Tracheal stenosis due to cervicothoracic hyperlordosis in patients with cerebral palsy treated with posterior spinal fusion: a report of the first two cases.

BACKGROUND: Spinal deformity is frequently identified in patients with cerebral palsy (CP). As it progresses, tracheal stenosis often develops due to compression between the innominate artery and anteriorly deviated vertebrae at the apex of the cervicothoracic hyperlordosis. However, the treatment strategy for tracheal stenosis complicated by spinal deformity in patients with CP remains unknown. CASE PRESENTATION: This study reports two cases: a 19-year-old girl (case 1) and a 17-year-old girl (case 2), both with CP at Gross Motor Function Classification System V. Both patients experienced acute oxygen desaturation twice within the past year of their first visit to our department. X-ray and computed tomography revealed severe scoliosis and cervicothoracic hyperlordosis causing tracheal stenosis at T2 in case 1 and at T3-T4 in case 2, suggesting that their acute oxygen desaturation had been caused by impaired airway clearance due to tracheal stenosis. After preoperative halo traction for three weeks, both patients underwent posterior spinal fusion from C7 to L5 with Ponte osteotomy and sublaminar taping at the proximal thoracic region to correct cervicothoracic hyperlordosis and thoracolumbar scoliosis simultaneously. Postoperative X-ray and computed tomography revealed that the tracheal stenosis improved in parallel with the correction of cervicothoracic hyperlordosis. Case 1 did not develop respiratory failure 1.5 years after surgery. Case 2 required gastrostomy postoperatively due to severe aspiration pneumonia. However, she developed no respiratory failure related to impaired airway clearance at one-year follow-up. CONCLUSIONS: We present the first two cases of CP that developed tracheal stenosis caused by cervicothoracic hyperlordosis concomitant with progressive scoliosis and were successfully treated by posterior spinal fusion from C7 to L5. This enabled us to relieve tracheal stenosis and correct the spinal deformity at the same time. Surgeons must be aware of the possibility of coexisting tracheal stenosis in treating spinal deformity in patients with neurological impairment because the surgical strategy can vary in the presence of tracheal stenosis. This study demonstrated that some patients with CP with acquired tracheal stenosis can be treated with spinal surgery.

Excessive correction impacts postoperative shoulder imbalance in lenke type 5C adolescent idiopathic scoliosis.

BACKGROUND: Postoperative shoulder imbalance (PSI) has a negative impact on the surgical outcomes of patients with adolescent idiopathic scoliosis. This study aimed to evaluate the risk factors of PSI in patients with Lenke type 5C curves. METHODS: This study included 100 patients who underwent posterior correction surgery using pedicle screw constructs for Lenke type 5C curves. The mean age of the patients at surgery was 15.5 ± 2.3 years, and the mean follow-up period was 36.6 ± 15.0 months. The subjects were classified into the following two groups: PSI and non-PSI. Radiographic parameters, including the preoperative and 2-year postoperative coronal and sagittal profiles, were compared between the two groups. RESULT: PSI was found in eight patients (8.0%). The preoperative Cobb angles were 47.3° ± 8.7° and 48.0° ± 3.9° in the non-PSI and PSI groups, respectively. The correction rate in the PSI group was significantly higher than that in the non-PSI group (81.0% ± 17.7% vs. 67.7% ± 14.7%; p = 0.018). The preoperative T1 tilt angle in the PSI group was significantly larger than that in the non-PSI group (6.1° ± 3.3° vs. 3.1° ± 2.8°; p = 0.005). Receiver operating characteristic (ROC) analysis showed that the area under the ROC curve was 0.769 (p = 0.012, 95% confidence interval [CI], 0.556-0.982) and 0.763 (p = 0.014, 95% CI, 0.598-0.928) for the correction rate and preoperative T1 tilt, respectively. The cut-off value was 73% and 4° for the correction rate and preoperative T1, respectively. CONCLUSION: PSI was found in 8.0% of Lenke type 5C curves. Excessive correction of the lumbar curve of >73% and preoperative T1 tilt of >4° can be risk factors for PSI in patients with Lenke type 5C curve.

Evaluation of thoracic factors after scoliosis surgery in patients with both scoliosis and pectus excavatum.

PURPOSE: Pectus excavatum can negatively impact cardiac function during scoliosis surgery. Several authors reported severe hypotension associated with the prone position during scoliosis surgery in children that had both scoliosis and pectus excavatum. However, we could find no studies that evaluated the change in the thoracic factors, such as sternal tilt angle and Haller index after scoliosis surgery in patients with both scoliosis and pectus excavatum. The purpose of this study is to evaluate the change in thoracic factors after surgical treatment for scoliosis associated with pectus excavatum. METHODS: We performed a retrospective review on 20 patients (10 males and 10 females) who underwent surgical treatment for scoliosis associated with pectus excavatum from August 2004 to April 2014 in our hospital. We investigated the scoliosis diagnosis, preoperative and postoperative Cobb and thoracic kyphosis (TK) angles, the change in TK after surgery and thoracic factors, including the AP and transverse diameters of the chest, the sternal tilt angle, and Haller index. RESULTS: Patient mean age was 13.2 years old (4-27 years old) at surgery. Types of scoliosis were idiopathic in 8 patients, syndromic in 10, and neuromuscular in 2. The mean Cobb angles were 72.1° preoperatively and 19.0° postoperatively. Curve locations were thoracic in 13 patients, thoracolumbar in 4, and lumbar in 3. Surgical treatment of pectus excavatum was performed in 9 patients (45 %) before scoliosis treatment. Mean sternal tilt angles were 11.5° preoperatively and 11.1° postoperatively. Mean Haller indices were 4.8 preoperatively and 5.3 postoperatively. This was especially true for syndromic or neuromuscular scoliosis and thoracolumbar/lumbar curve type patients in which scoliosis surgery tended to worsen the Haller index. CONCLUSION: The Haller index increased postoperatively in 11 of 20 patients, which means sternal depression deteriorated after scoliosis surgery in about 50 % of patients. We suggest that surgeons fully assess the thoracic factors in patients with scoliosis and pectus excavatum prior to performing scoliosis surgery and carefully monitor their patient's general condition during surgery.

Three-Dimensional Analysis of Hemimetameric Segmental Shift in Congenital Scoliosis.

STUDY DESIGN: This is a retrospective cohort study. BACKGROUND: Hemimetameric segmental shift (HMMS) is defined as a hemivertebral deformation in which 2 or more hemivertebrae exist on both sides of the spine and are separated by at least 1 normal vertebra. Reports of HMMS are rare and based on simple anterior x-ray images. No reports have used 3-dimensional computed tomography (3D-CT) to analyze both the anterior and posterior elements. The objective of this study was to analyze the morphology and clinical features of HMMS 3 dimensionally. METHODS: HMMS was confirmed in 32 (6.6%, 16 males and 16 females) of 483 patients diagnosed with congenital scoliosis at the study institution between 1998 and 2013. The average age at the first visit was 6 years and 3 months. 3D-CT imaging was performed for 30 patients older than 2 years (average age: 9 y and 8 mo) and used to classify cases according to posterior elements. RESULTS: With regard to the number of hemivertebrae present, 21 patients had 2 hemivertebrae, 7 patients had 3 hemivertebrae, and 2 patients had 4 hemivertebrae. Patients with 2 hemivertebrae predominantly had hemivertebrae in the thoracolumbar spine. Patients were classified into 2 categories: malformation existing at an equal level in anterior and posterior sides (unison HMMS) and malformation existing at nonequal levels (discordant HMMS). Nine patients had unison HMMS and all of them had 2 hemivertebrae (average: 4.6 vertebrae). Twenty-one patients had discordant HMMS, with 12 having 2 hemivertebrae, 7 having 3 hemivertebrae, and 2 having 4 hemivertebrae. CONCLUSIONS: Through 3D-CT analysis, HMMS was categorized as unison or discordant. Discordant HMMS was observed in 21 of 30 (70%) patients and in all patients with >3 hemivertebrae. Diagnosing HMMS, whether unison or discordant, is clinically important and should be done with careful analysis of bone models and/or radiologic images to determine the correct spinal levels. LEVEL OF EVIDENCE: Level IV-diagnostic study.

Spinal fusion as a viable treatment option for scoliosis management in Pompe disease: a postoperative 3-year follow-up.

PURPOSE: This study presents 3-year postoperative outcomes of posterior spinal correction and fusion of a patient diagnosed with late-onset Pompe disease (PD) for his progressive scoliosis. METHODS: The patient was diagnosed for PD during his infancy. Enzyme replacement therapy (ERT) was initiated at the age of 13. First office visit for his spinal deformity was at the age of 15, and 40°, 34°, 6° spinal curvatures were seen in T6-L3, T1-6, and L3-S, respectively. Reduced pulmonary function, limited gait function and atrophied limb were documented. Initial brace treatment could not control curve progression; therefore, posterior spinal correction and fusion were performed at the age of 17. RESULTS: Immediate preoperative curves of 55°, 42° and 23° were corrected to 18°, 26° and 7° in T6-L2, T1-T6 and L2-S, respectively. Spinal fusion was performed from T3 to L4. The patient exhibited an excessively low pulmonary function preoperatively with a VC, FVC, and %VC of 1.45 L, 1.36 L, and 35 %, respectively. This has been managed with only moderate reductions despite reduced pulmonary function from PD throughout the operative period and at 3 years. At the final follow-up, VC, FVC and %VC were 1.33 L, 1.12 L and 28.5 %, respectively. CONCLUSION: Posterior spinal correction and fusion adequately controlled spinal curvatures for 3 years after surgery. Additionally, pulmonary function was managed throughout the follow-up period. Despite ERT, skeletal muscle and pulmonary function can still be severely affected by PD. Spinal correction and fusion is a useful method for the management of spinal curvature and pulmonary function in patients with PD.

Reliability analysis of Cobb angle measurements of congenital scoliosis using X-ray and 3D-CT images.

PURPOSE: Therapeutic decisions for congenital scoliosis rely on Cobb angle measurements on consecutive radiographs. There have been no studies documenting the variability of measuring the Cobb angle using 3D-CT images in children with congenital scoliosis. The purpose of this study was to compare the reliability and measurement errors using X-ray images and those utilizing 3D-CT images. MATERIALS AND METHODS: The X-ray and 3D-CT images of 20 patients diagnosed with congenital scoliosis were used to assess the reliability of the digital 3D-CT images for the measurement of the Cobb angle. Thirteen observers performed the measurements, and each image was analyzed by each observer twice with a minimum interval of 1 week between measurements. The analysis of intraobserver variation was expressed as the mean absolute difference (MAD) and standard deviation (SD) between measurements and the intraclass correlation coefficient (IaCC) of the measurements. In addition, the interobserver variation was expressed as the MAD and interclass correlation coefficient (IeCC). RESULTS: The average MAD and SD was 4.5° and 3.2° by the X-ray method and 3.7° and 2.6° by the 3D-CT method. The intraobserver and interobserver intraclass ICCs were excellent in both methods (X-ray: IaCC 0.835-0.994 IeCC 0.847, 3D-CT: IaCC 0.819-0.996 IeCC 0.893). There was no significant MAD difference between X-ray and 3D-CT images in measuring each type of congenital scoliosis by each observer. CONCLUSIONS: Results of Cobb angle measurements in patients with congenital scoliosis using X-ray images in the frontal plane could be reproduced with almost the same measurement variance (3°-4° measurement error) using 3D-CT images. This suggests that X-ray images are clinically useful for assessing any type of congenital scoliosis about measuring the Cobb angle alone. However, since 3D-CT can provide more detailed images of the anterior and posterior components of malformed vertebrae, the volume of information that can be obtained by evaluating them has contributed greatly to the development of strategies for the surgical treatment of congenital scoliosis.

Medially misplaced pedicle screws in patients without neurological deficits following scoliosis surgery: to observe or to remove?

PURPOSE: This study investigated whether pedicle screws medially misplaced into the spinal canal without neurological complications should be removed or not. METHODS: A total of 86 patients with scoliosis that underwent spinal fusion using 988 pedicle screws were retrospectively reviewed after a minimum follow-up of 2 years. The inclusion criteria were: (1) patients without outstanding problems during the insertion of pedicle screws, (2) patients without neurological deficits either intraoperatively or postoperatively, and (3) patients that had all implants removed after bone union upon the request of the patient. Medial perforations were evaluated using immediate postoperative helical CT images and classified into three grades: grade 1 (0-2 mm), grade 2 (2-4 mm), and grade 3 (over 4 mm). All unexpected events were recorded at the time of removal. RESULTS: CT images obtained 2 years postoperatively exhibited neither loosening of screws nor pseudoarthrosis in all patients. CSF leakage from screw holes were recognized in 3 of 87 medially misplaced screws (3.4 %). There was no CSF leakage in grade 1 (35 screws), one CSF leakage (2.5 %) in grade 2 (40 screws), and two (16.7 %) in grade 3 (12 screws). No neurological abnormalities occurred either intraoperatively or postoperatively. CONCLUSION: This study indicated that screws medially misplaced at a distance greater than 2 mm, especially 4 mm, may be a cause of negative effects on the neural structure and should be removed during the early phase of the postoperative period, even among patients without postoperative neurological abnormalities.

Reconstructive surgery for the post-hemiepiphysiodesis residual deformity in congenital scoliosis.

Spinal hemiepiphysiodesis is a well-known surgical procedure for correcting angular deformity in which the anterior and/or posterior epiphyseal plates of several vertebrae are fused on the convex side of the curvature with the expectation of spontaneous correction through continued growth of the concave side. We report on a patient with congenital scoliosis that had problems after hemiepiphysiodesis and required a salvage, reconstructive, antero-posterior combined surgery with instrumentation and osteotomy. After hemiepiphysiodesis, a marked fusion mass and a loss of bony landmarks made osteotomy and correction with a salvage surgery extremely difficult. We suggest that confirming the fusion area after hemiepiphysiodesis and determining the appropriate osteotomy site by 3D reconstruction images are important before salvage operations.

Surgical Predictors for Prevention of Postoperative Shoulder Imbalance in Lenke Type 2A Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Multicenter, retrospective cohort study. OBJECTIVE: The aim of this study was to investigate the occurrence and surgical predictors of postoperative shoulder imbalance (PSI) in Lenke type 2A adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Although several studies have investigated the factors influencing PSI in Lenke type 2 curves, no studies have analyzed PSI-related factors considering upper instrumented vertebra (UIV) and lumbar modifier type simultaneously. METHODS: Patients with Lenke Type 2A AIS treated by spinal fusion were retrospectively identified and their data were extracted from six spine centers in Japan. Inclusion criteria were age between 10 and 20 years at surgery, UIV = T2, major curve 40° to 90°, and follow-up for 24 to 30 months after surgery. We analyzed patient characteristics, surgical characteristics, and preoperative and immediate-postoperative radiographic parameters. We defined patients with lower instrumented vertebra (LIV) equal or proximal to the last touching vertebra (LTV) as selective thoracic fusion (STF-LTV) and patients with LIV distal to the LTV as non-STF-LTV. t Tests, Mann-Whitney U test, χ2 tests, Fisher exact tests, and multivariate logistic regression were used for statistical analyses. RESULTS: Among the 99 consecutive patients with a mean follow-up of 25.6 months, PSI was seen in 27 (27.3%) patients immediately after and in 17 (17.2%) patients at 24 to 30 months. The univariate analysis revealed that the significant risk factors of PSI were preoperative radiographical shoulder height, non-STF-LTV, and high main thoracic curve (MTC) correction (immediate-postoperative MTC correction rate: ≥70%), with PSI incidence of 40.0%. The multivariate logistic regression analysis indicated that interaction term of non-STF-LTV and high MTC correction was an independent risk factor for PSI (non-STF-LTV and high MTC correction, odds ratio: 5.167, 95% confidence interval: 1.470-18.159, P = 0.010). CONCLUSION: To prevent PSI in Lenke Type 2A AIS patients, surgeons should avoid the combination of non-STF-LTV and high MTC correction in those surgeries with UIV as T2.Level of Evidence: 4.

Residual lumbar curvature that developed during adolescence accelerates intervertebral disc degeneration in adulthood.

PURPOSE: To elucidate the influence of spinal deformity in adolescent idiopathic scoliosis (AIS) on lumbar intervertebral disc (IVD) degeneration in adulthood using magnetic resonance imaging (MRI). METHODS: A total of 102 patients (8 men, 94 women; mean age, 31.4 years) who had developed idiopathic scoliosis at the age of 10-18 years and underwent preoperative lumbar spine MRI at the age of ≥ 20 were included in the study. Twenty volunteers (3 men, 17 women; mean age, 33.6 years) without scoliosis were assessed as controls. We divided the adult scoliosis patients into two groups: Group A consisted of patients with lumbar modifier A, and Group BC consisted of those with modifiers B and C. IVD degeneration from L1/2 to L5/S1 was assessed by MRI. The Scoliosis Research Society-22 (SRS-22) patient questionnaire was used in the patients' clinical assessment. RESULTS: There were 40 patients in the Group A and 62 in the Group BC. Compared to the control groups, significant IVD degeneration was observed at L2/3 and L3/4 in Group A, and at all levels except for L5/S1 in Group BC. The proportion of degenerated IVDs patients (Grades 1c and 2) was significantly higher in Group BC than those in Group A at L3/L4 and L4/L5. Furthermore, the severity of IVD degeneration was significantly greater in the group BC than in the group A at all levels, except for L5/S1, especially in patients aged > 30 years. The mean scores of all subdomains in the SRS-22 questionnaire were comparable between the two groups. CONCLUSION: Our study showed that the residual lumbar curvature from AIS may have accelerated IVD degeneration in adulthood, especially in patients aged > 30 years. LEVEL OF EVIDENCE: III.

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.

Comparison of Pulmonary Function After Selective Anterior Versus Posterior Fusion for the Correction of Thoracolumbar and Lumbar Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: To compare the selective anterior spinal fusion (ASF) versus posterior spinal fusion (PSF) on postoperative pulmonary function testing (PFT) whether thoracotomy with separation of the diaphragm by anterior approach influences the PFT in thoracolumbar and lumbar adolescent idiopathic scoliosis (AIS). METHODS: A multicenter series of AIS patients who underwent selective spinal fusion were retrospectively reviewed. Seventy-nine female patients were included (mean 15.8 years). There were 35 patients in the ASF group and 44 patients in the PSF group. Patient demographics, radiographic measurements, and PFT data from preoperative to 2-year follow-up were analyzed. RESULTS: Preoperatively, there were no significant differences in PFTs between the groups. The ASF group patients were more likely to undergo shorter fusions (4.5 instrumented vertebral levels) than those in the PSF group (5.2 levels). At 2-year follow-up, forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) in ASF group were statistically lower than those in PSF group. When comparing preoperative and 2-year changes on each procedure, only %FVC showed significant difference in ASF while FVC, FEV1, and %FEV1 did not. Meanwhile, the ASF group showed a significant decrease in FVC at 6 and 12 months compared to preoperative values. In PSF group, there was a decrease at 6 months, returned to preoperative value at 1-year follow-up. CONCLUSIONS: Pulmonary function after ASF and PSF was similar at 2 years; however, anterior group did not return to the baseline at 6 months and 1 year suggesting anterior approach may affect early postoperative pulmonary function.

Intervertebral Disc Degeneration During Postoperative Follow-up More Than 10 Years After Corrective Surgery in Idiopathic Scoliosis: Comparison Between Patients With and Without Surgery.

STUDY DESIGN: A retrospective comparative study. OBJECTIVE: The aim of this study was to evaluate the difference in trends of disc degeneration (DD) at lower unfused segments (LUS) for postoperative patients who have gone through spinal instrumentation at 10-year follow-up with the natural progression of idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Studies that used magnetic resonance imaging (MRI) state that DD rates at LUS are higher than in the normal population. However, current studies do not prove that surgery is the most effective clinical method to treat idiopathic scoliosis, as no existing report compares the rates of DD with the natural history of idiopathic scoliosis. METHODS: Female patients diagnosed of scoliosis were divided into three groups: 1) surgical group: postoperative 10-year patients with severe scoliosis before operation; 2) mild scoliosis group: with comparatively equal scoliosis to postoperative patients of the same age at 10 years follow-up; 3) severe scoliosis group: without any record of corrective surgery under the assumption that the scoliosis of the surgical group have progressed according to natural history. RESULTS: MRI findings of the surgical group show DD in 32 patients (62.7%) where the highest rate of DD occurred at L5/S. In the mild scoliosis group, 21 patients (47.7%) had DD, with higher rates at L4/5 and L5/S. DD was most common in L3/4 and L4/5 in the severe scoliosis group where 27 patients (81.8%) had DD. As such, DD rates were significantly higher in the severe scoliosis group than the surgical group at the same spinal level. The same was true for the existence of low back pain, where the severe scoliosis group had greater incidence of low back pain than the surgical group. CONCLUSION: Corrective surgeries were able to reduce the incidence of DD. Radiological analysis also suggests that surgical intervention is a clinically feasible treatment for idiopathic scoliosis patients. LEVEL OF EVIDENCE: 3.

Clinical Characteristics and Thoracic factors in patients with Idiopathic and Syndromic Scoliosis Associated with Pectus Excavatum.

INTRODUCTION: The purpose of this study is to demonstrate the clinical characteristics and thoracic factors such as sternal tilt angle and Haller index in patients with idiopathic or syndromic scoliosis associated with pectus excavatum. METHODS: We performed a retrospective review on a cohort of 70 patients (37 males and 33 females) diagnosed with idiopathic and syndromic scoliosis associated with pectus excavatum between 1985 and 2014. We investigated age, location and Cobb angle of the main curve, and thoracic factors including sternal deviation and tilting angle and Haller index using radiographs and computed tomography of the chest. RESULTS: Patients' mean age at the first visit to our hospital was 10.3 years (1-18 years old). There were 41 patients with idiopathic scoliosis and 29 with syndromic scoliosis. Main curve locations were thoracic in 52 patients, thoracolumbar in 10, and lumbar in 8. The mean Cobb angle of the main curve was 45.0 degrees (11-109 degrees). The sternum was displaced on the left side in 72% of patients, central in 23%, and right in 5%. Mean sternal tilt angle was 12.4 degrees (2.3-34 degrees), and mean Haller index score was 4.9 (2.9-9.2). There was no significant correlation between Cobb angle and sternal tilt angle/Haller index. However, a significant difference was found between sternal tilt angle and Haller index. CONCLUSION: Most patients with both scoliosis and pectus excavatum have left side deviated sternum and a higher Haller index score; therefore this can negatively impact cardiac function. Prone positioning and the corrective force applied during scoliosis surgery as well as thoracic compression during cast or brace treatment may have a negative effect on cardiac function in these patients.

Proximal Junctional Kyphosis Following Posterior Hemivertebra Resection and Short Fusion in Children Younger Than 10 Years.

STUDY DESIGN: A retrospective study. OBJECTIVE: To investigate whether proximal junctional kyphosis (PJK) or obvious proximal junctional angle (PJA) changes in the sagittal plane develops following short fusion in children younger than 10 years of age with congenital scoliosis, and to investigate the possible risk factors. SUMMARY OF BACKGROUND DATA: PJK following long spinal fusion in adolescents and adults is a serious postoperative complication. Although the same problem may occur in patients with early-onset scoliosis who have undergone spine fusion, few studies have been reported any relationship between PJK and spinal fusion in young children with congenital scoliosis. MATERIALS AND METHODS: Thirty-seven children treated in a single institution between 1998 and 2010 were reviewed retrospectively. The inclusion criteria included (1) younger than 10 years of age at the time of operation; (2) simple congenital deformity; (3) hemivertebra treated by posterior hemivertebrectomy with short fusion at a maximum of 5 motion segments; and (4) minimum follow-up for 2 years. The PJA from the caudal endplate of the upper instrumented vertebra (UIV) to the cephalad endplate of the vertebra adjacent to the UIV, thoracic kyphosis (T5-T12), lumbar lordosis (T12-S1), global sagittal balance, and magnitude of scoliosis of the major curves and upper compensated curves were measured on lateral radiographs. PJK was defined by a PJA>10 degrees during the follow-up and at least 10 degrees greater than the preoperative or early postoperative measurement. Wilcoxon tests were performed for statistical analysis. RESULTS: PJK occurred in 7 of 37 patients (18.9%), during an average of 4.5±3.2 years of follow-up (2-12 y). The UIV level of children with PJK was on T9 in 4 patients, and T11, T12, and L1 in 1. Screw malposition at UIV was confirmed by postoperative computed tomography images in 6 patients. Only 1 patient with a screw deviation did not develop PJK during the follow-up period. None of the patients with PJK was symptomatic, and no patients required revision surgery because of PJK. PJK occurred and progressed during the first 6 months after surgery followed by almost no progression or slight improvement in patients that could be followed up beyond 6 months postoperatively; in association with an increase of the lumbar lordosis. CONCLUSIONS: PJK occurred in pediatric patients with simple congenital deformities following hemivertebrectomy and short fusion. PJK was more common in patients with (1) greater immediately postoperative segmental kyphosis and PJA; (2) screw malposition on the UIV; and (3) hemivertebra located on the lower thoracic or the thoracolumbar region.

Comparison of Surgical Outcomes Between Anterior Fusion and Posterior Fusion in Patients With AIS Lenke Type 1 or 2 that Underwent Selective Thoracic Fusion -Long-term Follow-up Study Longer Than 10 Postoperative Years.

STUDY DESIGN: A retrospective comparative study. OBJECTIVE: We compared the outcomes between patients treated either by selective thoracic anterior (ASF) or posterior spinal fusion (PSF), with a minimum 10-year follow-up. SUMMARY OF BACKGROUND DATA: A retrospective long-term follow-up study was conducted to compare PSF (P group) and ASF (A group) with Lenke type 1 or 2. There were no significant differences in the correction rate and incidence of degenerative discs (DDs) on the lumbar area. Loss of correction was greater in the A group. METHODS: The inclusion criteria were female, AIS Lenke type 1 or 2, minimum 10-year follow-up, MRI check-up at 5 years and 10 years postop. The number of patients, age, and curve types at the time of surgery were matched in both groups. Complications, pulmonary function, and SRS-30 were also evaluated. RESULTS: P group: adding-on (AO) occurred in 14 patients. Two patients demonstrated progression of scoliosis >5° during follow-up. Degenerative discs occurred in 43% of patients at 10 years postop. There were significant differences in the %VC and FVC before surgery and at the final visit (P < 0.05). A group: AO occurred in 16 patients. Eleven showed progression of scoliosis >5°. Degenerative disc was recognized in 53% of the patients. There was no significant difference in the pulmonary function. There was a significant difference in selfimage score in the SRS-30 between the two groups (P < 0.05). CONCLUSION: Correction of scoliosis was significantly better ASF than PSF immediately postop. Greater loss of correction occurred with ASF at postop 10 years. Although shorter segments could be fused by ASF, there was no significant difference in the incidence of DDs. Pulmonary function test results improved in the P group and were restored in the A group during the perioperative period.

The Effects of Spinal Fusion on Lumbar Disc Degeneration in Patients with Adolescent Idiopathic Scoliosis: A Minimum 10-Year Follow-Up.

STUDY DESIGN: Retrospective study. OBJECTIVES: This study focused on patients with adolescent idiopathic scoliosis (AIS) who were followed up for more than 10 years, and assessed the influence of spinal balance on lumbar degenerative changes at distal unfused segments (DUS). SUMMARY OF BACKGROUND DATA: Previous studies suggested that longer fusion segments may result in higher rates of occurrence of disc degeneration (DD) at unfused segments adjacent to the distal fused area. However, there are no existing studies that correlate the degree of DD to the location of lower instrumented vertebra (LIV) and the amount of the residual lumbar curve during the follow-up period. METHODS: Radiologic measurements were recorded at the time of surgery, immediately after surgery, and 10 years after surgery. The Pfirrmann grading scale was used to rate the MR images of these patients. The presence of vertebral DD was also used to classify patients into DD+ and DD- groups. RESULTS: 93 patients with AIS participated in this study. The average age at the time of surgery was 15.2 years; the average follow-up time was 154 months. DD was found in 45 patients (48%) and L5/S1 was the most common (40%) location in those patients. The L1 group experienced DD at a frequency of 34%, whereas the frequency increased with lower LIV placement. There was a significant difference between DD+ and DD- in age at the time of operation, the L4 tilt (pre Op. and post. 10 years), and the number of mobile segments. CONCLUSIONS: Disc degeneration occurred in 48% of the patients at the time of postop. 10 years. Disc degeneration had a tendency to occur in patients with greater preoperative and postoperative 10 years L4 tilt angle and fewer mobile segments in the lower lumbar spine. LEVEL OF EVIDENCE: Level III.

Adjacent Segment Disease After Posterior Lumbar Interbody Fusion: Based on Cases With a Minimum of 10 Years of Follow-up.

STUDY DESIGN: Retrospective case-controlled study. OBJECTIVE: To investigate the incidence of adjacent segment degeneration (ASD) and the associated risk factors during a period of at least 10 years after posterior lumbar interbody fusion (PLIF). SUMMARY OF BACKGROUND DATA: ASD is a problematic sequelae after spinal fusion surgery. Few long-term follow-up studies have investigated ASD after PLIF; thus, magnetic resonance imaging (MRI) data available for the evaluation of postoperative changes associated with ASD are limited. METHOD: One hundred one patients were retrospectively enrolled. The minimum follow-up was 10 years after surgery. Preoperative and postoperative (2, 5, and 10 yr after surgery) Radiographs and MRI images were evaluated. Disc height, vertebral slip, and intervertebral angle were examined on radiographical images. Disc degeneration and spinal stenosis on MRI images were evaluated. Risk factors for developing early-onset radiographical ASD were evaluated using a multivariate logistic regression analysis. RESULT: The degenerative changes in disc height, vertebral slip, and intervertebral angle on radiographs 10 years after surgery were found in 12, 36, and 17 cases, respectively, at the cranial-adjacent level and in 3, 6, and 11 cases, respectively, at the caudal-adjacent level. Increased disc degeneration and spinal stenosis worsening were observed in 62 and 68 cases, respectively, at the cranial-adjacent level and in 25 and 12 cases, respectively, at the caudal-adjacent level on MRI 10 years after surgery. Ten patients (9.9%) required reoperation, and 80% of revision surgeries were performed more than 5 years after the initial surgery. High pelvic incidence was a risk factor for developing early-onset radiographical ASD. CONCLUSION: The majority of the reoperations for ASD were performed more than 5 years after the initial lumbar fusion surgery, although the progression of radiographical ASD began in the early postoperative period. A high degree of pelvic incidence was a risk factor for developing early-onset radiographical ASD. Obtaining appropriate lumbar lordosis in PLIF is important for preventing ASD. LEVEL OF EVIDENCE: 4.

Scoliosis associated with airflow obstruction due to endothoracic vertebral hump.

STUDY DESIGN: A retrospective clinical study of scoliosis-associated airflow obstruction due to endothoracic vertebral hump. OBJECTIVE: The purpose of this study was to evaluate and present anatomical features of patients with scoliosis who showed airflow obstruction caused by endothoracic vertebral hump. SUMMARY OF BACKGROUND DATA: It is well known that severe scoliosis causes airflow restriction due to thoracic cage deformity. There have been few reports of clinical data and anatomical features on scoliosis associated with airflow obstruction due to endothoracic vertebral hump. METHODS: The subjects were 6 patients. The diagnoses were idiopathic scoliosis in 3 patients, symptomatic scoliosis in 2 patients, and thoracogenic scoliosis in 1 patient. The radiological outcome, comorbidities, pre- and postoperative respiratory function, and surgical complication were analyzed. RESULTS: Four patients had preoperative atelectasis on the convex side of the lower lobe and improved after the operations. All patients showed main thoracic curves and their apex was located at T7-T9. All patients had lordoscoliosis except 1, who demonstrated kyphosing scoliosis. The correction rate was 78% (62.8%-83.5%). Preoperative thoracic lordosis within the range of -5° to -47° was postoperatively corrected to a substantially normal kyphosis within the range of 9° to 24°. The average vital capacity, percent VC improved from 0.72 L (0.33-1.17 L) to 1.21 L (0.82-1.71 L) and 45.5% (37.3%- 50.8%) to 63.7% (41.0%-88.6%) relatively. Spine Penetration Index improved from 23% (18%-35%) to 16% (13%-19%). Endothoracic hump ratio improved from 1.34 (0.98-1.93) to 1.12 (0.86-1.28). CONCLUSION: Each patient with symptomatic scoliosis and thoracogenic scoliosis required relatively long periods of respiration management. Patients having lordoscoliosis with an apex located between T7 and T9 may develop airflow obstruction due to an endothoracic vertebral hump. Correction of lordoscoliosis through anterior and posterior approaches successfully improved endothoracic hump ratio and atelectasis in all patients.