shoulder). Univariate, followed by a stepwise multivariate linear regression was performed to evaluate the correlations of the radiographic measurements to the ST-based measurements. Correlation categories: weak (x < 0.4), moderate (0.4 ≤ x < 0.6), strong (0.6 ≤ x < 0.8), and very strong (x ≥ 0.8). 141 patients with idiopathic scoliosis were evaluated (65.2% female, mean age 15.1years, mean BMI 20.5kg/m2, with mean maximum curve 44.7 degrees). ST-based AC angle had moderate-to-strong correlations with several radiographic measurements, while ST-based Shoulder Normal Asymmetry angle and Shoulder Volume Asymmetry Index had weak or no correlation with individual radiographic measures. Multivariate models created using a combination of radiographic variables demonstrated a strongly positive correlation between radiographic variables and ST-based AC angle (R = 0.678) and moderately positive correlations with ST-based Shoulder Normal Asymmetry Angle (R = 0.488), and ST-based Shoulder Volume Asymmetry Index (R = 0.514). Radiographic measurements may be acceptable stand-ins for two-dimensional ST measurements such as AC angle, but not for more complex shoulder measurements based on three dimensions. This study demonstrates the inadequacy with which radiographic assessments evaluate shoulder height asymmetry and highlights the use of ST measurements.

Reliability and accuracy of scoliotic parameters on using a wireless handheld 3D ultrasound for children with adolescent idiopathic scoliosis: a pilot study.

To report the accuracy and reliability of Cobb angle (CA), axial vertebral rotation (AVR), kyphotic and lordotic angles (KA and LA) measurements on using a new 3D ultrasound (US) system. Forty participants (34F, 6M, aged 14.0 ± 2.3 years) were recruited. The first 20 participants were scanned by the validated US system and the new US system. The other 20 participants were scanned with the new US system only. Two raters (R1 and R2) performed the measurements: R1 has 10 years of experience in radiology but is new in ultrasound scoliosis, while R2 has 30 years of scoliosis experience. All US images were measured twice by R1, and once by R2. Forty posteroanterior and 30 lateral standing radiographs were obtained and measured once by R1. Statistical analysis consisted of mean absolute difference (MAD), intraclass correlation coefficient (ICC(2,1)), and Bland-Altman plots. R1 showed excellent intra-rater and inter-rater reliability for US measurements with ICCs(2,1) ≥ 0.91. The inter-method reliability was good between the two US systems for all parameters with ICCs(2,1) ≥ 0.85 and maximum MAD of 3.4°. The new US showed good reliability and accuracy compared to radiographs for CA, AVR and KA with ICCs(2,1) ≥ 0.81 and maximum MAD of 5.8°, but poor results for LA with ICCs(2,1) of 0.27-0.35 and MADs of 14.0°-15.4°. The new 3D US system showed good reliability and accuracy for CA, AVR and KA measurements, but a large measurement discrepancy on LA. A new measurement method for US LA may need to investigate.

Segmental deformity markers offer novel indicators of deformity progression risk in deformity-matched adolescent idiopathic scoliosis patients.

Identification of adolescent idiopathic scoliosis (AIS) patients with mild curvatures who pose significant risk of progressing to severe levels of curvatures is of paramount importance for clinical care. This study aimed to compare segmental deformity changes in AIS sub-cohorts that are dichotomised by progression status. Thirty-six female participants with Lenke 1 AIS curves were investigated with sequential MRIs during growth. Scans were reformatted to measure orthogonal segmental parameters, including sagittal/coronal wedging angles and axial rotation angles. Participants were dichotomised by progression. Two-tailed, independent sample t-tests were used to compare sub-cohort multi-segmental and segmental deformity parameters. Measurements were compared at each scan number and variable rates of change were determined using actual time between measures. AIS progression status sub-cohorts were comparable at scan 1 for multi-segmental deformity parameters (e.g. major thoracic curve angle, rib hump, kyphosis) (P > 0.05). However, apical measures of coronal IVD wedging, axial IVD rotation and axial vertebral rotation were segmental parameters at scan 1 which were larger for participants whose AIS would later go on to clinically progress (all P < 0.05). Measures of segmental hypokyphosis were comparable between groups. As development was tracked at each subsequent scan, coronal and axial plane differences between groups increased in both magnitude and number of differences. Initial disparity and then subsequent increasing magnitude of change of axial rotation may indicate a higher propensity to clinically progress in the future. This knowledge hopes to provide useful management information for AIS care providers and prognostic education for patients alike. II.

Validity of a fast automated 3d spine reconstruction measurements for biplanar radiographs: SOSORT 2024 award winner.

To validate a fast 3D biplanar spinal radiograph reconstruction method with automatic extract curvature parameters using artificial intelligence (AI). Three-hundred eighty paired, posteroanterior and lateral, radiographs from the EOS X-ray system of children with adolescent idiopathic scoliosis were randomly selected from the database. For the AI model development, 304 paired images were used for training; 76 pairs were employed for testing. The validation was evaluated by comparing curvature parameters, including Cobb angles (CA), apical axial vertebral rotation (AVR), kyphotic angle (T1-T12 KA), and lordotic angle (L1-L5 LA), to manual measurements from a rater with 8years of scoliosis experience. The mean absolute differences ± standard deviation (MAD ± SD), the percentage of measurements within the clinically acceptable errors, the standard error of measurement (SEM), and the inter-method intraclass correlation coefficient ICC[2,1] were calculated. The average reconstruction speed of the 76 test images was recorded. Among the 76 test images, 134 and 128 CA were exported automatically and measured manually, respectively. The MAD ± SD for CA, AVR at apex, KA, and LA were 3.3° ± 3.5°, 1.5° ± 1.5°, 3.3° ± 2.6° and 3.5° ± 2.5°, respectively, and 98% of these measurements were within the clinical acceptance errors. The SEMs and the ICC[2,1] for the compared parameters were all less than 0.7° and > 0.94, respectively. The average time to display the 3D spine and report the measurements was 5.2 ± 1.3s. The developed AI algorithm could reconstruct a 3D scoliotic spine within 6s, and the automatic curvature parameters were accurately and reliably extracted from the reconstructed images.

Inter-Evaluator Reliability of Sagittal and Rotational Spinal Measurements from 3D Ultrasound Imaging of Healthy Females in Standing with Varying Arm Positions

ABSTRACT Spinal alignment can be assessed without radiation using three-dimensional ultrasound imaging (3DUS). Reliable measurements could inform the ideal arm position for scoliosis radiographs. This study determined the inter-evaluator reliability of axial vertebral rotation (AVR) measurements and sagittal curve angles in healthy females from 3DUS spinal images in standing with two common radiograph arm positions: Chin and abduction (Abd). Three novice evaluators (R1, R2, and R3) measured images once. The Bland–Altman bias and limits of agreement (LOA) were calculated. T5-T12 kyphosis measurements met our bias and LOA error threshold only for R1 vs R2 in the Chin position [−0.53° (−10.7,9.7)]. The distance between the bias and the LOA also met our acceptable threshold of 5° for all mean AVRTwist, and all but one AVRTwist measurements (R1-R2_Chin = 5.9°). Three lordosis measurements did not meet our acceptable threshold (R1-R2_Chin, R1-R3_Chin, and R2-R3_Abd). The inter-evaluator reliability of novice evaluators was adequate and did not differ significantly between positions.

The Longitudinal Effects of Posterior Spinal Fusion with Derotation on Axial Deformity in Adolescent Idiopathic Scoliosis.

Retrospective case series. To characterize the change in angle of trunk rotation (ATR), axial vertebral rotation (AVR), and body surface rotation (BSR) in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with en-bloc derotation across multiple postoperative visits. Previous research has documented ATR, AVR, and BSR correction for AIS patients after surgery. However, there is a lack of evidence on the sustainability of this correction over time. This was a retrospective study from a single-center prospective surface topographic registry of patients with AIS, age 11-20 at time of surgery, who underwent PSF with en-bloc derotation. Patients with previous spine surgery were excluded. ATR was measured with a scoliometer, AVR through EOS radiographic imaging, and BSR via surface topographic scanning, Data collection occurred at: preoperative, six-week, three-month, six-month, one-year, and two-year postoperative visits. BSR and AVR were tracked at the preoperative apical vertebral level, and the level with maximum deformity, at each respective timepoint. Generalized estimating equations models were used for statistical analysis. Covariates included age, sex, and body mass index. 49 patients (73.4% female, mean age 14.6±2.2 years, mean preoperative coronal curve angle 57.9°±8.5, and 67% major thoracic) were evaluated. ATR correction was significantly improved at all postoperative timepoints and there was no significant loss of correction. AVR Max and AVR Apex were significantly improved at all timepoints but there was a significant loss of correction for AVR Apex between the six-week and one-year visit (P=0.032). BSR Max achieved significant improvement at the three-month visit. BSR Apex was significantly improved at the three-month and one-year visit. ATR and AVR demonstrated significant axial plane correction at two-years postoperative in patients undergoing PSF for AIS. BSR did not maintain significant improvement by the two-year visit.

Improvement in axial rotation with bracing reduces the risk of curve progression in patients with adolescent idiopathic scoliosis.

New evidence highlights the significance of 3D in-brace correction for Adolescent Idiopathic Scoliosis (AIS) patients. This study explores how axial parameters relate to treatment failure in braced AIS patients. AIS patients (Sanders 1-5) undergoing Rigo-Chêneau bracing at a single institution were included. Axial vertebral rotation (AVR) was determined by utilizing pre-brace and in-brace 3D reconstructions from EOS® radiographs. The primary outcome was treatment failure: surgery or coronal curve progression > 5°. Minimum follow-up was two years. 75 patients (81% female) were included. Mean age at bracing initiation was 12.8 ± 1.3years and patients had a pre-brace major curve of 31.0° ± 6.5°. 25 patients (76% female) experienced curve progression > 5°, and 18/25 required surgical intervention. The treatment failure group had larger in-brace AVR than the success group (5.8° ± 4.1° vs. 9.9° ± 7.6°, p = 0.003), but also larger initial coronal curve measures. In-brace AVR did not appear to be associated with treatment failure after adjusting for the pre-brace major curve (Hazard Ratio (HR):0.99, 95% Confidence Interval (CI):0.94-1.05, p = 0.833). Adjusting for pre-brace major curve, patients with AVR improvement with bracing had an 85% risk reduction in treatment failure versus those without (HR:0.15, 95% CI:0.02-1.13, p = 0.066). At the final follow-up, 42/50 (84%) patients without progression had Sanders ≥ 7. While in-brace rotation was not an independent predictor of curve progression (due to its correlation with curve magnitude), improved AVR with bracing was a significant predictor of curve progression. This study is the first step toward investigating the interplay between 3D parameters, skeletal maturity, compliance, and brace efficacy, allowing a future prospective multicenter study. Retrospective study; Level III.

Prevalence, distribution characteristic and risk factors of lumbar vertebral axial rotation in patients with lumbar disc herniation: a retrospective study

This retrospective study aimed to investigate the impact of lumbar disc herniation (LDH) on vertebral axial rotation (VAR) in the lumbar spine, focusing on both close and distant neighboring vertebrae. A total of 516 patients with LDH and an equal number of healthy individuals were included in the study, matched for age and gender. The degree of axial rotation for each lumbar spine vertebra was assessed using the Nash–Moe index. The results revealed that the prevalence of VAR in the lumbar spine was significantly higher in the LDH group compared to the Control group (65.7% vs 46.7%, P < 0.001). Among the LDH group, the L2 vertebra had the highest frequency of VAR (49.5%), followed by L1 (45.1%), and then L3 to L5 (33.6%, 8.9%, 3.1%, respectively). A similar pattern was observed in the Control group (L2, 39.8%; L1, 34.6%; L3, 23.2%; L4, 3.1%; L5, 0.8%). Furthermore, the study found that disc herniation was associated with a higher incidence of VAR not only in close neighboring vertebrae but also in distant neighboring vertebrae. This indicates that the biomechanical influence of LDH extends beyond just the immediate adjacent vertebrae. To identify potential risk factors for VAR in LDH patients, multivariate analysis was performed. The results revealed that age was an independent risk factor for VAR (OR 1.022, 95% CI [1.011, 1.034], P < 0.001). However, the duration of symptoms and presence of back pain were not found to be significant risk factors for VAR.

Correlation of transverse rotation of the spine using surface topography and 3D reconstructive radiography in children with idiopathic scoliosis.

The relationship between axial surface rotation (ASR) measured by surface topography (ST) and axial vertebral rotation (AVR) measured by radiography in the transverse plane is not well defined. This study aimed to: (1) quantify ASR and AVR patterns and their magnitudes from T1 to L5; (2) determine the correlation or agreement between the ASR and AVR; and (3) investigate the relationship between axial rotation differences (ASR-AVR) and major Cobb angle. This is a retrospective study evaluating patients (age 8-18) with IS or spinal asymmetry with both radiographic and ST measurements. Demographics, descriptive analysis, and correlations and agreements between ASR and AVR were evaluated. A piecewise linear regression model was further created to relate rotational differences to Cobb angle. Fifty-two subjects met inclusion criteria. Mean age was 14.1 ± 1.7 and 39 (75%) were female. Looking at patterns, AVR had maximal rotation at T8, while ASR had maximal rotation at T11 (r = 0.35, P = .006). Cobb angle was 24.1° ± 13.3° with AVR of - 1° ± 4.6° and scoliotic angle was 20.9° ± 11.5° with ASR of -2.3° ± 6.6°. (ASR-AVR) vs Cobb angle was found to be very weakly correlated with a curve of less than 38.8° (r = 0.15, P = .001). Our preliminary findings support that ASR measured by ST has a weak correlation with estimation of AVR by 3D radiographic reconstruction. This correlation may further help us to understand the application of transverse rotation in some clinical scenarios such as specific casting manipulation, padding mechanism in brace, and surgical correction of rib deformity.

Automatic axial vertebral rotation estimation on radiographs for adolescent idiopathic scoliosis by deep learning

PurposeAdolescent idiopathic scoliosis (AIS) is a three-dimensional spine deformity governed by lateral curvature and axial vertebral rotation (AVR). Estimating AVR is important for treatment decisions and the prediction of AIS progression. However, manual AVR measurements have intra-observer and inter-observer errors, and therefore this paper proposes an automatic AVR measurement method to address the low precision issue of manual measurement. MethodWe develop an improved feature extraction module for vertebral landmark detection and pedicle segmentation. The improved coordinate convolution layer combined Polarized Self-Attention mechanism is applied in the feature extraction module to help the High-resolution Network to extract coordinate information. Based on vertebral landmark detection and pedicle segmentation, we propose an automatic AVR measurement algorithm to estimate the AVR. ResultsThe mean radial error (MRE) of vertebral landmark detection is 2.70 mm pixels, and the dice coefficient of pedicle segmentation is 72.45%. Compared with the original model, the MRE decreases by 2.13 mm, and the dice coefficient improves by 4.61%. For the AVR measurement results, the testing set contains 37 spine radiographs, including 481 vertebrae and 962 AVR measurements (481 vertebrae by two observers). The average measurement error is lower than 5°, which is within the standard of clinical measurement error. ConclusionThe results demonstrate that the proposed network performs well in vertebral landmark detection and pedicle segmentation, and the proposed AVR measurement is adopted for clinic diagnosis of AIS. SignificanceOur method achieves automatic AVR measurement, reducing the error introduced by manual measurement and improving the efficiency of orthopedists.

A case study of the association between adolescent idiopathic scoliosis, weight training and shoulder dislocation

This study shows a rare association between the anomalous position of the shoulder girdle, due to scoliosis, with altered shoulder kinematics, injury of joint capsule ligaments and rotator cuff tendons, and shoulder dislocation due to a traumatic event. The subject has developed adolescent idiopathic scoliosis, with convex curvatures to the right side in the lower region of the thorax (with the Cobb angle of 13 degrees) and to the left side of the upper region of the thorax (with the Cobb angle of 24-degrees), both of them with the axial rotation of vertebra and with visible gibbosities. The upper axial rotation has a 6.5-degree, which causes an unbalance between the two shoulder girdles. In normal situations, the shoulder joint is turned 30 degrees anterior to the coronal plane, but in his case, the right shoulder girdle is pulled 28 degrees anterior by the groove, and the left one is pushed 34.5 degrees anterior by the gibbosity. The major effect of shoulder girdle unbalance appears to be the maximum extension of the upper limbs when the hands can’t be aligned to the coronal plane and this is an important risk factor for the injuries of the left shoulder joint, while some weight training exercises are performed.

Direct Vertebral Rotation (DVR) Does Not Improve Clinical and Radiological Results Compared to Differential Rod Contouring (DRC) in Patients Treated Surgically for Idiopathic Scoliosis.

Direct vertebral rotation (DVR) is the most widespread method to correct axial vertebral rotation. Differential rod contouring (DRC) also includes derotation, but not to the same extent as DVR. DVR requires additional surgical effort with potential consequences, which are absent in DRC; moreover, the data concerning the clinical benefits of apical derotation are not convincing. In the present study, clinical and radiological outcomes were compared in patients who underwent surgery for adolescent idiopathic scoliosis (AIS), having DVR and DRC vs. DRC only. In total, 73 AIS patients with curves of 40-85°, consecutively operated on by one surgeon, participated in this study and were followed up over 2 years. Scores from the SRS-22 questionnaire were analysed, the angles of trunk rotation (ATR) were measured with an inclinometer and a radiographic assessment of coronal and sagittal spinal profiles was conducted. In 38 cases, only DRC was performed, and in 35 DRC was performed and followed by DVR; the groups did not differ from an epidemiological point of view. Total SRS-22 scores after 2 years were similar in both groups (4.23 (±0.33) in DRC vs. 4.06 (±0.33) in DRC/DVR, p = 0.1). In all components of SRS-22, the differences were minor, with p being way above 0.05. The mean ATR in the DRC/DVR group was slightly smaller (8 ± 4°) than that of the DRC group (10 ± 5°), p = 0.16. Radiographic analysis did not show significant differences. The coronal curve was corrected by 66 ± 12% for DRC and 63 ± 15% for DVR, p = 0.28. Thoracic kyphosis in the DRC/DVR group increased by 1°, whereas in the DRC group the average kyphosis increased by 5° with a p value of 0.07. The complication rates were similar in both groups. This investigation did not show any advantages of the combination of DRC and DVR in scoliosis correction over DRC only, both radiologically and clinically, yet it affected intraoperative parameters, extending the operation time with only a minor increase in blood loss.

Three-dimensional ultrasonography could be a potential non-ionizing tool to evaluate vertebral rotation of subjects with adolescent idiopathic scoliosis.

Three-dimensional (3D) ultrasonography is nonionizing and has been demonstrated to be a reliable tool for scoliosis assessment, including coronal and sagittal curvatures. It shows a great potential for axial vertebral rotation (AVR) evaluation, yet its validity and reliability need to be further demonstrated. Twenty patients with adolescent idiopathic scoliosis (AIS) (coronal Cobb: 26.6 ± 9.1°) received 3D ultrasound scan for twice, 10 were scanned by the same operator, and the other 10 by different operators. EOS Bi-planar x-rays and 3D scan were conducted on another 29 patients on the same day. Two experienced 3D ultrasonographic researchers, with different experiences on AVR measurement, evaluated the 3D ultrasonographic AVR of the 29 patients (55 curves; coronal Cobb angle: 26.9 ± 11.3°). The gold standard AVR was determined from the 3D reconstruction of coronal and sagittal EOS radiographs. Intra-class correlation coefficients (ICCs), mean absolute difference (MAD), standard error measurements (SEM), and Bland-Altman's bias were reported to evaluate the intra-operator and inter-operator/rater reliabilities of 3D ultrasonography. The reliability of 3D ultrasonographic AVR measurements was further validated using inter-method with that of EOS. ICCs for intra-operator and inter-operator/rater reliability assessment were all greater than 0.95. MAD, SEM, and bias for the 3D ultrasonographic AVRs were no more than 2.2°, 2.0°, and 0.5°, respectively. AVRs between both modalities were strongly correlated (R 2 = 0.901) and not significantly different (p = 0.205). Bland-Altman plot also shows that the bias was less than 1°, with no proportional bias between the difference and mean of expected and radiographic Cobb angles. This study demonstrates that 3D ultrasonography is valid and reliable to evaluate AVR in AIS patients. 3D ultrasonography can be a potential tool for screening and following up subjects with AIS and evaluating the effectiveness of nonsurgical treatments.

Scoliosis Management through Apps and Software Tools.

Background: Scoliosis is curvature of the spine, often found in adolescents, which can impact on quality of life. Generally, scoliosis is diagnosed by measuring the Cobb angle, which represents the gold standard for scoliosis grade quantification. Commonly, scoliosis evaluation is conducted in person by medical professionals using traditional methods (i.e., involving a scoliometer and/or X-ray radiographs). In recent years, as has happened in various medicine disciplines, it is possible also in orthopedics to observe the spread of Information and Communications Technology (ICT) solutions (i.e., software-based approaches). As an example, smartphone applications (apps) and web-based applications may help the doctors in screening and monitoring scoliosis, thereby reducing the number of in-person visits. Objectives: This paper aims to provide an overview of the main features of the most popular scoliosis ICT tools, i.e., apps and web-based applications for scoliosis diagnosis, screening, and monitoring. Several apps are assessed and compared with the aim of providing a valid starting point for doctors and patients in their choice of software-based tools. Benefits for the patients may be: reducing the number of visits to the doctor, self-monitoring of scoliosis. Benefits for the doctors may be: monitoring the scoliosis progression over time, managing several patients in a remote way, mining the data of several patients for evaluating different therapeutic or exercise prescriptions. Materials and Methods: We first propose a methodology for the evaluation of scoliosis apps in which five macro-categories are considered: (i) technological aspects (e.g., available sensors, how angles are measured); (ii) the type of measurements (e.g., Cobb angle, angle of trunk rotation, axial vertebral rotation); (iii) availability (e.g., app store and eventual fee to pay); (iv) the functions offered to the user (e.g., posture monitoring, exercise prescription); (v) overall evaluation (e.g., pros and cons, usability). Then, six apps and one web-based application are described and evaluated using this methodology. Results: The results for assessment of scoliosis apps are shown in a tabular format for ease of understanding and intuitive comparison, which can help the doctors, specialists, and families in their choice of scoliosis apps. Conclusions: The use of ICT solutions for spinal curvature assessment and monitoring brings several advantages to both patients and orthopedics specialists. Six scoliosis apps and one web-based application are evaluated, and a guideline for their selection is provided.

Does Laminectomy Affect Spino-Pelvic Balance in Lumbar Spinal Stenosis? A Study Based on the EOS X-Ray Imaging System.

Lumbar spinal stenosis (LSS) is a degenerative disorder causing the forward bending of the trunk and pelvic retroversion with the consequent loss of lumbar lordosis; surgical treatment is intended to enlarge the canal and foramina and decompress the nerve roots. The purpose of our study is to determine whether and to what extent facet-sparing laminectomy affects the spino-pelvic balance. The spino-pelvic balance of 26 patients was analysed before and after surgery through the EOS X-ray Imaging System. The following parameters were considered: thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS). Clinical data were expressed in numeric values according to the Oswestry Disability Index (ODI), the visual analogue scale (VAS) and the modified Japanese Orthopaedic Association (mJOA) scoring system. Significant SS decreases and PT increases were noticed after surgery, without modification in LL, axial vertebral rotation (AVR) and the general alignment. Pain and disability had a significant improvement, as represented by a decrease in scores on the VAS and ODI scales and an increase in scores on the mJOA functional scale. The most important parameter seems to be a congruence between pelvic and spinal parameters, which achieves an economic posture with the physiologic position of the axis of gravity. According to the literature, a standard sagittal balance (SB) has not been defined.

Posterior Multisegment Apical Convex plus Concave Intervertebral Release Combined with Posterior Column Osteotomy for the Treatment of Rigid Thoracic/Thoracolumbar Scoliosis

Intervertebral release (IVR) in the apical region is critical for full release of a rigid spine. Previous studies have mainly reported IVR techniques using an anterior approach or posterior apical convex IVR. We first report the surgical procedure of posterior multisegment apical convex plus concave IVR combined with posterior column osteotomy (PCO) for treating rigid thoracic/thoracolumbar scoliosis. This study retrospectively analyzed clinical, radiologic outcomes and technique notes of 18 patients with rigid scoliosis treated with posterior multisegment convex plus concave IVR combined with PCO. The preoperative, postoperative, and final follow-up mean sagittal Cobb angles of the main curve were 75.2° (58.7°-110.2°), 18.4° (9°-35.1°), and 19.0° (8.2°-36.3°), respectively. The mean correction rate was 75.3% (66.7%-86.7%). In cases of thoracolumbar kyphosis, the preoperative, postoperative, and final follow-up mean sagittal Cobb angles were 45.7° (40.5°-52.6°), 18.8° (10.2°-27.5°), and 19.8° (11.1°-29°), respectively. The mean correction rate was 57% (42.1%-72.6%). The mean axial vertebral rotation (AVR) in the IVR region was 24.4° (14.3°-46.3°) preoperatively and was corrected to 10.9° (10.9°-26.6°) postoperatively. The mean correction rate for AVR was 55.9% (41.1%-78.6%). The coronal and sagittal Cobb angles and AVR postoperatively were significantly lower than those preoperatively (P < 0.001). This case series reported 2 cases of pleural effusion and 1 case of wound infection. Single posterior multilevel apical convex plus concave IVR combined with PCO is a safe and effective surgical method for treating rigid thoracic/thoracolumbar scoliosis that does not need 3-column osteotomy.

Is posteromedial translation with sublaminar bands effective in correcting axial rotation in adolescent idiopathic scoliosis surgery? A 3D reconstruction study.

Hybrid constructs with sublaminar bands have recently regained popularity as an alternative to all-screw construct for correction of adolescent idiopathic scoliosis (AIS). The aim of this study is to evaluate the ability of hybrid constructs with sublaminar bands to achieve a tridimensional correction of the scoliotic deformity. Our hypothesis is that hybrid construct with sublaminar bands are able to achieve a substantial derotation of the apical vertebrae, while preserving the thoracic kyphosis. A prospective evaluation of 50 consecutive cases (41 F, 9M, mean age 14.7 ± 2years) of AIS correction with hybrid construct was performed. In all cases, sublaminar bands were used at the apex of the main curve on concave side. All patients underwent pre and postoperative X-rays with EOS System, with full 3D reconstruction. Spinopelvic parameters and axial rotation of the vertebrae were measured pre and postoperatively. 2.7 ± 0.9 mean sublaminar bands were used per patient. Mean correction of deformity was 50 ± 9.5%. on the coronal plane. The mean axial rotation of the apical vertebra went from 18° ± 11.5° preoperatively to 9.4° ± 7.2° postoperatively (p < 0.001) with a mean derotation of 47.7%. Thoracic kyphosis went from 32.1° ± 18° preoperatively to 37.3° ± 13.1° postoperatively (p < 0.05). No intraoperative complications due to sublaminar bands were recorded. Hybrid construct with sublaminar band have been showed to be safe and effective in deformity correction and in maintaining or restoring thoracic kyphosis. This study showed that with sublaminar bands applied at the curve apex a substantial derotation of the apical vertebrae can be achieved.