Preoperative low Hounsfield units in the lumbar spine are associated with postoperative mechanical complications in adult spinal deformity.

PURPOSE: To determine the most valid bone health parameter to predict mechanical complications (MCs) following surgery for adult spinal deformity (ASD). METHODS: This multicenter study retrospectively examined the records of patients who had undergone fusion of three or more motion segments, including the pelvis, with a minimum two-year follow-up period. Patients with moderate and severe global alignment and proportion scores were included in the study and divided into two groups: those who developed MCs and those who did not. Bone mineral density (BMD) of the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry, and Hounsfield units (HUs) were measured in the lumbar spine on computed tomography. Radiographic parameters were evaluated preoperatively, immediately after surgery, and at final follow-up. RESULTS: Of 108 patients, 30 (27.8%) developed MCs, including 26 cases of proximal junctional kyphosis/failure, 2 of distal junctional failure, 6 of rod fracture, and 11 reoperations. HUs were significantly lower in patients who experienced MCs (113.7 ± 41.1) than in those who did not (137.0 ± 46.8; P = 0.02). BMD did not differ significantly between the two groups. The preoperative and two-year postoperative global tilt, as well as the immediately postoperative sagittal vertical axis, were significantly greater in patients who developed MCs than in those who did not (P = 0.02, P < 0.01, and P = 0.01, respectively). CONCLUSION: Patients who experienced MCs following surgery for ASD had lower HUs than those who did not. HUs may therefore be more useful than BMD for predicting MCs following surgery for ASD.

Rod fracture after multiple-rod technique for adult spinal deformity: a case report.

Here we report the case of a 71-year-old woman who complained of lower back and left leg pain due to rod fracture following instrumented fusion using the lateral lumbar interbody fusion and multi-rod technique to treat adult spinal deformity. Radiographic images revealed bilateral rod fractures at L4-5 and pseudoarthrosis at L2-5; lower lumbar lordosis was minimal, but upper lumbar hyperlordosis was noted. The patient underwent revision surgery, which included posterior spinal instrument replacement, L3-4 and L4-5 lateral lumbar interbody fusion cage removal, and L4 vertebral body replacement via the anterior approach. This is a rare case of reoperation with the multi-rod technique. Revision surgery should be performed in consideration of the proportion of lumbar lordosis and anterior bony fusion as the posterior component is resected and bony fusion can only be achieved anteriorly.

Instrumentation failure following pediatric spine deformity growth-sparing surgery using traditional growing rods or vertical expandable prosthetic titanium ribs.

BACKGROUND: Instrumentation failure (IF) is a major complication associated with growth-sparing surgery for pediatric spinal deformities; however, studies focusing on IF following each surgical procedure are lacking. We aimed to evaluate the incidence, timing, and rates of unplanned return to the operating room (UPROR) associated with IF following each surgical procedure in growth-sparing surgeries using traditional growing rods (TGRs) and vertical expandable prosthetic titanium ribs (VEPTRs). METHODS: We reviewed 1,139 surgical procedures documented in a Japanese multicenter database from 2015 to 2017. Of these, 544 TGR and 455 VEPTR procedures were included for evaluation on a per-surgery basis. IF was defined as the occurrence of an implant-related complication requiring revision surgery. RESULTS: The surgery-based incidences of IF requiring revision surgery in the TGR and VEPTR groups were 4.3% and 4.0%, respectively, with no significant intergroup difference. Remarkably, there was a negative correlation between IF incidence per surgical procedure and the number of lengthening surgeries in both groups. In addition, rod breakage in the TGR group and anchor-related complications in the VEPTR group tended to occur relatively early in the treatment course. The surgery-based rates of UPROR due to IF in the TGR and VEPTR groups were 2.0% and 1.5%, respectively, showing no statistically significant difference. CONCLUSIONS: We found that IF, such as anchor related-complications and rod breakage, occurs more frequently earlier in the course of lengthening surgeries. This finding may help in patient counseling and highlights the importance of close postoperative follow-up to detect IF and improve outcomes.

Wedge-Shaped Deformity of the First Sacral Vertebra Associated with Adolescent Idiopathic Scoliosis: A Comparison of Cases with and without Scoliosis.

Introduction: Scoliosis is the three-dimensional (3D) deformity of the spine. Scoliosis curvatures, such as the lower lumbar curve and the angle of the upper endplate of the sacrum observable on radiographs, are associated with postoperative outcomes; however, the relationship between postoperative outcomes and sacral morphology remains unknown. This study aimed to investigate sacral morphology in patients with adolescent idiopathic scoliosis (AIS) and to clarify its relationship with wedge-shaped deformity of the first sacral vertebra and radiographic parameters. Methods: This study included 94 patients who underwent fusion surgery for AIS (scoliosis group). As the control group, 25 patients without scoliosis (<10°) under 50 years of age were also investigated. S1 wedging angle (S1WA) using 3D Computed tomography (CT) and Cobb angle, L4 tilt, and sacral slanting using radiography were measured. The relationship between S1WA and other radiographic parameters was analyzed using correlation coefficients. Differences in sacral morphology between the Lenke lumbar modifier types A and C were also investigated. Results: S1WA was significantly larger in the scoliosis group than the control group (scoliosis: 1.7°±2.5°, control: 0.1°±1.5°, p=0.002). Furthermore, the number of patients with S1WA >3° or >5° was significantly higher in the scoliosis group (>3°: 33%, 8%, p=0.012; >5°: 16%, 0%, p=0.039). S1WA correlated with sacral slanting (r=0.45, p<0.001) and L4 tilt (r=0.35, p<0.001) and was significantly greater with Lenke lumbar modifier C than A (2.4°±2.6°, 0.8°±2.0°; p<0.001). Conclusions: The S1 vertebra was deformed and wedge-shaped in AIS, especially in cases with a large lumbar curve. Additionally, S1WA is associated with sacral slanting and L4 tilt on radiography in AIS.

Relationship between lumbosacral transitional vertebra and postoperative outcomes of patients with Lenke 5C adolescent idiopathic scoliosis: a minimum 5-year follow-up study.

PURPOSE: To assess the incidence of lumbosacral transitional vertebra (LSTV) in Lenke 5C adolescent idiopathic scoliosis (AIS) and evaluate the relationship between postoperative outcomes and LSTV when the lowest instrumented vertebra (LIV) is fixed at L3. METHODS: The study included 61 patients with Lenke 5C AIS who underwent fusion surgery of L3 as the LIV who were followed-up for a minimum of 5 years. Patients were divided into two groups: LSTV + and LSTV-. Demographic, surgical, and radiographic data, including L4 tilt and thoracolumbar/lumbar (TL/L) Cobb angle, were obtained and analyzed. RESULTS: LSTV was observed in 15 patients (24.5%). The L4 tilt was not significantly different between the two groups preoperatively (P = 0.54); however, it was significantly greater in the LSTV group postoperatively (2 weeks: LSTV + = 11.7 ± 3.1, LSTV - = 8.8 ± 3.2, P = 0.013; 2 years: LSTV + = 11.5 ± 3.5, LSTV - = 7.9 ± 4.1, P = 0.006; 5 years: LSTV + = 9.8 ± 3.1, LSTV - = 7.3 ± 4.5, P= 0.042). The postoperative TL/L curve was greater in the LSTV + group, with significant differences at 2 weeks and 2 years postoperatively (preoperative: LSTV + = 53.5 ± 11.2, LSTV - = 51.7 ± 10.3,P = 0.675; 2 weeks: LSTV + = 16.1 ± 5.0, LSTV- = 12.2 ± 6.6, P = 0.027; 2 years: LSTV + = 21.7 ± 5.9, LSTV - = 17.6 ± 5.9, P = 0.035; 5 years: LSTV + = 18.7 ± 5.8, LSTV - = 17.0 ± 6.1, P = 0.205). CONCLUSION: The prevalence of LSTV in Lenke 5C AIS patients was 24.5%. Lenke 5C AIS patients with LSTV with the LIV at L3 had a significantly greater postoperative L4 tilt than those without LSTV and retained the TL/L curve.

Incidence and causes of instrument-related complications after primary definitive fusion for pediatric spine deformity.

OBJECTIVE: Various complications have been reported in the treatment of pediatric spinal deformities. Among these, instrument-related complications could be critical concerns and risks of reoperation. This study aimed to identify the incidence and causes of complications after primary definitive fusion for pediatric spine deformities. METHODS: The authors retrospectively collected data from 14 institutions about patients who underwent primary definitive fusion between 2015 and 2017. There were 1490 eligible patients (1184 female and 306 male), with a mean age of 13.9 years. The incidence, causes, and reoperation rates were analyzed according to 4 etiologies of pediatric spine deformity (congenital, neuromuscular, syndromic, idiopathic). The complications were also categorized as screw-, hook-, or rod-related complications, implant loosening or backout, and junctional problems. RESULTS: The incidence of overall instrument-related complications was 5.6% (84 cases). Regarding etiology, the incidence rates were 4.3% (idiopathic), 6.8% (syndromic), 7.9% (congenital), and 10.4% (neuromuscular) (p < 0.05). The most common causes were pedicle screw malposition (60.7%), followed by implant backout or loosening (15.4%), junctional problems (13.1%), rod breakage (4.8%), and other complications (6.0%). Univariate analysis showed that etiology, type of deformity (kyphosis), surgical procedure, operation time, and estimated blood loss were significant factors. Multivariate analysis revealed that etiology (neuromuscular), surgical procedure (combined approach), and operation time (> 5 hours) remained as significant risk factors. Among all patients with instrument-related complications, 45% (38/84) required revision surgery. Of these cases, > 50% were related to pedicle screw malposition. Medial breach was the most common complication regardless of location, from upper thoracic to lumbar spine. CONCLUSIONS: Pedicle screw malposition was the primary cause of overall complications and subsequent reoperation. In addition to more precise screw insertion techniques, meticulous confirmation of pedicle screw placement, especially of medial breach, may reduce the overall instrument-related complications and revision rates.

Cervical Spinal Cord Compression in Adult Scoliosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The aim was to examine cervical spinal cord compression (SCC) in adult scoliosis and clarify the prevalence of and risk factors for cervical SCC. METHODS: This study included 270 adult scoliosis patients and 1211 healthy volunteers. Cervical SCC was evaluated on cervical magnetic resonance imaging (MRI). The rates of SCC for those with adult scoliosis and the healthy volunteers were compared. Logistic regression analysis was conducted to examine the factors associated with cervical SCC on MRI. RESULTS: In cases with adult scoliosis, preoperative major scoliosis curve was 56.0° ± 18.8°, and cervical SCC was detected in 25 patients (9.3%). Among the healthy volunteers, 64 cases with cervical SCC were detected. Only in cases with adult scoliosis, logistic regression analysis revealed higher age (OR 1.09, 95% CI 1.04-1.14, P < .001), narrow canal diameter (OR 2.27, 95% CI 1.35-3.85, P = .002), and inferior sagittal balance (OR 2.45, 95% CI 1.02-5.89, P = .04) as significant risk factors. In the logistic regression analysis in all subjects (including adult scoliosis and healthy volunteers), higher age (OR 1.08, 95% CI 1.06-1.10, P < .001) and narrow canal diameter (OR 1.62, 95% CI 1.37-1.92, P < .001) were also found to be significant risk factors, but the presence of scoliosis was not a significant factor. CONCLUSIONS: Adult scoliosis itself was not significantly associated with cervical SCC. Inferior sagittal balance in addition to scoliosis constituted a significant risk factor for cervical SCC.

Trends in the numbers of spine surgeries and spine surgeons over the past 15 years.

The purpose of this study is to examine trends in spine surgeries at ten facilities over 15 years, and to analyze relationships with the number of spine surgeons at these facilities. The subjects were patients who underwent spine surgery at the ten facilities from 2003 to 2017. Data were collected every year via a questionnaire designed to obtain clinicopathological and surgical information. There were 37,601 spine surgeries (60.2% male) recorded in the registry at 9 facilities in the Nagoya Spine Group (NSG) between 2003 and 2017, with an increase in the annual number of surgeries by 2.4 times over 15 years. On the other hand, the number of spine surgeons has increased by just under 1.5 times. Instrumentation surgeries increased from 959 in 2003 to 2,276 in 2017 (2.3 times). There was a particularly marked increase in surgeries for spinal degenerative disease from 1,075 in 2003 to 2,821 in 2017 (2.6 times). The number of surgeries performed per surgeon increased from 61.4 in 2003 to 102.8 in 2017, while the average number of spine surgeons per hospital increased from 2.6 in 2003 to 3.7 in 2017. In conclusion, with heavier burden on spine surgeons and the major changes in the spine surgery environment, training and increasing surgeons with advanced expertise and skills will become increasingly important.

Factors affecting postoperative pulmonary function deterioration in adolescent idiopathic scoliosis: A prospective study using 3-dimensional image reconstruction by biplanar stereoradiography.

This study aimed both to evaluate rib cage parameters in patients with adolescent idiopathic scoliosis (AIS) by three-dimensional (3D) image reconstruction using biplanar stereoradiography (EOS) (EOS Imaging, Paris, France) and identify factors associated with postoperative pulmonary function deterioration (PFD). A total of 67 patients with Lenke type 1 or 2 AIS (59 females and 8 males; mean age, 14.4 years) undergoing posterior corrective fusion with a rod rotation maneuver based on segmental pedicle screw fixation were recruited. 3D images and pulmonary function test results were analyzed preoperatively and at 2 years postoperatively. The following parameters were measured: maximum thickness, maximum width, thoracic index, rib hump, rib cage volume (RCV), spinal penetration index (SPI), endothoracic hump ratio (EHR), vertebra-sternum angle (VSA), rib-vertebra angle difference, vertebral lateral decentering (VLD), forced vital capacity (FVC), and percent predicted FVC (%FVC). PFD was defined as a postoperative %FVC decline of 5% or greater. Patients were divided into two groups, namely PFD and non-PFD. FVC increased from 2.62 L to 2.73 L, while %FVC decreased from 88.7% to 82.7%. The maximum width diminished postoperatively in the PFD group. Patients in the PFD group exhibited a significantly smaller increase in RCV and VLD as well as a significantly smaller decrease in SPI, EHR, and VSA than those in the non-PFD group. The rib cage parameters quantified on 3D images reconstructed using EOS are useful in identifying factors affecting PFD in patients with AIS.

Does pulmonary function improve after surgical correction of adult idiopathic scoliosis?

PURPOSE: The aim was to investigate pulmonary function after surgical correction of adult idiopathic scoliosis. METHODS: This study included 146 adult scoliosis patients aged 20-50 years (main curve in thoracic spine). Respiratory function was assessed as predicted forced vital capacity (%FVC) and the ratio of forced expiratory volume in 1 s / FVC (%FEV1) preoperatively and 2 years postoperatively and classified as a normal function (≥ 80%), mild impairment (≥ 65% and < 80%), and moderate impairment (< 65%). RESULTS: Preoperative %FVC and %FEV1 were 85.3% and 85.4%, which were 81.5% and 87.5% at 2 years post-surgery. The preoperative %FVC was mild and moderate in 39 (26.7%) and 12 patients (11.6%), respectively. The %FVC significantly improved (+ 6.2% ± 11.4%, P < 0.001) postoperatively for moderate severity but significantly decreased postoperatively (- 6.4% ± 9.4%, P < 0.001) for normal function. The preoperative %FEV1 was mild and moderate in 27 (18.5%) and 0 patients, respectively. The %FEV1 significantly improved postoperatively (6.3% ± 5.3%, P < 0.001) for mild severity but did not significantly change for normal severity. Twenty-three (15.8%) and 41 (28.1%) patients showed improved ⊿%FVC and ⊿% FEV1 > 5%. Logistic regression analysis showed that preoperative %FVC and %FEV1 severities were independent factors affecting postoperative recovery of %FVC (OR 0.95) and %FEV1 (OR 0.85). CONCLUSION: Pulmonary function improved in patients with preoperative pulmonary impairment of < 65% in %FVC and < 80% in %FEV1, and the real improvement was limited to patients with severe preoperative impairment.

Three-dimensional reconstruction image by biplanar stereoradiography reflects pulmonary functional states inadolescent idiopathic scoliosis.

This study investigated whether the rib cage parameters estimated based on reconstructed three-dimensional (3D) images with biplanar stereoradiography reflect pulmonary functional states in adolescent idiopathic scoliosis (AIS) patients. A total of 67 Lenke type 1 or 2 AIS patients (59 females and 8 males, mean age 14.4 years) were enrolled. All patients underwent preoperative pulmonary functional tests (PFT) and biplanar stereoradiography. Vital capacity (VC) and forced vital capacity (FVC) pulmonary functional data were collected. Rib-cage parameters (maximum thickness, maximum width, thoracic index (TI), rib hump (RH), rib-cage volume (RCV), spinal penetration index (SPI), endothoracic hump ratio (EHR), vertebra-sternum angle (VSA), rib vertebral angle difference (RVAD), and vertebral lateral decentering (VLD)) were quantified from 3D images. Patients were divided into two groups: restrictive lung disorder (RLD) (%FVC < 80%) and non-RLD (%FVC ≥ 80%). The maximum width and RCV were significantly correlated with VC (p < 0.0001), and FVC (p < 0.0001). RH, EHR, and VSA were negatively correlated with %FVC (p < 0.01). TI, SPI, and RVAD were not correlated with any pulmonary parameters. The maximum widths of RLD patients were significantly shorter than those of the non-RLD patients (218.3 mm vs. 229.7 mm, p < 0.01). The RCV of RLD patients was significantly smaller than that of the non-RLD patients (3.94 L vs. 4.49 L, p < 0.0001). The maximum width and RCV measured by 3D images with biplanar stereoradiography reflected pulmonary functional variables in patients with AIS.

Surgical Site Infection Following Primary Definitive Fusion for Pediatric Spinal Deformity: A Multicenter Study of Rates, Risk Factors, and Pathogens.

STUDY DESIGN: A retrospective multicenter study. OBJECTIVE: To determine the surgical site infection (SSI) rate, associated risk factors, and causative pathogens in pediatric patients with spinal deformity. SUMMARY OF BACKGROUND DATA: There have been no extensive investigations of the risk factors for SSI in Japan. METHODS: Demographic data, radiographic findings, and the incidence of SSI were retrospectively analyzed in 1449 pediatric patients who underwent primary definitive fusion surgery for spinal deformity at any of 15 institutions from 2015 to 2017. SSI was defined according to the US Centers for Disease Control and Prevention guideline. RESULTS: The incidence of all SSIs was 1.4% and that of deep SSIs was 0.76%. The most common pathogenic microbes were methicillin-resistant staphylococci (n = 5) followed by gram-negative rods (n = 4), methicillin-sensitive staphylococci (n = 1), and others (n = 10). In univariate analysis, younger age, male sex, a diagnosis of kyphosis, type of scoliosis, American Society of Anesthesiologists (ASA) class ≥3, mental retardation urinary incontinence, combined anterior-posterior fusion, greater magnitude of kyphosis, three-column osteotomy, use of blood transfusion, and number of antibiotic administration were associated with the likelihood of SSI (all P < 0.05). Multivariate logistic regression analysis identified the following independent risk factors for SSI: syndromic scoliosis etiology (vs. idiopathic scoliosis; adjusted odds ratio [OR] 16.106; 95% confidence interval [CI] 2.225-116.602), neuromuscular scoliosis etiology (vs. idiopathic scoliosis; adjusted OR 11.814; 95% CI 1.109-125.805), ASA class 3 (vs. class 2; adjusted OR 15.231; 95% CI 1.201-193.178), and administration of antibiotic therapy twice daily (vs. three times daily; adjusted OR 6.121; 95% CI 1.261-29.718). CONCLUSION: The overall infection rate was low. The most common causative bacteria were methicillin-resistant followed by gram-negative rods. Independent risk factors for SSI in pediatric patients undergoing spinal deformity surgery were scoliosis etiology, ASA class 3, and administration of antibiotic therapy twice daily.Level of Evidence: 3.

Increase in dural ectasia size in scoliosis patients with Marfan syndrome.

Increased dural ectasia and vertebral thinning in the lumbosacral spine are common in Marfan syndrome. Dural ectasia is unchanged in middle-aged patients, who have stopped growing. Therefore, evaluation from childhood to adulthood is mandatory. Sixteen patients [four men and 12 women; mean age:17.7 (8.6-33.5) years] with dural ectasia at final follow-up [mean follow-up: 10.4 (5.0-16.7) years] were enrolled. Dural sac diameter (DD)/vertebral diameter (VD) were measured on MRI or CT images of midline sagittal slices at the level of dural ectasia between L5 and S3. The widest part of the dural sac was evaluated with Fattori grading: grade 0, normal; 1, mild; 2, moderate; and 3, severe dural ectasia. At final follow-up, dural ectasia was observed at L5 in 3, S1 in 9, S2 in 14, and S3 in 11 patients. Respective changes in DD/VD from primary to final follow-up were L5: 21.7-24.2 mm/29.1-27.9 mm; S1: 17.0-18.6 mm/21.0-19.5 mm; S2: 15.5-19.6 mm (P < 0.01)/9.6-7.5 mm; and S3: 15.6-17.9 mm (P < 0.05)/6.2-3.3 mm (P < 0.05). Four patients had grade 0 dural ectasia, seven had grade 1, two had grade 2, and three had grade 3. Grade was increased in nine patients with juvenile to young adult patients but did not with adults. During follow-up, dural ectasia size changed in the juvenile to young adult patients with Marfan syndrome, particularly at the S2-S3 level in our series.

Incidence and Risk Factors for Unplanned Return to the Operating Room Following Primary Definitive Fusion for Pediatric Spinal Deformity: A Multicenter Study with Minimum 2-year Follow-Up.

STUDY DESIGN: A retrospective multicenter cohort study. OBJECTIVE: The aim of this study was to identify the incidence and risk factors for UPROR within minimum 2-year follow-up in primary definitive fusion for pediatric spinal deformity. SUMMARY OF BACKGROUND DATA: Several previous reports have elucidated the incidence of complications after pediatric scoliosis surgery; however, there has been no study that described the incidence and risk factors for unplanned return to the operating room (UPROR) with long-term follow-up in surgery for pediatric scoliosis with every etiology. METHODS: We retrospectively extracted data of patients aged <19 years, from 14 institutes in Japan, who underwent primary definitive fusion surgery for spinal deformity between January 1, 2015 and December 31, 2017. The primary outcomes were the incidence of UPROR within the minimum 2-year follow-up period for any reason. Univariate and multivariate logistical analyses were conducted to identify potential risk factors associated with UPROR. RESULTS: We identified 1417 eligible patients (287 males and 1130 females) with a mean age of 13.9 years. UPROR for any reason within minimum 2-year follow-up was identified in 68 patients (4.8%). The most frequent cause for UPROR was implant failure found in 29 patients, followed by surgical site infection in 14 patients, junctional problems in 10 patients, and neurological complications in six patients. The multivariate logistic regression analysis revealed that a diagnosis of kyphosis (odds ratio [OR], 2.65; 95% confidence interval [CI] 1.16-6.04), etiology of congenital or structural type (OR 2.21; 95% CI 1.08-4.53), etiology of syndromic type (OR 2.67; 95% CI 1.27-5.64), and increased operation time of ≥300 minutes (OR 1.81; 95% CI 1.07-3.07) were the risk factors for the incidence of UPROR. CONCLUSION: The present multicenter study identified for the first time the incidence and risk factors for UPROR with minimum 2-year follow-up after primary definitive fusion surgery for pediatric spinal deformity with every etiology.Level of Evidence: 3.

A New Global Spinal Balance Classification Based on Individual Pelvic Anatomical Measurements in Patients With Adult Spinal Deformity.

STUDY DESIGN: A retrospective study. OBJECTIVE: This study aims to establish a new, easy-to-implement global spinal balance (GSB) classification based on individual pelvic anatomical measurements in adult spinal deformity patients, and to validate this classification in terms of patients' quality of life (QOL). SUMMARY OF BACKGROUND DATA: Coronal (central sacral vertical line) and sagittal (C7 sagittal vertical axis [C7 SVA]) lines are standard parameters to evaluate GSB. However, these parameters do not consider individual differences in height and physique. Therefore, a new classification to more simply evaluate GSB related to QOL would be a beneficial tool. METHODS: This study included 279 patients with adult spinal deformity. The enrollment criteria included age >18 years and scoliosis >30°. GSB was evaluated based on C7 coronal vertical axis and C7 SVA, and was graded with our sagittal (Grades 1-3) and coronal classifications (Grades 1-3), where larger values represented worse GSB. In addition, total global balance classification (Grades 1-3) was also established based on both coronal and sagittal classifications. Patient self-assessment measures of health status were collected using the Scoliosis Research Society patient questionnaire (SRS-22). The relationships between responses to the SRS-22 and GSB were evaluated using partial correlation coefficients, adjusted by age. RESULTS: A newly described coronal classification correlated with the preoperative function (P < 0.02), pain (P = 0.001), subtotal (P < 0.001) domains in the SRS-22, whereas a newly described sagittal classification was correlated with the preoperative subtotal domain (P < 0.001). There were also significant correlations between total global balance and the preoperative function (P = 0.03) and subtotal domains (P < 0.001) in the SRS-22. CONCLUSION: We present a simple new classification for GSB that strongly correlates with QOL in patients with adult spinal deformity, thereby translating clinical data into meaningful patient outcomes and livelihoods.Level of Evidence: 4.

Three-Dimensional Analysis of Preoperative and Postoperative Rib Cage Parameters by Simultaneous Biplanar Radiographic Scanning Technique in Adolescent Idiopathic Scoliosis: Minimum 2-Year Follow-Up.

STUDY DESIGN: Prospective study. OBJECTIVE: This study aimed to investigate the changes in rib cage deformity in adolescent idiopathic scoliosis (AIS) by comparing the preoperative and postoperative three-dimensional (3D) reconstruction images using simultaneous biplanar radiographic scanning technique (EOS) (EOS Imaging, Paris, France). SUMMARY OF BACKGROUND DATA: EOS data are limited for the analyses of preoperative and postoperative rib cage deformity. METHODS: A total of 67 Lenke type 1 or 2 AIS patients who underwent surgery (59 females and 8 males) were enrolled in this study. The mean patient age was 14.4 years (range: 11-17 yr). In all patients, posterior corrective fusion was performed with a rod rotation maneuver based on segmental pedicle fixation. Spinal parameters (scoliosis and kyphosis) and rib cage parameters (max thickness, thoracic index (TI), rib hump (RH), surface spinal penetration index (sSPI), end thoracic hump ratio, vertebra-sternum angle, rib vertebral angle difference at the apex, and vertebral lateral decentering), were measured. 3D images were assessed preoperatively and postoperatively at 2-year follow-up. RESULTS: Both main thoracic (MT) and proximal thoracic scoliosis were significantly corrected (51° to 15°, 30° to 17°, P < 0.0001). The rotation of MT apical vertebrae was also significantly corrected (12° to 5°, P < 0.0001). Thoracic kyphosis (T4-T12) significantly increased (13° to 18°, P < 0.0001). Besides, max thickness, TI, and RH demonstrated significant differences between preoperative and postoperative images (P < 0.01). T8-10 sSPI and end thoracic hump ratio decreased significantly postoperatively (P < 0.05). Although surgery significantly decreased vertebra-sternum angle (P < 0.0001), no significant difference was observed between the preoperative and postoperative rib vertebral angle difference (P = 0.32). Following the surgery, vertebral lateral decentering and rib cage volume were significantly increased (P < 0.0001). CONCLUSIONS: 3D reconstruction of the rib cage using biplanar standing stereoradiography is useful to evaluate preoperative and postoperative rib cage deformity in patients with AIS.Level of Evidence: 2.

Impact of Rigid Fixation of the Pubic Symphysis for Spinopelvic Fixation in Two Cases of Lumbosacral Agenesis.

INTRODUCTION: In patients with lumbosacral agenesis (SA), Renshaw type III or IV, lumbosacral instability is the primary cause of major clinical complications. Although they are usually treated with spinopelvic fusion, nonunion at the spinopelvic junction is a major complication due to the congenital sacropelvic abnormalities. The purpose of this study was to evaluate whether a combination of lumbosacral fixation and rigid fixation at the pubic symphysis could lead to postoperative bone union in patients with SA (Renshaw type III). METHODS: Retrospective case series study. We present the cases of two patients with SA, Renshaw type III, who were surgically treated by lumbosacral fusion using a posterior approach, and they exhibited nonunion at the lumbosacral junction. RESULTS: Case 1. A 10-year-old male underwent T8-S posterior fixation followed by multiple augmentations using allografts at the lumbosacral junction for delayed union. All additional procedures with bone graft using a posterior approach failed to achieve bone union; however, additional rigid fixation at the pubic symphysis resulted in a successful lumbosacral bone union. Case 2. A 6-year-old male underwent vertical expandable prosthetic titanium rib (VEPTR) surgery with multiple rod extension procedures. Subsequently, at the age of 10 years, a combined two-stage anterior (L1-3) and posterior (T8-iliac) fixation with T9 hemivertebrectomy was performed. As a result of subsequent nonunion with screw loosening, additional rigid fixation at the pubic symphysis was performed 1 month after posterior fixation. Bone union was finally achieved 1 year after all the surgical interventions. CONCLUSIONS: Rigid fixation at the pubic symphysis may play a significant role in achieving rigid bone union for unstable lumbopelvic connection, such as SA, Renshaw type III or IV.

Nonanesthetized Alternatively Repetitive Cast and Brace Treatment for Early-onset Scoliosis.

BACKGROUND: Use of cast is a standard treatment (Tx) choice for early-onset scoliosis. Recently, toxicity from repetitive use of general anesthesia has received attention by the Food and Drug Administration (FDA). We introduce a nonanesthetized cast Tx protocol called alternatively-repetitive-cast-and-brace (ARCB) that we have used since 1995 and have conducted an extensive follow-up on these patients to verify the efficacy of this protocol. STUDY DESIGN: This is a retrospective cohort study. METHODS: Of a consecutive series of 155 patients who have undergone cast Tx at a single institution, 98 patients (male: 36, female: 62) have been identified under the following criteria: (1) Initial age before ARCB of ≤6; (2) Follow-up period of ≥2 years; (3) Initial scoliosis ≥35 degrees. Patients consisted of the following: congenital/structural: 45, idiopathic: 23, neuromuscular: 6, syndromic: 24. Precast, postfinal cast, minimum in-cast Cobb, as well as thoracic and T1-S1 heights were measured. Fifty-six of these patients had available pulse oximetry on days before and after initial cast, and these were also evaluated to assess cardiopulmonary effects that the cast have on the patients. RESULTS: Patients were casted 6.6 times, with a mean initial Cobb of 56.5 degrees and a final follow-up Cobb of 57.1 degrees. Follow-up period was 5.0 years. Mean curve progression per follow-up period was 0.5 degrees/y. Minimum in-cast Cobb was 25.6 degrees. Initially patients had a thoracic and T1-S1 height of 12.6 and 22.5 cm, respectively. At final cast, these were 15.3 and 27.2 cm, respectively. Of these patients, 39 had progression >1 degree/y, of which 83.1% had resulted in surgical correction, while this was true for only 37.3% of those that did not show such progression. Idiopathic patients had the greatest correction rate by cast (69%) and had shown an overall progression rate of -2.3 degrees/y. Pulse-oximetry results were not significant amongst patients before and after cast placement. CONCLUSIONS: ARCB is a versatile and practical Tx choice. It is an effective delaying method in sparing time until surgery with no apparent cardiopulmonary compromise. Curve control was most effective in Idiopathic patients while some curve control was achieved in other etiologies which may have spared time until their eventual surgery. SIGNIFICANCE: Cast Tx without the need of general anesthesia is an increasingly important topic since anesthesia toxicity from its repetitive use has become apparent. This study exemplifies safe and efficacious use of such cast with effective suppression on cast progression in different etiologies at various degrees.