Main Thoracic Cobb Angle Research Articles

Changes in trunk appearance following surgical correction of adolescent idiopathic scoliosis.

To assess the postoperative appearance of the trunk in surgically treated scoliosis patients after a 2 year follow-up using reliable indices and compare the results with 6-month follow-up. Forty-six Adolescent Idiopathic Scoliosis (AIS) patients (female; preop mean age 14.4 ± 2.4years) who underwent a posterior spinal fusion from 2009 to 2018 were included in this study. All had Lenke 1A thoracic curves, with surface topography taken preoperatively, 6months and 2years postoperatively. To assess spinal deformity, we measured the proximal thoracic, main thoracic and thoracolumbar/lumbar Cobb angles in the frontal plane from spinal X-rays and inclinometer angles in the thoracic and lumbar regions. To assess trunk deformity, Back Surface Rotation (BSR) and Trunk Lateral Shift (TLS) were computed along the trunk. We analysed the effect of age, height, weight, Cobb angle, length of follow-up, and surgical technique. We also compared correction rates (CRs) of the spinal and trunk measurements after 6months and 2years. Good spinal correction was achieved, with Cobb angles decreasing in the whole cohort. CRs for TLS and BSR were positive (denoting improvement) for 76% and 48% of patients, respectively, after 2years. Compared with 6months, the mean TLS CR increased while there was no improvement for BSR on average. We found no significant association after 2years between truncal index CRs and clinical variables (age, height, weight, preoperative Cobb angles) or surgical technique. However, there were significant correlations between the CRs of TLS and the main thoracic Cobb angle (r = 0.35), and between the CRs of BSR and thoracic inclinometer angle. Although more than 55% of the TLS was corrected after 2years of follow-up, the BSR remained stable over time and the persistence of rib hump on the back surface could be observed. III.

What is the prevalence and distribution of narrow dysplastic and fully corticalized pedicles in Asian adolescent idiopathic scoliosis patients with major main thoracic curves? A computed tomography scan analysis of 6,494 pedicles

BACKGROUND CONTEXTPatients with adolescent idiopathic scoliosis (AIS) have higher prevalence of abnormal or dysplastic pedicles. PURPOSETo investigate the prevalence and distribution of narrow dysplastic and fully corticalized pedicles in Asian AIS patients with major main thoracic curves. DESIGNRetrospective study. PATIENT SAMPLEA total of 6,494 pedicles in 191 patients were measured and evaluated. OUTCOME MEASURESThe primary outcomes measures were the pedicle width measurements (total transverse pedicle width, transverse cancellous width, total transverse cortical width) and classification of pedicles. Demographic data (age, gender, height, weight, body mass index), proximal thoracic Cobb angle, main thoracic Cobb angle and lumbar Cobb angle were also obtained. METHODSAIS patients with major (largest Cobb angle) main thoracic curves and had computed tomography (CT) scans prior to corrective spine surgery were reviewed. The pedicles were classified as Grade A: cancellous channel >4 mm; Grade B: cancellous channel 2 to 4 mm; Grade C: cancellous channel <2 mm or corticalized pedicle >4 mm; Grade D: corticalized pedicle ≤4 mm. Grades B, C, and D were dysplastic pedicles while grades C and D were narrow dysplastic pedicles. RESULTSThe prevalence of dysplastic pedicles (grades B, C, and D) was 61.7%. There were 22.6% narrow dysplastic pedicles (grades C and D) and 4.1% fully corticalized pedicles (grade D). In the thoracolumbar region, there was a sharp transition from larger and less dysplastic pedicles at T11 and T12 to narrower and more dysplastic pedicles at L1 and L2 (narrow dysplastic pedicles at T11: 3.1%, T12: 3.1%, L1: 39.8% and L2: 23.6%). Higher prevalences of narrow dysplastic pedicles were located at right T3 to T5 (71.2%–83.7%) and left T7-T9 (51.3%–61.2%). Higher prevalences of fully corticalized pedicles were located at right T3 to T5 (20.9%–34.0%) and left T7 to T8 (11.0%–12.0%). These were the concave pedicles of proximal thoracic and main thoracic curves, respectively. CONCLUSIONThere were 95.9% pedicles with cancellous channels (grades A, B, and C) can allow pedicle screw fixation and only 4.1% fully corticalized pedicles (grade D) that require an alternative method of fixation. For grade C pedicles (18.5%), pedicle screws can still be attempted with caution. Precautions should also be observed at the L1 and L2 levels as there was a transition to narrower pedicles.

Utilization of pre-operative MRI to identify AIS patients at highest risk of intra-operative neuromonitoring alert.

Utility of pre-operative MRI for patients undergoing scoliosis correction has expanded to include an MRI classification for identifying patients at increased risk of experiencing intra-operative neuromonitoring (IONM) alerts based on the shape of the spinal cord and circumferential presence of CSF at the apex of the thoracic curve. In the present study, the authors explore the utility of this new MRI classification and multiple X-ray radiographic parameters in identifying the AIS sub-population at high risk of IONM alerts. AIS patients < 18years old who underwent posterior spinal fusion between 2018 and 2022 at a single institution. Imaging reviewed to determine main thoracic (MT) and thoraco-lumbar (TL) Cobb angles, major thoracic Apical Vertebral Translation (AVT) and lumbar/thoraco-lumbar AVT (TL AVT), thoracic kyphosis (TK), coronal main thoracic Deformity Angular Ratio (cDAR), sagittal DAR (sDAR), and MRI to determine the spinal cord type (1, 2, or 3). A total of 155 AIS patients who met the inclusion criteria between 2018 and 2022 were included. There was a trend to have an increased incidence of Type 3 spinal cord shape both with increase in the MT Cobb angle and MT AVT. There was also a shift toward more IONM alerts in patients with Type 3 (19.5%) spinal cords, AVT ≥ 5cm (18.9%), and Cobb angle ≥ 650 (28.2%). Higher magnitude of thoracic Cobb angle and AVT are associated with higher likelihood of type 3 spinal cord at the apex in MRI. Patients with Type 3 spinal cord, Cobb angle ≥ 650, AVT > 5cm, and cDAR > 10 have higher likelihood to have IONM alerts. Patient with a Type 3 spinal cord and a Cobb angle ≥ 650 (50.0%), cDAR > 10 (43.7%), and AVT > 5cm (35.2%) have the highest risk of having IONM alerts.

Thoracoscopic Anterior Vertebral Body Tethering in Lenke Type-1 Right Adolescent Idiopathic Scoliosis.

Vertebral body tethering (VBT) is indicated for skeletally immature patients with progressive adolescent idiopathic scoliosis (AIS) who have failed or are intolerant of bracing and who have a major coronal curve of 40° to 65°. The vertebral body must be structurally and dimensionally adequate to accommodate screw fixation, as determined radiographically. The best indication for VBT is a flexible single major thoracic curve with nonstructural compensating lumbar and proximal thoracic curves (Lenke 1A or 1B). VBT allows for progressive correction of the deformity without spinal fusion by utilizing a minimally invasive fluoroscopic technique. The procedure for a right thoracic curve is performed with use of a right thoracoscopic approach with the patient in the left lateral decubitus position. The thoracoscope is introduced through a portal at the apex of the curvature in the posterior axillary line. Instrument portals are created lateral to each vertebral body in the mid-axillary line. Screws are inserted into each vertebral body under biplanar fluoroscopic control and with intraoperative neuromonitoring. An electroconductivity probing device, while not mandatory, is routinely utilized at our practice. The tether is attached to the most proximal screw of the construct, and then reduction is obtained sequentially by tensioning the tether from one vertebral screw to the next. Bracing is the gold-standard treatment for progressive AIS involving the immature spine. The most commonly utilized surgical treatment is posterior spinal fusion (PSF), which should be considered when the major coronal curve exceeds 45°. PSF has proven to be a dependable technique to correct scoliotic deformities. It has a low complication rate and good long-term outcomes. However, concerns exist regarding the stiffness conferred by PSF and the long-term effects of adjacent segment disease. Thus, interest had developed in non-fusion solutions for AIS correction. VBT utilizes the Hueter-Volkmann principle to guide growth and correct deformity. Compressive forces applied to the convexity of the deformity by a polyethylene tether allow the patient's growth to realign the spine. Intraoperative correction triggers growth modulation, and most of the modulation seems to occur during the first 12 months postoperatively. The best results have been seen with a short Lenke type-1A curve in a patient with closed triradiate cartilage, a Risser 3 or lower (ideally Risser 0) iliac apophysis, and a flexible curve characterized by a 50% reduction of the major coronal curve angle on side-bending radiographs. In 57 immature patients with a Lenke type-1A or 1B curve (i.e., a 30° to 65° preoperative Cobb angle), Samdani et al.3 found a main thoracic Cobb angle reduction from 40° ± 7° preoperatively to 19° ± 13° at 2 years after VBT. In the sagittal plane, the T5-T12 kyphosis measured 15° ± 10° preoperatively, 17° ± 10° postoperatively, and 20° ± 13° at 2 years. No major neurologic or pulmonary complications occurred. A total of 7 (12.3%) of the 57 patients underwent surgical revision, including 5 for overcorrection and 2 to span additional vertebrae. In a study of 21 skeletally mature patients, Pehlivanoglu et al.4 found that the Cobb angle was reduced from 48° preoperatively to 16° on the first-erect postoperative radiograph and finally to 10° at the latest follow-up (mean, 27.4 months). The 2 main complications of VBT reported in the literature are overcorrection and tether breakage. Both may require revision, which explains the higher rate of revision observed for VBT compared with PSF. Good patient selection is important. VBT is most appropriate in cases of a flexible Lenke type-1A or 1B curve in an immature child before Risser stage 3 and after triradiate cartilage closure.Always monitor and control screw positioning in both anteroposterior and lateral planes fluoroscopically.The screws should be placed parallel to the vertebral end plates or, even better, be angled inferiorly for the upper vertebrae and angled superiorly for the lower vertebrae to decrease the risk of pull-out when tensioning the device and during growth modulation. Less tension on the uppermost and lowermost instrumented vertebrae than at the apex, as controlled by the tensioning device, can also help to limit pull-out. VBT = vertebral body tetheringAIS = adolescent idiopathic scoliosisIONM = intraoperative neuromonitoringPSF = posterior spinal fusionUIV = upper instrumented vertebraLIV = lower instrumented vertebraAP = anteroposteriorK-wire = Kirschner wire.

Biomechanical Computational Study of Pedicle Screw Position and Density in Adolescent Idiopathic Scoliosis Instrumentation.

Computer simulation of adolescent idiopathic scoliosis instrumentation. To test the hypothesis that different screw densities would result in different apical vertebral rotation (AVR) corrections and bone-screw forces in adolescent idiopathic scoliosis instrumentation. The "Minimize Implants Maximize Outcomes" Clinical Trial revealed that the use of more versus fewer screws resulted in similar coronal plane correction for Lenke 1A curves. However, the biomechanical impact of screw density on transverse plane correction is still unclear. Further investigation is needed to determine if and how transverse plane correction is correlated with screw density. We simulated apical vertebral derotation after segmental translation using patient-specific computer models of 30 patients from the "Minimize Implants Maximize Outcomes" Trial. For each case, 10 alternative screw patterns were tested with overall densities ranging between 1.2 and 2 screws per level fused, and local density at the 3 apical levels ranging between 0.7 and 2 (total: 600 simulations). Main thoracic (MT) Cobb angle, thoracic kyphosis (TK), AVR, and bone-screw forces were computed and compared. The presenting MT (62 ± 11°; range: 45° to 86°), TK (27 ± 20°; -5° to 81°), and AVR (14±7°; -2° to 25°) were corrected through segmental translation to 22 ± 7° (10° to 41°), 26 ± 5° (18° to 45°), and 14 ± 7° (-4° to 26°). After apical vertebral derotation, they became 16 ± 8° (1° to 41°), 24 ± 4° (13° to 40°), and 4 ± 5° (-12° to 18°). There was no significant difference in MT among screw patterns; higher screw density had lower bone-screw forces ( P < 0.05). The apical vertebral derotation maneuver reduced AVR by an average of 70%, positively correlated with apical screw density ( r = 0.825, P < 0.05). There was no significant difference in TK. Screw density had no significant effect on 3-dimensional correction through the primary segmental translation maneuver. Transverse plane correction through subsequent apical vertebral derotation was positively correlated with screw density at the apical levels ( r = 0.825, P < 0.05). Bone-screw forces were negatively correlated with overall screw density ( P < 0.05).

Are We Looking at a Paradigm Shift in the Management of Adolescent Idiopathic Scoliosis? Comprehensive Retrospective Analysis of 75 Patients of Nonfusion Anterior Scoliosis Correction with 2-5-Year Follow-up: A Single Center Experience.

Retrospective cohort study. This study aimed to evaluate the clinical and radiological outcomes of nonfusion anterior scoliosis correction (NFASC) in patients with idiopathic scoliosis and comprehensively analyze its principles. NFASC is a novel revolutionary motion-preserving surgery for idiopathic scoliosis. However, clinical data related to this procedure remain scarce, with no conclusive guidelines regarding case indications, proper technique, and possible complications. This study included patients with adolescent idiopathic scoliosis (AIS) who were treated with NFASC for a structural major curve (Cobb angle, 40°-80°) with more than 50% flexibility on dynamic X-rays. The mean follow-up was 26±12.2 months (range, 12- 60 months). Clinical and radiological data such as skeletal maturity, curve type, Cobb angle, surgery details, and Scoliosis Research Society-22 revised (SRS-22r) questionnaire were collected. Statistically significant trends were examined by post hoc analysis following repeated measures analysis of variance test. A total of 75 patients (70 females, five males) were included, with a mean age of 14.96±2.69 years. The mean Risser and Sanders scores were 4.22±0.7 and 7.15±0.74, respectively. The mean main thoracic Cobb angles at the first and second follow-up (17.2°±5.36° and 16.92°±5.06°, respectively) were significantly lower than the preoperative Cobb angles (52.11°±7.74°) (p <0.05). Similarly, the mean thoracolumbar/lumbar Cobb angle significantly improved from the preoperative period (51.45°±11.26°) to the first follow-up (13.48°±5.11°) and last follow-up (14.24°±4.85°) (p <0.05). The mean preoperative and postoperative SRS-22r scores were 78.0±3.2 and 92.5±3.1, respectively (p <0.05). None of the patients had any complications until the most recent follow-up. NFASC offers promising curve correction and curve progression stabilization in patients with AIS, with a low risk for complications and preservation of spinal mobility and sagittal parameters. Thus, it proves to be a favorable alternative to fusion modality.

TWO-YEAR FOLLOW-UP STUDY FOR PATIENTS UNDERGOING VERTEBRAL BODY TETHERING FOR IDIOPATHIC SCOLIOSIS

Anterior vertebral body tethering (AVBT) is a growth modulating procedure used to manage idiopathic scoliosis by applying a flexible tether to the convex surface of the spine in skeletally immature patients. The purpose of this study is to determine the preliminary clinical outcomes for an adolescent patient cohort.18 patients with scoliosis were selected using a narrow selection criteria to undergo AVBT. Of this cohort, 11 had reached a minimum follow up of 2 years, 4 had reached 18 months, and 3 had reached 6 months. These patients all demonstrated a primary thoracic deformity that was too severe for bracing, were skeletally immature, and were analysed in this preliminary study of coronal plane deformity correction.Using open-source image analysis software (ImageJ, NIH) PA radiographs taken pre-operatively and at regular follow-up visits post-operatively were used to measure the coronal plane deformity of the major and compensatory curves.Pre-operatively, the mean age was 12.0 years (S.D. 10.7 – 13.3), mean Sanders score 2.6 (S.D. 1.8-3.4), all Risser 0 and pre-menarchal, with mean main thoracic Cobb angle of 52° (S.D. 44.2-59.8°). Post-operatively the mean angle decreased to 26.4° (S.D. 18.4-32°) at 1 week, 30.4° (S.D. 21.3-39.6°) at 2 months, 25.7° (S.D. 18.7-32.8°) at 6 months, 27.9° (S.D. 16.2-39.6°) at 12 months, and 36.8° (S.D. 22.6– 51.0°) at 18 months and 38.2° (S.D. 27.6-48.7°) at 2 years. The change in curve at 2 years post-operative was statistically significant (P=0.004).There were 4 tether breakages identified that did not require return to theatre as yet, one patient underwent a posterior spinal instrumented fusion due to curve progression.AVBT is a promising new growth modulation technique for skeletally immature patients with progressive idiopathic scoliosis. This study has demonstrated a reduction in scoliosis severity.

Effect of clinical and radiological parameters on the quality of life in adult patients with untreated adolescent idiopathic scoliosis: a cross-sectional study.

The aim of this study is to evaluate the factors that affect health-related quality of life (HRQoL) in untreated adolescent idiopathic scoliosis (AIS) patients in adulthood. We investigate the effect of clinical and radiological parameters on the SRS-22 results. A total of 286 untreated adolescent idiopathic scoliosis patients at adult age between April 2021 and April 2022 who were admitted to our clinic were included in the study. Rotational deformities were evaluated with a scoliometer. Cobb angles, coronal balance, clavicle angle, coronal pelvic tilt, trunk shift, and apical vertebral translation were measured in standing anteroposterior X-rays. The effect of each clinical and radiological parameter on SRS-22 results was evaluated. No correlation was found between gender, age, curve type, presence of gibbosity or diagnosis time, and SRS-22 scores. A negative correlation was found between the BMI of the patients and the self-image scores (r = - 0.246, p < 0.01) and function scores (r = - 0.193, p < 0.05). Main thoracic (MT) gibbosity negatively correlates with self-image and total SRS-22 scores. Also, negative correlations were found between lumbar/thoracolumbar (LTL) gibbosity, function, and pain scores. MT Cobb angle magnitude was negatively correlated with self-image, mental health, and total SRS-22 scores. There were negative correlations between clavicle angle and mental health score, coronal pelvic tilt and self-image score, and apical vertebral translation and pain score. BMI, MT gibbosity, LTL gibbosity, MT Cobb angle, clavicle angle, coronal pelvic tilt, and apical vertebral translation were negatively correlated with SRS-22 domains in untreated AIS patients in adulthood.

Prediction of Post-operative Clinical Indices in Scoliosis Correction Surgery Using an Adaptive Neuro-fuzzy Interface System.

Accurate estimation of post-operative clinical parameters in scoliosis correction surgery is crucial. Different studies have been carried out to investigate scoliosis surgery results, which were costly, time-consuming, and with limited application. This study aims to estimate post-operative main thoracic cobb and thoracic kyphosis angles in adolescent idiopathic scoliosis patients using an adaptive neuro-fuzzy interface system. Distinct pre-operative clinical indices of fifty-five patients (e.g., thoracic cobb, kyphosis, lordosis, and pelvic incidence) were taken as the inputs of the adaptive neuro-fuzzy interface system in four categorized groups, and post-operative thoracic cobb and kyphosis angles were taken as the outputs. To evaluate the robustness of this adaptive system, the predicted values of post-operative angles were compared with the measured indices after the surgery by calculating the root mean square errors and clinical corrective deviation indices, including the relative deviation of post-operative angle prediction from the actual angle after the surgery. The group with inputs for main thoracic cobb, pelvic incidence, thoracic kyphosis, and T1 spinopelvic inclination angles had the lowest root mean square error among the four groups. The error values were 3.0° and 6.3° for the post-operative cobb and thoracic kyphosis angles, respectively. Moreover, the values of clinical corrective deviation indices were calculated for four sample cases, including 0.0086 and 0.0641 for the cobb angles of two cases and 0.0534 and 0.2879 for thoracic kyphosis of the other two cases. In all scoliotic cases, the post-operative cobb angles were lesser than the pre-operative ones; however, the post-operative thoracic kyphosis might be lesser or higher than the pre-operative ones. Therefore, the cobb angle correction is in a more regular pattern and is more straightforward to predict cobb angles. Consequently, their root-mean-squared errors become lesser values than thoracic kyphosis.

Shoulder Imbalance in Adolescent Idiopathic Scoliosis: A Systematic Review of the Current State of the Art.

Shoulder imbalance (SI) is among the most rated manifestations of adolescent idiopathic scoliosis (AIS) pointed to by patients and spine surgeons. It serves as a criterion to assess the outcome of scoliosis surgery and is also a cause of dissatisfaction for the patients postoperatively. Despite the availability of multiple studies on this issue, a comprehensive survey of the risk factors and preventive measures has yet to be elucidated. The present study aimed to highlight the most recent approach to the evaluation and management of SI, as well as medical counseling about the expectations and limitations of the surgery. A systematic literature review using electric databases was conducted, including PubMed, Embase, the Cochrane Library, and Google Scholar, with a well-defined search strategy on SI definition, risk factors, and preventive and surgical recommendations. A total of 69 articles were identified; SI > 2 cm was the most used cut-off, and its risk factors included the main thoracic Cobb angle > 80˚, preoperative level shoulder, high left shoulder, and higher Risser grade. The most stated strategies to preclude SI were the sufficient correction of the proximal thoracic curve, and moderate correction of the main thoracic and lumbar curve (LC). Shoulder imbalance should be prevented not only for appearance or satisfaction but also for possible complications such as distal adding-on, new LC progression, or trunk shift postoperatively in AIS patients.

How much residual deformity is acceptable according to SRS-22r and satisfaction scores after posterior spinal fusion for Lenke type 1 and 2 curves in adolescent idiopathic scoliosis?

In recent years, it has become possible to predict postoperative correction and residual deformity in adolescent idiopathic scoliosis (AIS) surgery based on the technique used and extent of fixation. However, the recommended degree of correction has not yet been established. In this study, the authors aimed to clarify the extent to which a residual postoperative deformity would be acceptable according to Scoliosis Research Society (SRS)-22r and satisfaction scores after AIS surgery. Overall, 92 patients who underwent posterior spinal fusion for Lenke type 1 or 2 AIS were retrospectively included. The Patient Acceptable Symptom State (PASS) cutoff values for each SRS-22r domain were calculated using receiver operating characteristic (ROC) curves to obtain predictive values of treatment satisfaction 2 years after surgery. Multivariate logistic regression analysis was performed with deformity parameters and demographic data as explanatory variables, and achieving the PASS cutoff value of each SRS-22r domain and treatment satisfaction were objective variables. Cutoff values were calculated using ROC analysis. The PASS cutoff values for SRS-22r domains were 3.69 (area under the ROC curve [AUC] 0.86) for self-image, 4.25 (AUC 0.82) for mental health, and 4.22 (AUC 0.82) for the subtotal. The residual main thoracic Cobb angle was not remarkably related to SRS-22r or treatment satisfaction. The residual thoracolumbar/lumbar (TL/L) Cobb angle was significantly associated with treatment satisfaction, with a cutoff value of 12.5° (AUC 0.75). The parameters of deformity that were significantly associated with achieving the PASS cutoff value for self-image were the TL/L Cobb angle and main thoracic apical vertebral translation, although their respective AUCs were < 0.7. In patients with Lenke type 1 and 2 AIS, the residual postoperative TL/L Cobb angle was significantly associated with achieving the PASS cutoff values for self-image and treatment satisfaction. Satisfaction with treatment was more likely when the TL/L Cobb angle was ≤ 12.5°.

Postoperative shoulder balance in Lenke type 1 adolescent idiopathic scoliosis patients with large thoracic curve (Cobb angle ≥ 70 degrees): a radiographic study

BackgroundLarge amounts of thoracic curve correction had been considered as a risk factor for postoperative shoulder imbalance (PSI) in adolescent idiopathic scoliosis (AIS) patients. This study aims to evaluate postoperative shoulder balance in Lenke type 1 AIS patients with large thoracic curve (Cobb angle ≥ 70 degrees) and compared it with those with moderate thoracic curve (Cobb angle < 70 degrees).MethodsA total of 47 Lenke type 1 AIS patients underwent posterior correction surgery between Sept. 2016 to Nov. 2018 in our institution were included. All these patient were divided into 2 groups based on the severity of main thoracic (MT) curve. Group A consisted of 25 cases with MT curve equal to or more than 70 degree while Group B consisted of 22 cases with MT curve less than 70 degree. Proximal thoracic (PT) Cobb angle, MT Cobb angle, MT apical vertebral translation (AVT), T2-T5 kyphosis, T5-T12 kyphosis, and radiographic shoulder height (RSH) were compared between these 2 groups preoperatively, immediately after surgery, and at a minimum of two-year follow-up.ResultsAlthough all the correction of PT Cobb angle (15.8° ± 6.0° vs 12.5° ± 3.6°, P = 0.028), that of MT Cobb angle 47.3° ± 9.1° vs 30.9° ± 6.7°, P < 0.001) and that of MT AVT (35.1 mm ± 16.0 mm vs 24.1 mm ± 8.9 mm, P = 0.007) were significantly larger in Group A when compared with Group B, RSH was comparable between these 2 groups at last follow up (7.5 mm ± 7.4 mm vs 9.2 mm ± 4.2 mm P = 0.363). Most of the patients gained satisfactory shoulder balance with only 7 cases with minimal PSI in group A (28%) and only 6 cases with minimal PSI in group B (27.3%) at last follow-up (P > 0.05).ConclusionsAlthough Lenke type 1 AIS patients with large thoracic curve had more amounts of MT curve correction when compared with those with moderate thoracic curve, it did not lead to higher incidence of PSI if the correction rate is proper.

Hemoptysis due to progressive scoliosis associated with congenital heart disease: a case report

BackgroundPatients with congenital heart disease (CHD) are associated with an increased incidence of scoliosis, often with severe progression. We report a case of hemoptysis caused by rapid scoliosis progression subsequent to surgery for CHD that was successfully managed by surgical curve correction following coil embolization.Case presentationA 14-year-old girl with scoliosis had undergone open heart surgery for CHD at the age of 1 year. She was first noted to have scoliosis at 12 years of age, which began to progress rapidly. At age 13, her main thoracic curve Cobb angle was 46°, and hemoptysis with high pulmonary vein pressure due to vertebral rotation was detected. Nine months after coil embolization, she received posterior spinal fusion from T5 to L2 for scoliosis correction. Postoperatively, her pulmonary vein diameter was enlarged, with no detectable signs of hemoptysis.ConclusionsWe encountered a case of hemoptysis caused by advanced scoliosis after cardiac surgery that was successfully treated by correction of the scoliotic curve following coil embolization. Patients with secondary scoliosis after surgery for CHD should be carefully monitored for the possibility of cardiovascular system deterioration.

Posterior scoliosis correction with thoracoplasty: effect on pulmonary function with a mean follow-up of 4.8years.

To perform a study to investigate the influence of posterior scoliosis surgery and thoracoplasty on pulmonary function. This was a retrospective observational study of 37 patients with AIS who underwent posterior instrumented surgical correction with thoracoplasty. There was a minimum of 2years follow-up. Clinical outcomes were measured using the SRS-22 questionnaires. Radiological outcomes were evaluated using standing posteroanterior and lateral radiographs. All patients had pulmonary function tests to evaluate pulmonary volume and flow (forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC)) both before surgery and at the final follow-up. There were three males and 34 females. The mean age of patients was 14.6years (range 11-21years). The mean length of follow was 58months (range 24-124months). The average main thoracic Cobb angle in the coronal plane was corrected from 50.0° ± 12.4° preoperatively to 16.6° ± 6.3° postoperatively. The average thoracolumbar Cobb angle in the coronal plane was corrected from 28.2° ± 10.6° preoperatively to 10.1° ± 7.2°. The average thoracic kyphosis angle was corrected from 17.4° ± 11.0° preoperatively to 21.8° ± 10.5°. In terms of the Quality of life Outcomes (QoL), there was a significant increase (p < 0.001) in the mean SRS 22 scores from 3.8 preoperatively to 4.3 postoperatively. A statistically significant increase in the absolute forced expiratory volume in one second (FEV1) from pre-operative values with a p value < 0.001 was seen. There was a statistically significant increase in percentage predicted forced expiratory volume in one second from preoperative values with a p value of 0.008. There was also a statistically significant increase in the absolute forced vital capacity (FVC) from preoperative values with a p value < 0.001. The average percentage predicted forced vital capacity did increase on final follow-up from before surgery, but the increase was not statistically significant. We have demonstrated that pulmonary function post-thoracoplasty not only reaches pre-operative levels, but significantly surpasses it with regards to the majority of the pulmonary parameters measured in this study. We also demonstrated satisfactory radiological correction and clinical outcomes.

Anterior instrumentation surgery for the treatment of Lenke type 1AR curve patterns.

Previous studies have demonstrated that Lenke lumbar modifier A contains 2 distinct types (AR and AL), and the AR curve pattern is likely to develop adding-on (i.e., a progressive increase in the number of vertebrae included within the primary curve distally after posterior surgery). However, the results of anterior surgery are unknown. The purpose of this study was to present the surgical results in a cohort of patients undergoing scoliosis treatment for type 1AR curves and to compare anterior and posterior surgeries to consider the ideal indications and advantages of anterior surgery for type 1AR curves. Patients with a Lenke type 1 or 2 and lumbar modifier AR (L4 vertebral tilt to the right) and a minimum 2-year postoperative follow-up were included. The incidence of adding-on and radiographic data were compared between the anterior and posterior surgery groups. The numbers of levels between the end, stable, neutral, and last touching vertebra to the lower instrumented vertebra (LIV) were also evaluated. Forty-four patients with a mean follow-up of 57 months were included. There were 14 patients in the anterior group and 30 patients in the posterior group. The main thoracic Cobb angle was not significantly different between the groups preoperatively and at final follow-up. At final follow-up, the anterior group had significantly less tilting of the LIV than the posterior group (-0.8° ± 4.5° vs 3° ± 4°). Distal adding-on was observed in no patient in the anterior group and in 6 patients in the posterior group at final follow-up (p = 0.025). In the anterior group, no LIV was set below the end vertebra, and all LIVs were set above last touching vertebra. The LIV was significantly more proximal in the anterior group than in the posterior surgery patients without adding-on for all reference vertebrae (p < 0.001). This is the first study to investigate the surgical results of anterior surgery for Lenke type 1AR curve patterns, and it showed that anterior surgery for the curves could minimize the distal extent of the instrumented fusion without adding-on. This would leave more mobile disc space below the fusion.

3D quasi-automatic spine length assessment using low dose biplanar radiography after surgical correction in thoracic idiopathic scoliosis

ObjectiveSurgical correction of thoracic scoliosis leads to a height improvement. Our objectives were to assess how the linear and developed spinal column lengths relate to the frontal and sagittal parameters after a surgical correction of thoracic idiopathic scoliosis, and whether the measurement of these lengths is reliable using quasi-automatic 3D reconstruction methods with biplanar X-rays. MethodsConsecutive children with thoracic idiopathic scoliosis who underwent spinal fusion surgery and biplanar pre and postoperative X-rays in free-standing position were included prospectively. Quasi-automatic computed 3D reconstructions of the spine were done using a previously validated technique and allowed the automatic computation of geometrical spinopelvic parameters including OD-pelvis, linear, and developed T1-T12 and T1-L5 lengths. ResultsThirty patients with scoliosis were included, and 240 reconstructions were performed (2 operators x2 repetitions x30 patients pre and postoperative). The main thoracic Cobb angle, T1-T12, T1-L5 linear and developed distance, OD-pelvis were significantly improved (p < 0.001). The gain of the main thoracic Cobb angle (31.6°;SD = 9°) was correlated to the gain of the linear distance T1-T12 (15.3 mm;SD=7.3 mm)(rho = 0.76;p < 0.0001) and T1-L5 (24.7 mm;SD = 8 mm)(rho = 0.64;p < 0.0001). The postoperative change of developed length between T1-L5 represented 41% of the gain in linear distance between the same vertebrae. Similarly, the gain of T1-T12 developed length was 50% of linear T1-T12 height gain. Both differences were significant (p = 0.01). Absolute bias using Bland & Altman plots was lower than 1 mm for linear distance (0.1%) and lower than 2 mm (0.3%) for developed distance. ConclusionThe gain in spinal length is correlated to the thoracic Cobb angle correction in the surgical treatment of idiopathic thoracic scoliosis. The new significant finding is that the developed spinal height gain represented approximately a little less than 50% of the linear spinal height gain and these parameters were reliable from a 3D quasi-automatic reconstruction of biplanar X-ray.

Characteristics analysis of segmental and regional lumbar spontaneous compensation post thoracic fusion in Lenke 1 and 2 adolescent idiopathic scoliosis

ObjectiveTo explore the characteristics of compensation of unfused lumbar region post thoracic fusion in Lenke 1 and 2 adolescent idiopathic scoliosis.BackgroundPreserving lumbar mobility in the compensation is significant in controlling pain and maintaining its functions. The spontaneous correction of the distal unfused lumbar curve after STF has been widely reported, but previous study has not concentrated on the characteristics of compensation of unfused lumbar region post thoracic fusion.MethodA total of 51 Lenke 1 and2 AIS patients were included, whose lowest instrumented vertebrae was L1 from January 2013 to December 2019. For further analysis, demographic data and coronal radiographic films were collected before surgery, at immediate erect postoperatively and final follow-up. The wedge angles of each unfused distal lumbar segments were measured, and the variations in each disc segment were calculated at the immediate postoperative review and final follow-up. Meanwhile, the unfused lumbar curve was divided into upper and lower parts, and we calculated their curve angles and compensations.ResultsThe current study enrolled 41 females (80.4%) and 10 males (19.6%). Thirty-six patients were Lenke type 1, while 15 patients were Lenke type 2. The average main thoracic Cobb angle and thoracolumbar/lumbar Cobb angle were 44.1 ± 7.7°and 24.1 ± 9.3°, preoperatively. At the final follow-up, the disc wedge angle variation of L1/2, L2/3, L3/4, L4/5 and L5/S1 was 3.84 ± 5.96°, 3.09 ± 4.54°, 2.30 ± 4.53°, − 0.12 ± 3.89° and − 1.36 ± 2.80°, respectively. The compensation of upper and lower coronal lumbar curves at final follow-up were 9.22 ± 10.39° and − 1.49 ± 5.14°, respectively.ConclusionWhen choosing L1 as the lowest instrumented vertebrae, the distal unfused lumbar segments’ compensation showed a decreasing trend from the proximal end to the distal end. The adjacent L1/2 and L2/3 discs significantly contributed to this compensation.

The effect of delayed breast reconstruction after unilateral mastectomy on spine alignment.

Mastectomy in patients with breast cancer causes spinal deformities. We evaluated the effect of delayed breast reconstruction in post-mastectomy patients on spine alignments. The study included 68 patients who underwent delayed breast reconstruction by three plastic surgeons in a single tertiary hospital. We measured proximal thoracic (PT), main thoracic (MT), and thoracolumbar (TL) Cobb angles and coronal spinal balance from chest or whole spine radiographs. The median changes in the PT and MT Cobb angles were -0.33 and -0.34 degrees, respectively. The change in TL Cobb angle and coronal spinal balance were only measured in 29 patients with available spine radiographs. The median change in TL Cobb angle and coronal spinal balance were -0.69 degrees and 3.75 mm, respectively. The median preoperative and postoperative PT Cobb angles were 1.75 and 1.24 degrees. The difference between preoperative and postoperative PT Cobb angles was statistically insignificant (P=0.036). The median preoperative and postoperative MT Cobb angles were 1.32 and 1.09 degrees, respectively. The difference between preoperative and postoperative MT Cobb angles was statistically insignificant (P=0.221). Delayed breast reconstruction did not result in clinically significant improvement in mastectomy-induced spinal deformity. This finding should be considered when choosing between immediate and delayed breast reconstruction.

Prospective Follow-up Report on Anterior Vertebral Body Tethering for Idiopathic Scoliosis: Interim Results from an FDA IDE Study.

Anterior vertebral body tethering (aVBT) has emerged as a novel treatment option for patients with idiopathic scoliosis. We present the results from the first U.S. Food and Drug Administration (FDA) Investigational Device Exemption (IDE) study on aVBT. In this prospective review of a retrospective data set, eligible patients underwent aVBT at a single center from August 2011 to July 2015. Inclusion criteria included skeletally immature patients with Lenke type-1A or 1B curves between 30° and 65°. Clinical and radiographic parameters were collected, with the latter measured by an independent reviewer. Fifty-seven patients (49 girls and 8 boys), with a mean age (and standard deviation) of 12.4 ± 1.3 years (range, 10.1 to 15.0 years), were enrolled in the study. The patients had a mean of 7.5 ± 0.6 levels tethered, the mean operative time was 223 ± 79 minutes, and the mean estimated blood loss was 106 ± 86 mL. The patients were followed for an average of 55.2 ± 12.5 months and had a mean Risser grade of 4.2 ± 0.9 at the time of the latest follow-up. The main thoracic Cobb angle was a mean of 40.4° ± 6.8° preoperatively and was corrected to 18.7° ± 13.4° at the most recent follow-up. In the sagittal plane, T5-T12 kyphosis measured 15.5° ± 10.0° preoperatively, 17.0° ± 10.1° postoperatively, and 19.6° ± 12.7° at the most recent follow-up. Eighty percent of patients had curves of <30° at the most recent follow-up. The most recent Scoliosis Research Society (SRS) scores averaged 4.5 ± 0.4, and scores on the self-image questionnaire averaged 4.4 ± 0.7. No major neurologic or pulmonary complications occurred. Seven (12.3%) of 57 patients had a revision: 5 were done for overcorrection and 2, for adding-on. Anterior VBT is a promising technique that has emerged as a treatment option for patients with immature idiopathic scoliosis. We present the results from the first FDA-approved IDE study on aVBT, which formed the basis for the eventual Humanitarian Device Exemption approval. The findings affirm the safety and efficacy of this technique and suggest opportunities for improvement, particularly with respect to reoperation rates. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Investigation of in vivo three-dimensional changes of the spinal canal after corrective surgeries of the idiopathic scoliosis.

ObjectiveTo determine the three‐dimensional (3D) changes of the spinal canal length (SCL) after corrective surgeries and their association with the radiographic and clinical outcomes of idiopathic scoliosis patients. The length of the spinal cord has been demonstrated to be strongly correlated with the SCL. Understanding the changes in SCL could help determine the morphologic changes in the spinal cord to prevent spinal cord injury.MethodsTwenty‐seven scoliotic patients' 3D spinal canal were investigated using computed tomography images. The SCL between the upper and lower end vertebrae (U/L‐EV) was measured at five locations. The radiographic parameters of each patient and the patient‐reported outcomes (PROs) scores were also collected. The correlations of the changes of the SCLs with the other factors were analyzed.ResultsThe SCL between the U/L‐EV changed non‐uniformly at different locations. The post‐operative SCLs were significantly elongated by 7.5 ± 3.5 mm (6.0 ± 2.5%, P < .001) at the concave side and compressed by −2.6 ± 2.6 mm (−1.9 ± 1.9%, P < .001) at the convex side. The elongations of the SCL at the concave and posterior locations were correlated with the radiographic parameters including the pre‐operative main Cobb angles (r = .511, P = .006; r = .613, P = .001) and apical vertebral translation (AVT) (r = .481, P = .011; r = .684, P = .000). No PRO scores were found to correlate with the SCL changes.ConclusionThe corrective surgeries elongated the spinal canal mainly at the concave side and compressed at the convex side. The main thoracic Cobb angle, the changes of AVT, and Cobb angles were moderately associated with the changes of the SCLs, but no PRO score was found to associate with the changes of the SCLs. The data could be instrumental for the improvement of corrective surgeries that are aimed to maximize the correction of scoliosis and minimize the negative effect on the spinal cord to prevent neurological complications.