Gender differences in the prevalence of low back pain associated with sports activities in children and adolescents: a six-year annual survey of a birth cohort in Niigata City, Japan.

BACKGROUND: This study was conducted to determine gender differences in the relationship between extracurricular sports activities (ECSA) and low back pain (LBP) in children and adolescents. METHODS: In a cohort analysis of a 6-year birth cohort annual survey, students were followed from the fourth to sixth grades of elementary school (E4-E6; 9-12 years old) through the first to third grades of junior high school (J1-J3; 12-15 years old). All students completed annual questionnaires on ECSA and LBP. The odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the association strength between ECSA and LBP. We also calculated the population attributable fraction (PAF), which was defined as the proportion of students with ECSA-related LBP among all students with LBP. RESULTS: ECSA was significantly associated with LBP only in grade J3 among boys (OR: 2.00, 95% CI: 1.47-2.71). On the other hand, among girls, ECSA was significantly associated with LBP in grades E5 (OR: 1.48, 95% CI: 1.00-2.20), E6 (OR: 1.91, 95% CI: 1.33-2.75), and J3 (OR: 1.81, 95% CI: 1.26-2.61). Among boys, PAF was similar in all grades (range, 10-16%), whereas among girls, the PAF varied (- 11 to 29%) and was significantly higher in girls than in boys in grades E5 (19.0% vs. 1.1%, P < 0.01) and E6 (28.8% vs. 12.8%, P < 0.01). CONCLUSIONS: Although there was a link between ECSA and LBP in both boys and girls, girls were more susceptible to ECSA-related LBP, especially in grades E5 and E6.

Natural history of the ossification of cervical posterior longitudinal ligament: a three dimensional analysis.

PURPOSE: Three-dimensional (3D) imaging using computed tomography (CT) has made it possible to accurately evaluate ossification of the posterior longitudinal ligament (OPLL). Recently, we developed a novel technique to measure ossification volume using the 3D analysis. The purpose of this study was to investigate the natural course of OPLL and the risk factors for volume progression. METHODS: Forty-one patients (22 males and 19 females) diagnosed with cervical OPLL who had been non-surgically treated were included in this study. We evaluated clinical examination, radiological findings, and the volume of ossified lesions during at least 1-year intervals. Furthermore, we performed risk factor analysis for OPLL volume progression. RESULTS: The mean ossification volume was 2047.4 ± 1437.3 mm3 in the first examination and 2201.0 ± 1524.1 mm3 in the final examination, indicating a significant increase during the follow-up period (p < 0.001). The mean annual rate of lesion increase was 4.1 ± 2.7%. Univariate regression analysis demonstrated significant relationships between the annual rate of lesion increase and age (ß = -0.48; p = 0.001), body weight (BW) (ß = 0.36; p = 0.02), and body mass index (BMI) (ß = 0.35; p = 0.03). Furthermore, age was the only significant predictor of OPLL progression (R2 = 0.23; p = 0.001) in multivariate liner regression analysis. CONCLUSIONS: Younger age, higher BW, and higher BMI are predictors of OPLL progression. Younger age is the most significant predictor in non-surgically treated patients.

Posterior instrumented fusion suppresses the progression of ossification of the posterior longitudinal ligament: a comparison of laminoplasty with and without instrumented fusion by three-dimensional analysis.

PURPOSE: There is no definitive evidence that additional instrumented fusion following laminoplasty suppresses the progression of ossification of the posterior longitudinal ligament (OPLL). Recently, we reported a novel method involving the creation of three-dimensional (3D) model from computed tomography images to measure the volume of OPLL accurately. The study aim was to evaluate whether laminoplasty with instrumented fusion suppresses the progression of OPLL in comparison with stand-alone laminoplasty by our novel 3D analysis. METHODS: The present study comprised of a group of 19 patients (14 men, five women) with OPLL treated with posterior decompression and fusion (PDF group), and a group of 22 patients (14 men, eight women) treated with laminoplasty alone (LP group). The volume of OPLL was evaluated three times during the follow-up period, and the volume change of OPLL was compared between the two groups. RESULTS: The PDF group (2.0 ± 1.7 %/year; range, -3.0 to 5.3) demonstrated lower annual rate of lesion increase compared to the LP group (7.5 ± 5.6 %/year; range, 1.0-19.2) (p < 0.001). In a notable thing, the annual rate of increase from the 2nd to the 3rd measurement significantly decreased compared with that from the 1st to the 2nd measurement in the PDF group (p < 0.05). CONCLUSION: This is the first study to prove a possible suppressant effect of additional posterior instrumented fusion on OPLL progression using novel 3D analysis.

Surgical treatment for osteoporotic thoracolumbar vertebral collapse using vertebroplasty with posterior spinal fusion: a prospective multicenter study.

PURPOSE: The study aimed to investigate the clinical outcomes and limitations after vertebroplasty with posterior spinal fusion (VP+PSF) without neural decompression for osteoporotic vertebral collapse. METHODS: We conducted a prospective multicenter study including 45 patients (12 men and 33 women, mean age: 77.0 years) evaluated between 2008 and 2012. Operation time, blood loss, visual analog scale (VAS) of back pain, neurological status, kyphosis angle in the fused area, and vertebral union of the collapsed vertebra were evaluated. RESULTS: The mean operation time was 162 min and blood loss was 381 mL. The postoperative VAS score significantly improved, and the neurological status improved in 35 patients (83 %), and none of the remaining patients demonstrated a deteriorating neurological status at two years post-operatively. The mean kyphosis angle pre-operatively, immediately post-operatively, and two years post-operatively was 23.8°, 10.7°, and 24.3°, respectively, and there was no significant difference between the angles pre-operatively and two years post-operatively. The extensive correction of kyphosis >16° was a risk factor for a higher correction loss and subsequent fracture. Union of the collapsed vertebra was observed in 43 patients (95 %) at two years post-operatively. CONCLUSIONS: The present study suggests that spinal stabilization rather than neural decompression is essential to treat OVC. Short-segment VP+PSF can achieve a high union rate of collapsed vertebra and provide a significant improvement in back pain or neurological status with less invasive surgery, but has a limit of kyphosis correction more than 16°.

Body mass index is associated with low back pain in childhood and adolescence: a birth cohort study with a 6-year follow-up in Niigata City, Japan.

PURPOSE: To investigate the successive change of low back pain (LBP) prevalence in childhood and adolescence and to examine the associations between LBP and extracurricular sports activities (ECSA) or body mass index (BMI) using a 6-year birth cohort study. METHODS: LBP reports of a grade (4,597 pupils at the beginning) were tracked over 6 years (between the ages of 9 and 14 years old), and anonymous questionnaires were distributed to them yearly. After grading the severity of the LBP into three levels and noting the transitions of the point and the lifetime prevalence of LBP, associations between point prevalence of LBP and BMI or ECSA were evaluated. RESULTS: The point prevalence of LBP had a tendency to become significantly higher as the pupils got older until they became 13 years old. The lifetime prevalence of LBP significantly increased as they got older yearly. As for the severity of LBP among students with a lifetime prevalence, the rate of more severe LBP (levels 2 and 3) increased as they got older. Significant positive associations were recognized between BMI and point prevalence of LBP in every years old (p < 0.05) and between ECSA and point prevalence of LBP at 11 (p = 0.001) and 14 years old (p < 0.001). CONCLUSIONS: The point and lifetime prevalence of LBP and the rate of more severe LBP increased as the pupils got older. BMI may be associated with LBP in childhood and adolescence.

Three-dimensional evaluation of volume change in ossification of the posterior longitudinal ligament of the cervical spine using computed tomography.

BACKGROUND: Two-dimensional imaging is not adequate for evaluating ossification of the posterior longitudinal ligament (OPLL). This study was designed to evaluate the accuracy of a novel computed tomography (CT)-based three-dimensional (3D) analysis method that we had devised to measure volume changes in OPLL. SUBJECTS AND METHODS: Twenty OPLL patients (12 male and 8 female; mean age 63.6 years) who were being followed conservatively were examined twice with an interval of at least 1 year between the two scans. The mean interval was 22 (range 12-45) months. A 3D model was created with DICOM data from CT images, using the MIMICS(®) software to calculate the volume. The mean ossification volume was determined from two measurements. Since ossification size varies widely, evaluation of change in volume is generally affected by the original size. Therefore, the change in ossification volume between the first and second CT examinations was calculated as the annual rate of progression. RESULTS: The type of OPLL was classified as continuous in 3 patients, segmented in 3, and mixed in 14. The mean ossification volume was 1,831.68 mm(3) at the first examination and 1,928.31 mm(3) at the second, showing a significant mean increase in ossification volume. The mean annual rate of lesion increase was 3.33% (range 0.08-7.79%). CONCLUSION: The 3D method used allowed detailed OPLL classification and quantification of change in the ossified volume. Thus, this method appears to be very useful for quantitative evaluation of OPLL with only minimal measurement error.

Atypical findings on magnetic resonance imaging in the patients with active pyogenic spondylitis in Japanese university hospitals.

Recently, aging population and immuno-compromised patients have been rising in Japan. Accordingly, patients with pyogenic spondylitis have been increasing and may present atypical clinical features. University hospitals treat many elderly patients and patients with poor general condition. Therefore, patients with pyogenic spondylitis treated at two university hospitals were retrospectively investigated to clarify the recent clinical and radiologic characteristics of this infection. There were 30 patients (average age: 68 years) treated in two university hospitals between 2009 and 2010. The onset was acute or subacute in 15 patients, insidious in 7 and unclassified in 8. Culture tests were performed in 25 patients, and the causative microorganisms were identified in 20 patients with the identification rate of 80%, including 4 patients infected by methicillin-resistant staphylococci. Classically, active pyogenic spondylitis is characterized by typical findings on magnetic resonance imaging (MRI): obvious signal decrease in T1-weighted image (WI) and increase in T2WI with contrast enhancement found in most of the bodies of two adjacent vertebrae and the intervening intervertebral disc. Among 29 patients with active pyogenic spondylitis, whose lesions were not in the healing stage, 16 patients demonstrated at least one of the atypical MRI findings; 9 patients showed involvement ≥ 3 vertebrae or only 1 vertebra, 5 showed the signal changes of the lesions involving small, spotty, or faint areas, and 3 showed small vertebral lesions but larger epidural or paraspinal abscesses. In conclusion, currently, about half of the patients with pyogenic spondylitis demonstrate atypical MRI findings in the university hospitals in Japan.

Polymethylmethacrylate augmentation of pedicle screws increases the initial fixation in osteoporotic spine patients.

STUDY DESIGN: A retrospective comparative study. OBJECTIVES: To investigate the clinical efficacy of polymethylmethacrylate (PMMA) augmentation in vertebral pseudarthrosis after osteoporotic vertebral fractures. SUMMARY OF BACKGROUND DATA: Despite being the most rigid form of posterior instrumentation, pedicle screws sometimes achieve poor initial fixation primarily in patients with osteoporosis. One method for improving pedicle screw fixation in osteoporotic spines is pedicle augmentation using bone cement such as PMMA. Although various biomechanical studies of osteoporotic spines have shown improved pullout strength of pedicle screws augmented with bone cement, there have been few studies that have examined the clinical significance of PMMA augmentation. METHODS: Thirty-eight patients with posterior fusion using pedicle screws for vertebral pseudarthrosis after osteoporotic vertebral fracture were included in the study. The level of fracture ranged from T7 to L5. The mean follow-up period was 31 months. Patients were divided into 2 groups: those with posterior instrumentation using pedicle screws augmented with PMMA (group C, N=17) and those without PMMA augmentation (group NC, N=21). Clinical and radiographic results for the 2 groups were compared. RESULTS: With the exception of osteoporotic status, there were no significant differences in the baseline data of the 2 groups. The incidence of clear zones around the pedicle screws was significantly suppressed in group C compared with group NC (29.4% vs. 71.4%). Correction loss was significantly decreased (3 degrees vs. 7.2 degrees) and fusion rate was significantly higher in group C (94.1% vs. 76.1%). Back pain improved in 64.7% of the group C patients. There were no perioperative complications related to the PMMA cement in group C. CONCLUSIONS: Reinforcement of pedicle screws using PMMA augmentation may be a feasible surgical technique for osteoporotic spines.

Perioperative complications of anterior cervical decompression with fusion in patients with ossification of the posterior longitudinal ligament: a retrospective, multi-institutional study.

BACKGROUND: Anterior decompression with fusion (ADF) for patients with cervical ossification of the posterior longitudinal ligament (OPLL) is reportedly associated with a higher incidence of complications than is laminoplasty. However, the frequency of perioperative complications associated with ADF for cervical OPLL has not been fully established. The purpose of this study was to investigate the incidence of perioperative complications, especially neurological complications, following ADF performed to relieve compressive cervical myelopathy due to cervical OPLL. METHODS: Study participants comprised 150 patients who had undergone ADF for cervical OPLL at 27 institutions between 2005 and 2008. Perioperative--especially neurological--complications occurring within 2 weeks after ADF were analyzed. Preoperative imaging findings, including Cobb angle, between C2 and C7 and occupying ratio of OPLL were investigated. Multivariate analysis with logistic regression was performed to identify independent risk factors for neurological complications. RESULT: Three patients (2.0 %) showed deterioration of lower-extremity function after ADF. One of the three patients had not regained their preoperative level of function 6 months after surgery. Upper-extremity paresis occurred in 20 patients (13.3 %), five of whom had not returned to preoperative levels 6 months after surgery. Patients with upper-extremity paresis showed significantly higher occupying ratios of OPLL, greater blood loss, longer operation times, fusion of more segments, and higher rates of cerebrospinal fluid leakage than those without paresis. Independent risk factors for upper-extremity paresis were a high occupying ratio of OPLL and large blood loss during surgery. CONCLUSIONS: The incidences of deterioration in upper- and lower-extremity functions were 13.3 % and 2.0 %, respectively. Patients with a high occupying ratio of OPLL are at higher risk of developing neurological deterioration.

Low back pain in childhood and adolescence: assessment of sports activities.

A cross-sectional study that targeted a total of 43,630 pupils in Niigata City, Japan was performed. The objective of the study was to evaluate the association between sports activities and low back pain (LBP) in childhood and adolescence in Japan. Regarding risk factors of LBP, a large number of studies have been conducted that have examined gender differences, height and weight, body mass index, sports time, differences in lifestyle, family history, and mental factors; however, no definitive conclusion has yet been made. A questionnaire survey was conducted using 43,630 pupils, including all elementary school pupils from the fourth to sixth grade (21,893 pupils) and all junior high pupils from the first to third year (21,737 pupils) in Niigata City (population of 785,067). 26,766 pupils who were determined to have valid responses (valid response rate 61.3%) were analyzed. Among the 26,766 pupils with valid responses, 2,591 (9.7%) had LBP at the time of the survey, and 8,588 (32.1%) had a history of LBP. The pupils were divided between those who did not participate in sports activities except the physical education in school (No sports group: 5,486, 20.5%) and those who participated in sports activities (Sports group: 21,280, 79.5%), and the difference in lifetime prevalence between No sports group and Sports group was examined. The odds ratio for LBP according to sports activity was calculated by multiple logistic regression analysis adjusted for gender, age, and body mass index. In addition, the severity of LBP was divided into three levels (Level 1: no limitation in any activity, Level 2: necessary to refrain from participating in sports and physical activities, and Level 3: necessary to be absent from school), and Levels 2 and 3 were defined as severe LBP; the severity was compared between No sports group and Sports group and in each sport's items. Moreover, in Sports group, the amount of time spent participating in sports activities were divided into three groups (Group 1: less than 6 h per week, Group 2: 6-12 h per week, and Group 3: 12.1 h per week or more), and the dose-response between the amount of time spent participating in sports activities and the occurrence of LBP were compared. In No sports group, 21.3% experienced a history of LBP; in Sports group, 34.9% experienced LBP (P < 0.001). In comparison to No sports group, the odds ratio was significantly higher for Sports group (1.57), and also significantly higher for most of the sports items. The severity of LBP was significantly higher in Sports group (20.1 vs. 3.2%, P < 0.001). The amount of time spent participating in sports activities averaged 9.8 h per week, and a history of LBP significantly increased in the group which spent a longer time participating in sports activities (odds ratio 1.43 in Group 3). These findings suggest that sports activity is possible risk factors for the occurrence of LBP, and it might increase the risk for LBP in childhood and adolescence.

Back pain in adolescents with idiopathic scoliosis: epidemiological study for 43,630 pupils in Niigata City, Japan.

There have been a few studies regarding detail of back pain in adolescents with idiopathic scoliosis (IS) as prevalence, location, and severity. The condition of back pain in adolescents with IS was clarified based on a cross-sectional study using a questionnaire survey, targeting a total of 43,630 pupils, including all elementary school pupils from the fourth to sixth grade (21,893 pupils) and all junior high pupils from the first to third year (21,737 pupils) in Niigata City (population of 785,067), Japan. 32,134 pupils were determined to have valid responses (valid response rate: 73.7%). In Niigata City, pupils from the fourth grade of elementary school to the third year of junior high school are screened for scoliosis every year. This screening system involves a three-step survey, and the third step of the survey is an imaging and medical examination at the Niigata University Hospital. In this study, the pupils who answered in the questionnaire that they had been advised to visit Niigata University Hospital after the school screening were defined as Scoliosis group (51 pupils; 0.159%) and the others were defined as No scoliosis group (32,083 pupils). The point and lifetime prevalence of back pain, the duration, the recurrence, the severity and the location of back pain were compared between these groups. The severity of back pain was divided into three levels (level 1 no limitation in any activity; level 2 necessary to refrain from participating in sports and physical activities, and level 3 necessary to be absent from school). The point prevalence was 11.4% in No scoliosis group, and 27.5% in Scoliosis group. The lifetime prevalence was 32.9% in No scoliosis group, and 58.8% in Scoliosis group. According to the gender- and school-grade-adjusted odds ratios (OR), Scoliosis group showed a more than twofold elevated odds of back pain compared to No scoliosis group irrespective of the point or lifetime prevalence of back pain (OR, 2.29; P = 0.009 and OR, 2.10; P = 0.012, respectively). Scoliosis group experienced significantly more severe pain, and of a significantly longer duration with more frequent recurrences in comparison to No scoliosis group. Scoliosis group showed significantly more back pain in the upper and middle right back in comparison to No scoliosis group. These findings suggest that there is a relationship between pain around the right scapula in Scoliosis group and the right rib hump that is common in IS.

Effect of Early vs Delayed Surgical Treatment on Motor Recovery in Incomplete Cervical Spinal Cord Injury With Preexisting Cervical Stenosis: A Randomized Clinical Trial.

Importance: The optimal management for acute traumatic cervical spinal cord injury (SCI) is unknown. Objective: To determine whether early surgical decompression results in better motor recovery than delayed surgical treatment in patients with acute traumatic incomplete cervical SCI associated with preexisting canal stenosis but without bone injury. Design, Setting, and Participants: This multicenter randomized clinical trial was conducted in 43 tertiary referral centers in Japan from December 2011 through November 2019. Patients aged 20 to 79 years with motor-incomplete cervical SCI with preexisting canal stenosis (American Spinal Injury Association [ASIA] Impairment Scale C; without fracture or dislocation) were included. Data were analyzed from September to November 2020. Interventions: Patients were randomized to undergo surgical treatment within 24 hours after admission or delayed surgical treatment after at least 2 weeks of conservative treatment. Main Outcomes and Measures: The primary end points were improvement in the mean ASIA motor score, total score of the spinal cord independence measure, and the proportion of patients able to walk independently at 1 year after injury. Results: Among 72 randomized patients, 70 patients (mean [SD] age, 65.1 [9.4] years; age range, 41-79 years; 5 [7%] women and 65 [93%] men) were included in the full analysis population (37 patients assigned to early surgical treatment and 33 patients assigned to delayed surgical treatment). Of these, 56 patients (80%) had data available for at least 1 primary outcome at 1 year. There was no significant difference among primary end points for the early surgical treatment group compared with the delayed surgical treatment group (mean [SD] change in ASIA motor score, 53.7 [14.7] vs 48.5 [19.1]; difference, 5.2; 95% CI, -4.2 to 14.5; P = .27; mean [SD] SCIM total score, 77.9 [22.7] vs 71.3 [27.3]; P = .34; able to walk independently, 21 of 30 patients [70.0%] vs 16 of 26 patients [61.5%]; P = .51). A mixed-design analysis of variance revealed a significant difference in the mean change in ASIA motor scores between the groups (F1,49 = 4.80; P = .03). The early surgical treatment group, compared with the delayed surgical treatment group, had greater motor scores than the delayed surgical treatment group at 2 weeks (mean [SD] score, 34.2 [18.8] vs 18.9 [20.9]), 3 months (mean [SD] score, 49.1 [15.1] vs 37.2 [20.9]), and 6 months (mean [SD] score, 51.5 [13.9] vs 41.3 [23.4]) after injury. Adverse events were common in both groups (eg, worsening of paralysis, 6 patients vs 6 patients; death, 3 patients vs 3 patients). Conclusions and Relevance: These findings suggest that among patients with cervical SCI, early surgical treatment produced similar motor regain at 1 year after injury as delayed surgical treatment but showed accelerated recovery within the first 6 months. These exploratory results suggest that early surgical treatment leads to faster neurological recovery, which requires further validation. Trial Registration: ClinicalTrials.gov Identifier: NCT01485458; umin.ac.jp/ctr Identifier: UMIN000006780.

Rib Hyperostosis as a Risk Factor for Poor Prognosis in Cervical Spine Injury Patients With Diffuse Idiopathic Skeletal Hyperostosis.

STUDY DESIGN: Retrospective multi-center study. OBJECTIVE: To identify the morphological features of costovertebral joints and ribs in surgically managed cervical injury patients with diffuse idiopathic skeletal hyperostosis (DISH) and to examine its impact on their vital prognosis. SUMMARY OF BACKGROUND DATA: Several reports have indicated that DISH is an independent risk factor for mortality after spinal fracture. The reason for the high mortality in cervical injury patients with DISH is unclear, although some reports have suggested a possible association between pulmonary complications and mortality. METHODS: From 1999 to 2017, a total of 50 DISH patients (44 males) with cervical spine injuries who underwent spinal surgery were enrolled (average age 74 yrs). Prognosis and clinical risk factor data were collected; the morphological features of the patients' costovertebral joints and ribs were evaluated with computed tomography. The influence of each proposed risk factor and thoracic morphological feature on mortality was tested with univariate and multivariate analyses. RESULTS: The survival rate at 5 years after surgery was 52.3%. Nineteen (38%) patients died, and the most common cause of death was pneumonia (68%). Costovertebral bone excrescences and rib hyperostosis were found to be thoracic pathognomonic signs; their frequencies were 94% and 82%, respectively, and these conditions occurred in an average of 7.0 joints and 4.7 bones, respectively. The results of the log-rank test showed a significant difference in age, injury severity score (ISS), costovertebral bone excrescences, and rib hyperostosis. The results of age-adjusted multivariate analysis indicated that age (hazard ratio [HR] = 8.65, 95% confidence interval [CI] = 1.10-68.28, P = 0.041) and rib hyperostosis (HR = 3.82, 95% CI = 1.38-10.57, P = 0.010) were associated with mortality. CONCLUSION: Reduced chest wall mobility associated with rib hyperostosis in cervical spine injury patients with DISH leads to a poor prognosis. LEVEL OF EVIDENCE: 3.

En Bloc Spondylectomy for Spinal Metastases: Detailed Oncological Outcomes at a Minimum of 2 Years after Surgery.

STUDY DESIGN: Retrospective case series. PURPOSE: To investigate the oncological outcomes, including distant relapse, after en bloc spondylectomy (EBS) for spinal metastases in patients with a minimum of 2-year follow-up. OVERVIEW OF LITERATURE: Although EBS has been reported to be locally curative and extend survival in select patients with spinal metastases, detailed reports regarding the control of distant relapse after EBS are lacking. METHODS: We conducted a retrospective review of 18 consecutive patients (median age at EBS, 62 years; range, 40-77 years) who underwent EBS for spinal metastases between 1991 and 2015. The primary cancer sites included the kidney (n=7), thyroid (n=4), liver (n=3), and other locations (n=4). Survival rates were estimated using the Kaplan-Meier method, and groups were compared using the log-rank method. RESULTS: The median operative time and intraoperative blood loss were 767.5 minutes and 2,375 g, respectively. Twelve patients (66.7%) experienced perioperative complications. Five patients (27.8%) experienced local recurrence of the tumor at a median of 12.5 months after EBS, four of which had a positive resection margin status. Thirteen patients (72.2%) experienced distant relapse at a median of 21 months after EBS. The estimated median survival period after distant relapse was 20 months (95% confidence interval, 0.71-39.29 months). No association was found between resection margin status and distant relapse. Overall, the 2-year, 5-year, and 10-year survival rates after EBS were 72.2%, 48.8%, and 27.1%, respectively. Importantly, the era in which EBS was performed did not impact the oncological outcomes. CONCLUSIONS: Our results suggest that EBS by itself, even if margin-free, cannot prevent further dissemination, which occurred in >70% of patients at a median of 21 months after EBS. These results should be considered and conveyed to patients for clinical decision-making.

Low back pain in childhood and adolescence: a cross-sectional study in Niigata City.

A cross-sectional study targeted a total of 43,630 pupils in Niigata City, Japan was performed. The objective was to clarify the present incidence of low back pain (LBP) in childhood and adolescence in Japan. It has recently been recognized that LBP in childhood and adolescence is also as common a problem as that for adults and most of these studies have been conducted in Europe, however, none have so far been made in Japan. A questionnaire survey was conducted using 43,630 pupils, including all elementary school students from the fourth to sixth grade (21,893 pupils) and all junior high students from the first to third year (21,737 pupils) in Niigata City (population of 785,067) to examine the point prevalence of LBP, the lifetime prevalence, the gender differences, the age of first onset of LBP in third year of junior high school students, the duration, the presence of recurrent LBP or not, the trigger of LBP, and the influences of sports and physical activities. In addition, the severity of LBP was divided into three levels (level 1: no limitation in any activity; level 2: necessary to refrain from participating in sports and physical activities, and level 3: necessary to be absent from school) in order to examine the factors that contribute to severe LBP. The validity rate was 79.8% and the valid response rate was 98.8%. The point prevalence was 10.2% (52.3% male and 47.7% female) and the lifetime prevalence was 28.8% (48.5% male and 51.5% female). Both increased as the grade level increased and in third year of junior high school students, a point prevalence was seen in 15.2% while a lifetime prevalence was observed in 42.5%. About 90% of these students experienced first-time LBP during the first and third year of junior high school. Regarding the duration of LBP, 66.7% experienced it for less than 1 week, while 86.1% suffered from it for less than 1 month. The recurrence rate was 60.5%. Regarding the triggers of LBP, 23.7% of them reported the influence of sports and exercise such as club activities and physical education, 13.5% reported trauma, while 55.6% reported no specific triggers associated with their LBP. The severity of LBP included 81.9% at level 1, 13.9% at level 2 and 4.2% at level 3. It was revealed that LBP in childhood and adolescence is also a common complaint in Japan, and these findings are similar to previous studies conducted in Europe. LBP increased as the grade level increased and it appeared that the point and lifetime prevalence in adolescence are close to the same levels as those seen in the adulthood and there was a tendency to have more severe LBP in both cases who experienced pain for more than 1 month and those with recurrent LBP.

Significant correlation between cerebrospinal fluid nitric oxide concentrations and neurologic prognosis in incomplete cervical cord injury.

In animal models of spinal cord injury (SCI), inducible NO (nitric oxide) synthase is expressed in the spinal cord immediately after sustaining SCI. Excessive NO production has cytotoxic effects and induces neuronal apoptosis, causing neural degeneration and neurodysfunction in the spinal cord. Little is known, however, about the relationship between NO(x) (NO metabolites: nitrite and nitrate) levels in the cerebrospinal fluid (CSF) and neurologic severity or recovery in clinical cases. The objective of the present study was to examine the correlation between CSF NO(x) levels and neurologic severity or recovery in SCI. Twenty-five patients with incomplete cervical cord injury (CCI) were examined. Eight cases were treated conservatively (non-operated group). Seventeen cases underwent surgical intervention (operated group). NO(x) levels in the CSF were measured using the Griess method. The severity of the neurologic impairment was assessed using Frankel's classification and the American Spinal Injury Association motor score (ASIA MS). The degree of neurologic recovery was assessed using Frankel's classification and the ASIA motor recovery percentage (MRP). There was no significant difference in the NO(x) levels between the CCI group (NO(x) levels: 5.9 +/- 0.7 microM) and the 36 control subjects (1 volunteer and 35 patients without neurologic disorders, NO(x) levels: 4.9 +/- 0.3 microM). There was no significant difference in NO(x) levels and MRP between the non-operated group and the operated group. The NO(x) levels in total SCI group were significantly correlated with the ASIA MS and MRP. There was a significant correlation between CSF NO(x) levels and neurologic severity or recovery in incomplete CCI.

Radiographic Outcomes of Upper Cervical Fusion for Pediatric Patients Younger Than 10 Years.

PURPOSE: This study aimed to investigate radiographic outcomes after posterior spinal fusion (PSF) for pediatric patients younger than 10 years with upper cervical disorders. METHODS: Thirteen patients (mean age at surgery, 5.9 years; range, 1 to 9 years) who underwent PSF with a minimum of 2 years of follow-up (mean, 5.8 years) were included. Diagnoses were atlanto-axial instability due to congenital disorders for 11 patients and atlanto-axial rotatory fixation for 2 patients. The fusion area was occipito-cervical for 7 patients and C1/2 for 6 patients. PSF was performed using rigid screw-rod constructs for 6 patients and conventional techniques for 7 patients. Ten patients required halo immobilization after surgery. Fusion status, perioperative complications, radiographic alignment, and range of motion (ROM) from C2 to C7 were evaluated. RESULTS: Twelve patients successfully achieved bony fusion (fusion rate, 92%), but complications occurred in 5 patients. Regarding radiographic measures (preoperative/postoperative/final follow-up), the mean atlanto-dental interval was significantly reduced (8.0 mm/2.7 mm/3.5 mm) and the C2-7 ROM was increased (from 49.4 degrees to 66.0 degrees) at the final follow-up (both comparisons, p<0.05). Sagittal alignment was unchanged. CONCLUSION: Use of rigid screw-rod instrumentation in the upper cervical spine with careful radiological evaluation is amenable for pediatric patients younger than 10 years. However, conventional procedures such as wiring fixation with rigid external immobilization are still alternative options for preventing serious neurological and vascular complications.

Surgical Outcomes of Posterior Spinal Fusion Alone Using Cervical Pedicle Screw Constructs for Cervical Disorders Associated With Athetoid Cerebral Palsy.

STUDY DESIGN: Retrospective case series. OBJECTIVE: The aim of this study was to investigate clinical outcomes after posterior spinal fusion (PSF) using cervical pedicle screw (CPS) constructs for cervical disorders associated with athetoid cerebral palsy (CP). SUMMARY OF BACKGROUND DATA: Traditionally, most patients with cervical myelopathy associated with CP have required combined anterior and posterior fusion to achieve solid stability against severe involuntary movement. METHODS: Thirty-one CP patients with cervical disorders who underwent PSF alone with a minimum 2-year follow-up (mean 58 months) were analyzed. All patients were treated with PSF using CPS constructs with or without decompression procedures. The average number of fused segments was 5.1 (range, 1-10 segments), and a halo jacket was applied in 16 patients for at least 2 months after surgery. Clinical outcomes using the Japanese Orthoedic Association scoring system (JOA score) and walking ability, radiographic sagittal alignment, fusion status, and surgery-related complications were evaluated. RESULTS: The JOA score improved from 8.3 points preoperatively to 10.9 points at the final follow-up (P < 0.05). Although no patients experienced deterioration in their walking ability postoperatively, 10 patients were unable to walk at the final follow-up. Sagittal alignment, including C0-2 angle, C2-7 angle, and local alignment in fused segments, was maintained postoperatively. Twenty-five patients achieved fusion at the final follow-up (fusion rate: 81%), and fivepatients with nonunion required additional surgery. With regard to complications, 5 patients encountered postoperative upper extremity palsy. CONCLUSION: The CPS construct is amenable to achieve a relatively high fusion rate without correction loss, and good clinical outcomes can be achieved with a posterior single approach for CP patients. In the future, efforts should be made to make appropriate decisions regarding the fusion area, take preventative measures against postoperative upper extremity palsy, and simplify external orthoses after surgery, especially with the use of a halo jacket. LEVEL OF EVIDENCE: 4.

Nitric oxide in cerebrospinal fluid and local inducible nitric oxide synthase after cauda equina compression in rats.

We investigated the time course of changes in nitric oxide metabolite (NO2- plus NO3-: NOx) levels in the cerebrospinal fluid and the expression of local inducible nitric oxide synthase following cauda equina compression in rats. Cerebrospinal fluid NOx levels were significantly increased from 12 h to 3 days after compression, and decreased thereafter. Histologically, inducible nitric oxide synthase immunoreactivity was observed in macrophages that infiltrated the dura mater on days 1 and 3 after compression, but not in foamy macrophages in the parenchyma of the cauda equina observed afterwards. The pattern of NOx levels coincided with the appearance of inducible nitric oxide synthase labeled macrophages, indicating a critical role of these cells as the main synthesizers of NOx in the acute stage of cauda equina compression.

Critical Values of Facet Joint Angulation and Tropism in the Development of Lumbar Degenerative Spondylolisthesis: An International, Large-Scale Multicenter Study by the AOSpine Asia Pacific Research Collaboration Consortium.

STUDY DESIGN: An international, multicenter cross-sectional image-based study performed in 33 institutions in the Asia Pacific region. OBJECTIVE: The study addressed the role of facet joint angulation and tropism in relation to L4-L5 degenerative spondylolisthesis (DS). METHODS: The study included 349 patients (63% females; mean age: 61.8 years) with single-level DS; 82 had no L4-L5 DS (group A) and 267 had L4-L5 DS (group B). Axial computed tomography and magnetic resonance imaging were utilized to assess facet joint angulations and tropism (i.e., asymmetry between facet joint angulations) between groups. RESULTS: There was a statistically significant difference between group A (left mean: 46.1 degrees; right mean: 48.2 degrees) and group B (left mean: 55.4 degrees; right mean: 57.5 degrees) in relation to bilateral L4-L5 facet joint angulations (p < 0.001). The mean bilateral angulation difference was 7.4 and 9.6 degrees in groups A and B, respectively (p = 0.025). A critical value of 58 degrees or greater significantly increased the likelihood of DS if unilateral (adjusted OR: 2.5; 95% CI: 1.2 to 5.5; p = 0.021) or bilateral facets (adjusted OR: 5.9; 95% CI: 2.7 to 13.2; p < 0.001) were involved. Facet joint tropism was found to be relevant between 16 and 24 degrees angulation difference (adjusted OR: 5.6; 95% CI: 1.2 to 26.1; p = 0.027). CONCLUSIONS: In one of the largest studies assessing facet joint orientation in patients with DS, greater sagittal facet joint angulation was associated with L4-L5 DS, with a critical value of 58 degrees or greater increasing the likelihood of the condition for unilateral and bilateral facet joint involvement. Specific facet joint tropism categories were noted to be associated with DS.