Does global spinal alignment affect the use of walking aids after multi-segment spinal fixation for patients with ASD? A multicenter retrospective study.

PURPOSE: This study aimed to clarify the relation between global spinal alignment and the necessity of walking aid use in patients with adult spinal deformity (ASD) and to investigate the impact of spinal fixation on mobility status after surgery. METHODS: In total, 456 older patients with ASD who had multi-segment spinal fixation surgery and were registered in a multi-center database were investigated. Patients under 60 years of age and those unable to walk preoperatively were excluded. Patients were classified by their mobility status into the independent, cane, and walker groups. Comparison analysis was conducted using radiographic spinopelvic parameters and the previously reported global spine balance (GSB) classification. In addition, preoperative and 2 years postoperative mobility statuses were investigated. RESULTS: Of 261 patients analyzed, 66 used walking aids (canes, 46; walkers, 20). Analysis of preoperative radiographical parameters showed increased pelvic incidence and pelvic incidence-lumbar lordosis mismatch in the walker group and increased sagittal vertebral axis in the cane and walker groups versus the independent group. Analysis of GSB classification showed a higher percentage of walker use in those with severe imbalance (grade 3) in the sagittal classification but not in the coronal classification. While postoperative radiographical improvements were noted, there was no significant difference in the use of walking aids before and 2 years after surgery (P = 0.085). CONCLUSION: A significant correlation was found between "sagittal" spinal imbalance and increased reliance on walking aids, particularly walkers. However, the limitation of improvement in postoperative mobility status suggested that multiple factors influence the mobility ability of elderly patients with ASD.

Risk Factors for Neuropathic Pain in Middle-Aged and Elderly People: A Five-Year Longitudinal Cohort in the Yakumo Study.

OBJECTIVE: To determine the risk factors for new neuropathic pain (NeP) after five years in healthy middle-aged and elderly volunteers. DESIGN: Prospective longitudinal cohort study (Yakumo study). SETTING: Clinical evaluation in a health checkup. SUBJECTS: A total of 366 people (male N = 146, female N = 220, average age = 63.5 years) who did not have NeP in 2013 were examined. METHODS: NeP was diagnosed based on a painDETECT questionnaire score ≥13. Body mass index (BMI), comorbidity, low back pain (LBP), sciatica, physical ability, grip and back muscle strength, osteoporosis, sarcopenia, frailty, spinal alignment, and quality of life (QOL) with the SF36 in 2013 were compared between NeP(+) and NeP(-) subjects in 2018 using multivariate logistic regression analysis. RESULTS: The NeP(+) rate in 2018 was 5.2%, with no significant differences in age and gender. NeP(+) subjects had significantly lower BMI, severe sciatica, poor gait ability, higher rates of osteoporosis and sarcopenia, greater lumbar kyphosis and spinal inclination, and poorer mental health in 2013. Poor gait ability (odds ratio [OR] = 8.05), low BMI (OR = 2.31), lumbar kyphosis (OR = 1.38), low percentage of the young adult mean (OR = 1.15), and low mental QOL (OR = 1.06) were identified as significant and independent risk factors for new NeP after five years. CONCLUSIONS: This longitudinal cohort study identified five independent risk factors for development of new NeP after five years, with related factors of spinal inclination, sarcopenia, and sciatica. New NeP may be prevented by intervention or treatment of these factors at an early stage in relatively healthy middle-aged and elderly people.

A comparative study of two reconstruction procedures for osteoporotic vertebral fracture with lumbar spinal stenosis: Posterior lumbar interbody fusion versus posterior and anterior and combined surgery.

BACKGROUND: Optimal treatment of lumbar spinal stenosis (LSS) with neurological deficit due to osteoporotic vertebral fractures (OVFs) has been controversial. We assessed the usefulness, safety, and efficacy of posterior lumbar interbody fusion (PLIF) for LSS with neurological deficit due to OVFs and compared this procedure to posterior/anterior combined surgery (PACS). METHODS: Of 36 consecutive patients with LSS with neurological deficit due to OVFs, 15 underwent PLIF (6 males, 9 females; mean age, 74 years), and 21 underwent PACS (4 males, 17 females; mean age, 70 years). Surgical complications, clinical outcomes (operative time, blood loss, American Spinal Injury Association Impairment Scale [AIS], activities of daily living [ADLs]), and sagittal alignment were investigated. Bony fusion was assessed using plain and functional X-rays and computed tomography scans. RESULTS: There were no significant differences in age, sex, or disease or follow-up duration between the groups. Operative time was significantly shorter and intraoperative blood loss significantly less in the PLIF than in the PACS groups. AIS and ADL improved significantly postoperatively in both groups. No significant difference was observed in neurological improvement, correction angle, loss of correction, and surgical complications. No pseudarthrosis occurred, and no patient required additional surgery in the PLIF group. CONCLUSIONS: PLIF for LSS with neurological deficit due to OVFs achieves posterior rigid fixation with instrumentation, anterior column reconstruction by interbody fusion, and adequate decompression using a single posterior approach. This less invasive procedure is a useful reconstructive surgery option.

Impact of comorbidity rates of lumbar spondylosis, knee osteoarthritis, and osteoporosis on physical QOL and risk factors for poor physical QOL in middle-aged and elderly people.

Purpose: To examine effects of combined osteoporosis (P), knee osteoarthritis (K-OA), and lumbar spondylosis (L-OA) on quality of life (QOL), and identify risk factors for poor QOL.Methods: 1021 subjects (440 males, 581 females, mean age: 63.4 years) were prospectively included. Osteoporosis (%YAM ≤70%), K-OA (Kellgren-Lawrence grade ≥2), and L-OA (Nathan class ≥3) were defined. Subjects were divided into groups 0 to 3 based on the number of comorbid diseases, and into groups P, K, and L (one disease), PK, PL, and KL (two diseases), and PKL (three diseases). Clinical variables and QOL were compared, and risk factor analysis was conducted.Results: BMI, muscle strength, pain, and spinal inclination significantly increased and physical QOL worsened with more comorbidities. Though age did not differ among disease groups, BMI was significantly higher in groups K and L than in group P. Groups including subjects with L-OA had significantly lower lumbar lordosis and larger spinal inclination. In multivariate logistic regression analysis adjusted for age and gender, group KL, spinal inclination, gait speed, grip strength, and pain were risk factors for poor physical QOL.Conclusion: Increased comorbidity has a negative impact on physical QOL, and six risk factors for poor physical QOL were identified.

Weakness of grip strength reflects future locomotive syndrome and progression of locomotive risk stage: A 10-year longitudinal cohort study.

Objectives: Grip strength is a simple indicator of physical function. The goal of this retrospective study was to examine whether grip strength reflects locomotive syndrome and locomotive risk stage 10 years later.Methods: The participants were 88 Japanese adults aged >40 years who attended a health check-up in 2006. Relationships of baseline grip strength with physical performance and locomotive risk stage after 10 years were assessed in males and females.Results: The 88 subjects (31 males, 57 females; average age 61.6 in 2006) were followed for 10 years. Grip strength in 2006 had significant positive correlations with grip strength and back muscle strength, and negative correlations with 10 m-gait time and 3m Timed Up and Go (3m-TUG) test after 10 years (p < .05). Subjects with higher and lower grip strength in 2006 did not differ significantly in age, but had significant differences in physical performance, GLFS-25 (25-question Geriatric Locomotive Function Scale) scores and locomotive risk stage after 10 years (p < .05). Same result was also obtained in the examination by gender.Conclusion: Weak grip strength was significantly related to future physical status, and these findings were unaffected by age. Weak grip strength could be a risk factor for future locomotive syndrome and locomotive risk in community-dwelling people.

Declining neck circumference is an anthropometric marker related to frailty in middle-aged and elderly women.

Objectives: Neck circumference (NC) has been associated with cardiovascular disease and metabolic syndrome. However, the association between NC and frailty remains unknown. We aimed to determine the relationship between frailty and NC in middle-aged and elderly women.Methods: Frailty was diagnosed based on the Japanese version of the Cardiovascular Health Study criteria. Of women who underwent health checkup, 295 women with the following measurements were targeted: four trunk circumferences and appendicular skeletal muscle index (aSMI) measured using bioelectrical impedance analysis; albumin, total cholesterol, triglycerides, and C-reactive protein levels measured using a blood test; and physical function measured using back muscle strength and timed up-and-go test (TUG). Normal and frailty group comparisons were conducted using a statistical method.Results: Significant differences were observed between the two groups in terms of age, body mass index, all trunk circumferences, aSMI, back muscle strength, and TUG. Logistic regression analysis showed that NC was more related with frailty among the four trunk circumferences. In multiple regression analysis, declining NC was significantly associated with frailty.Conclusion: In middle-aged and elderly women, NC has a significant association with frailty. Declining NC was shown to be an anthropometric marker of frailty, and may be a frailty risk factor.

Shoulder pain has most impact on poor quality of life among various types of musculoskeletal pain in middle-aged and elderly people: Yakumo study.

Objectives: To investigate the severity and effect on quality of life (QOL) of various types of pain in healthy volunteers.Methods: A total of 384 subjects (male: 158, female: 226, average age: 63 years) were included in a prospective cohort study (Yakumo study). Shoulder pain, low back pain (LBP), sciatica, knee pain, and the American Shoulder and Elbow Surgeons (ASES) shoulder score were evaluated with SF-36.Results: The prevalence of shoulder pain, LBP, sciatica, and knee pain was 42%, 44%, 16%, and 48%, respectively, with similar severities of pain. Shoulder pain visual analogue scale (VAS) and ASES shoulder scores were significantly correlated with SF-36 domains. Subjects with poor physical QOL had significantly higher VAS scores for all pain types and a lower ASES shoulder score. Shoulder pain VAS was also significantly related to poor mental QOL. Multivariate regression analysis adjusted for age and gender showed that shoulder pain VAS (OR: 1.25, p < .05) and 10-m gait speed (OR: 1.82, p < .05) were significant independent risk factors for poor physical QOL.Conclusion: Only shoulder pain of similar severity to other pain and shoulder complaints impacted on both physical and mental QOL. The severity of shoulder pain was an independent risk factor for poor physical QOL.

Epidemiology and effect on physical function of osteosarcopenia in community-dwelling elderly people in Japan.

Objective: To determine the prevalence of osteosarcopenia and its relationship with physical function in elderly people in Japan.Methods: The subjects were 427 healthy volunteers over 65 years old (205 males, 222 females, average age 71.4 years) who attended health checkups in 2016 and 2017. Body mass index (BMI), bone mineral density in the calcaneus (%YAM), physical parameters, and skeletal muscle mass were measured. The appendicular skeletal muscle index (aSMI) was calculated as arm and leg skeletal muscle mass/height2. Osteoporosis was defined as %YAM < 70%, sarcopenia as aSMI < 7.0 kg/m2 (males) and <5.8 kg/m2 (females), and osteosarcopenia as the presence of sarcopenia and osteoporosis.Results: Osteoporosis alone was diagnosed in 60 subjects (14%), sarcopenia alone in 55 (13%), and osteosarcopenia in 36 (8%). The prevalence of osteosarcopenia was 8% in all subjects, 12% in females, and 4% in males. BMI and back muscle strength were significantly lower in osteosarcopenia than in sarcopenia alone (p < .05); and weight, BMI, body fat, grip strength, and back muscle strength were significantly lower in osteosarcopenia than in osteoporosis alone (p < .05).Conclusion: Osteosarcopenia was significantly associated with muscle weakness. Further studies to identify other related factors are needed for prevention and treatment of osteosarcopenia.

Reduction in body cell mass as a predictor of osteoporosis: A cross-sectional study.

Objectives: Improvement of nutritional status, which may help prevent osteoporosis, can be assessed using the body cell mass (BCM) index, measured by the bioelectrical impedance analysis (BIA). However, the relationship between BCM and osteoporosis is not clear. This cross-sectional study investigated the association between osteoporosis and four components of body composition, including BCM.Methods: The study included 600 participants who underwent measurements of bone status by quantitative ultrasound and body composition by BIA at an annual health check-up. Normal and osteoporosis groups were compared.Results: There were 414 and 186 participants in the normal and osteoporosis groups, respectively. Significant differences between the two groups were observed in age, sex, height, weight, BCM, extracellular water (ECW) content, and minerals, even after adjusting for age and sex. In logistic regression analysis, BCM, age, and ECW were significant risk factors for osteoporosis. Furthermore, BCM and ECW in males and BCM and age in females were significant risk factors for osteoporosis.Conclusion: Of the four body composition components measured with BIA, reduction in BCM most reflected osteoporosis. BCM was a significant risk factor in both sexes for osteoporosis. BCM can be easily measured, and may be useful in the prevention and treatment of osteoporosis.

Characteristics of multi-channel Br(E)-MsEP waveforms for the lower extremity muscles in thoracic spine surgery: comparison based on preoperative motor status.

PURPOSE: To evaluate the characteristics of brain-evoked muscle action potential [Br(E)-MsEP] waveforms of lower limb muscles in thoracic spine surgery. METHODS: The subjects were 159 patients who underwent thoracic spine surgery with intraoperative Br(E)-MsEP monitoring from January 2009 to December 2015, using a total of 2226 muscles in the extremities. The waveform derivation rate for each lower extremity muscle was examined at baseline and intraoperatively. Data were interpreted based on the preoperative motor status. RESULTS: The preoperative ambulatory and non-ambulatory rates were 38% (60/159, McCormick grades I and II) and 62% (99/159, grades III-V), respectively. Eleven cases (all non-ambulatory) had undetectable baseline waveforms in all muscles, and in 19 cases (12%) a baseline waveform could only be derived from the abductor hallucis (AH). The waveform derivation rate in all lower limb muscles was significantly higher in ambulatory cases (p < 0.05), and the rates for the AH were the highest in both groups (p < 0.05). Postoperative paralysis occurred in 31 cases (19%). A decrease in intraoperative amplitude of ≥ 70% from baseline occurred in 54 cases and had sensitivity of 100% and specificity of 82% for prediction of postoperative motor deficit. CONCLUSIONS: This is the first study of Br(E)-MsEP waveforms for each lower limb muscle based on preoperative ambulatory status. Detection of waveforms from distal muscles was still possible in a case with preoperative motor deficit, and the AH had an especially high derivation rate, even in cases with preoperative muscle weakness. Collectively, the results support use of Br(E)-MsEP monitoring using the AH in the lower extremities.

Variety of preoperative MRI changes in spinal cord ependymoma of WHO grade II: a case series.

PURPOSE: To report a case series of surgically proven spinal ependymomas of WHO grade II in which there were changes in the preoperative MRI characteristics over time. METHODS: A total of 71 patients with spinal cord ependymoma of WHO grade II underwent surgery. There were ten cases in which surgery was performed at an average of 2.2 years after the tumor was found. Cystic components, syringomyelia, hemorrhage "cap sign," Gd enhancement pattern, characteristic changes in MRI, MIB-1 index, and neurological assessment during the preoperative period were examined. RESULTS: Cases with a huge cyst showed further enlargement of the cyst on the caudal and rostral sides with hemosiderin formation over time and changes in the pattern of Gd enhancement. In contrast, cases without initial cyst did not show cyst formation, and nodular homogeneous lesion remained without changes in Gd enhancement. Regarding neurological status, two cases with cyst enlargement and hemosiderin formation had worsened non-independent gait preoperatively. CONCLUSIONS: MRI in cases of spinal ependymomas of WHO grade II showed characteristics such as hemorrhage and cyst formation that varied over time. In particular, cases with cyst and hemosiderin showed tumor enlargement, including enlargement of lesions on the caudal and rostral sides and enlargement of Gd-enhanced lesions. These characteristics might influence gait ability during preoperative period. We emphasize that early surgery is still the standard of care for cervical intramedullary ependymoma, and our findings in this study should not be interpreted to indicate that such early surgery is not necessary in symptomatic cases. These slides can be retrieved under electronic supplementary material.

Increasing postural sway in balance test is related to locomotive syndrome risk: A cross-sectional study.

BACKGROUND: Locomotive syndrome risk level has been recently proposed to evaluate physical ability. Impaired balance control is one of the most important risk factors for falls. However, the relationship between locomotive syndrome risk and postural sway according to the balance test is unclear. This study aimed to investigate the relationship between locomotive syndrome risk and balance test results, including muscle mass and physical function, in a large-scale prospective general health checkup. METHODS: We enrolled 292 participants who underwent a basic health checkup and conducted a two-step test, stand-up test, evaluation using a 25-question geriatric locomotive function scale for the locomotive syndrome risk test, balance test, appendicular skeletal muscle mass measurement by bioelectrical impedance analysis, evaluation of physical function by the timed-up-and-go test, and back muscle and grip strength evaluation. A statistical comparative study was then conducted between normal and locomotive syndrome risk groups. Subsequently, significant factors for locomotive syndrome risk were investigated by multivariate analysis. RESULTS: The comparative study was conducted by adjusting age and sex using a generalized linear model. No significant difference in muscle mass existed, but postural sway in the balance test significantly increased in the people at locomotive syndrome risk. Among the four posturographic variables by balance test, increase in back-and-forth sway was the most remarkable variable associated with locomotive syndrome risk together with back muscle strength, body mass index, and the timed-up-and-go test by logistic regression analysis. This posturographic variable was significantly related to the timed-up-and-go test and leg skeletal muscle mass by multiple regression analysis. CONCLUSIONS: A relationship was recognized between locomotive syndrome risk and postural sway. In particular, increase in back-and-forth sway was an important factor for locomotive syndrome risk. If the balance test shows an increase in back-and-forth sway, attention should be paid to locomotive syndrome risk for possible intervention and early treatment.

The decreasing phase angles of the entire body and trunk during bioelectrical impedance analysis are related to locomotive syndrome.

BACKGROUND: The phase angle (measured via bioelectrical impedance analysis [BIA]) is an indicator of cell membrane function and used for prognostic evaluation of diseases. Locomotive syndrome (LS) has been advocated in the evaluation of physical ability. This study aimed to determine the relationship between LS and the phase angle as well as muscle mass, muscular strength, and motor function. METHODS: In this prospective cohort study, 541 patients undergoing a health checkup participated. All participants were assessed using a 25-question geriatric locomotive function scale for the diagnosis of LS, phase angle, and muscle mass measurements via BIA. Grip strength, back muscle strength, and 3-m timed-up-and-go (TUG) test measurements were used as physical performance tests. Patients were divided into non-LS and LS groups, and their characteristics were compared. We assessed whether the phase angle was related to LS, whether it could be a risk factor in multivariate analysis, and the most important part of the phase angle. RESULTS: Age, the whole body phase angle, grip strength, back muscle strength, and TUG test result were significantly different between the two groups. Logistic regression analysis revealed that the whole body phase angle and TUG test result were risk factors of LS. Based on the subanalysis targeting specific phase angles, the trunk phase angle was a significant important factor for LS. CONCLUSION: The phase angle was significantly related to LS, and the decreased phase angle was a significant risk factor of LS together with the TUG test result. Furthermore, in subgroup analysis, the phase angle of the trunk was a significant important factor of LS. BIA can be performed conveniently, and it has been widely used for health checkups and in clinical practice. Focusing on the phase angle in BIA may be additionally helpful for the early detection and early intervention of LS.

Relationship between locomotive syndrome and body composition among community-dwelling middle-age and elderly individuals in Japan: The Yakumo study.

OBJECTIVES: Locomotive syndrome (LS) is a condition requiring nursing care for musculoskeletal disorders. Our aim was to evaluate the correlation between body composition, measured by bioelectrical impedance analysis (BIA), and LS, measured using the 25-question Geriatric Locomotive Functional Scale (GLFS-25). METHODS: We enrolled 286 individuals who were undergoing regular health follow-up. All individuals completed the GLFS-25, body composition analysis by BIA, and five physical performance tests related to LS: timed up-and-go test, 10-m gait time, maximum stride length, back strength, and grip strength. Measured variables and demographic data were compared between individuals with and without LS. RESULTS: The extracellular water ratio, the extracellular water/total body water (ECW/TBW) ratio differentiated the LS and non-LS groups (p=.005), with all physical function measures being lower among individuals with a high, compared to low, ECW/TBW ratio. The risk ratio for LS among individuals with a high ECW/TBW ratio was 2.31, with an odds ratio of 2.67. CONCLUSION: The ECW/TBW ratio is predictive of LS. Based on our results, we propose that BIA should routinely be performed, with follow-up and intervention, as needed, for individuals with a high ECW/TBW ratio, as they are at risk for developing LS.

The decrease in phase angle measured by bioelectrical impedance analysis reflects the increased locomotive syndrome risk in community-dwelling people: The Yakumo study.

OBJECTIVES: The locomotive syndrome (LS) risk test has recently been advocated for the evaluation of physical ability. Phase angle measurement by bioelectrical impedance analysis (BIA) is an indicator of cellular health and muscle mass. We aimed to investigate how muscle mass and phase angle are related to LS risk stage. METHODS: A prospective cohort study was conducted in 311 patients who were undergoing a health checkup. All participants performed the two-step test, stand-up test, and 25-question geriatric locomotive function scale components of the LS risk test. Muscle mass and phase angle were measured using BIA. A comparison study was conducted among the three LS risk stages. RESULTS: In the trend test, phase angle decreased significantly as the LS risk stage progressed, whereas muscle mass did not show a significant difference. After adjusting for age and sex, phase angle showed a significant difference among all LS risk stages. Muscle mass did not show a significant difference between no risk and stage 1. CONCLUSION: Compared to muscle mass, phase angle more strongly reflects LS risk and becomes significantly reduced at later LS risk stages. Phase angle can be a useful screening tool for LS risk.

Predictors of locomotive syndrome in community-living people: A prospective five-year longitudinal study.

Objectives: Locomotive syndrome (LS) in middle-aged and elderly people has a high risk of a need for nursing care. The goal of the study was to examine predictors of LS in a prospective longitudinal study. Methods: The subjects were 205 people (87 males, 118 females) aged >40 years who underwent physical examinations and completed health questionnaires in health checkups in the Yakumo study in 2011 and 2016. LS was defined as ≥16 on the 25-Question Geriatric Locomotive Function Scale (GLFS-25). Subjects with LS in 2011 were excluded. Associations of all variables with the GLFS-25 score were analyzed using univariate and multivariate analyses. A receiver operating characteristic (ROC) curve for each physical measurement test was constructed to determine the best threshold value. Results: The subjects were divided into LS (n = 21) and non-LS (n = 184) groups, based on the 2016 checkup. In multivariate analysis, GLFS-25 (odds ratio [OR] = 1.437; p < 0.01), one-leg standing time (OR= 1.043, p < 0.05), and back muscle strength (OR =0.961, p <0.05) were significant predictors of LS. ROC analyses gave GLFS-25 scores of 6.2 and 6.8, one-leg standing times of 26.8 and 23.3 s, and back muscle strengths of 75.2 and 49.5 kg as thresholds for prediction of future LS in males and females, respectively. Conclusions: GLFS-25 score, one-leg standing time, and back muscle strength were identified as significant risk factors for LS in community-dwelling people, and threshold values were determined for these factors in a longitudinal study. For elderly people, these indicators could be predictors of locomotive syndrome, and may have validity for assessment of improvement of physical abilities through muscle training and body balance training.

Predictors of presarcopenia in community-dwelling older adults: A 5-year longitudinal study.

Objectives: Sarcopenia is an aging-induced decrease in muscle mass that increases frailty and fall in elderly people. Presarcopenia corresponds to the preliminary stage of sarcopenia. The purpose of this prospective study is to examine predictors of presarcopenia in health screening.Methods: The subjects were 124 community residents aged ≥60 years (55 males, 69 females, average age 70.2 years) who attended local government health checkups in 2010 and 2015, as part of the Yakumo study, and did not have presarcopenia in 2010. Body mass index (BMI), waist and hip circumferences, grip strength, bone mineral density (BMD), 10-m gait time, back muscle strength, and stride length were measured. Presarcopenia was defined using the appendicular skeletal muscle index (arm and leg skeletal muscle mass/height2).Results: The prevalences of presarcopenia in 2015 in males and females were 21.8% (12/55) and 30.4% (21/69), respectively. BMI, grip strength, BMD, back muscle strength, and osteoporosis deteriorated significantly more in the pre-sarcopenia group (n = 33) compared with controls (n = 91; no presarcopenia in 2015). In multivariate analysis, osteoporosis (OR 3.12, 95% CI 1.07-9.09; p < .05) was significantly associated with presarcopenia after 5 years.Conclusions: Establishment of risk factors for future pre-sarcopenia may allow development of evidence-based prevention strategies for this condition.

Wave changes in intraoperative transcranial motor-evoked potentials during posterior decompression and dekyphotic corrective fusion with instrumentation for thoracic ossification of the posterior longitudinal ligament.

BACKGROUND: A prospective clinical study of amplitudes of intraoperative transcranial motor-evoked potentials (TcMEPs) was performed in patients undergoing surgery for the posterior longitudinal ligament of thoracic spine (T-OPLL). OBJECTIVE: To investigate intraoperative TcMEPs during posterior decompression and dekyphotic corrective fusion with instrumentation for T-OPLL. METHODS: The subjects were 33 patients with an average age of 48 years at surgery who underwent posterior decompression and fusion with instrumentation under intraoperative TcMEP monitoring. Age, gender, BMI, modified McCormick scale, prone and supine position test (PST), operative time, estimated blood loss, and Japanese Orthopaedic Association (JOA) score were recorded. Rates of successful appearance of TcMEPs, factors related to successful appearance, intraoperative amplitude changes, procedures related to amplitude deterioration, recovery of amplitude, procedures related to recovery, and postoperative paralysis were also investigated. RESULTS: The rate of appearance was highest from the abductor hallucis (AH) (83.3%) compared with other muscles. There were 24 cases with amplitude deterioration: during exposure in 6, screwing in 2, and decompression in 16. No deterioration occurred during rod placement. There were 13 (39%) with postoperative motor deficits. Significantly lower rates of amplitude appearance occurred in cases with BMI, positive PST, modified McCormick scale IV, and preoperative JOA score. CONCLUSIONS: AH muscles were particularly useful for functional assessment of corticospinal conduction. High BMI, positive PST, modified McCormick scale IV, and low preoperative JOA score were associated with low rates of amplitude appearance. Amplitude deteriorations occurred throughout surgery, except during rod placement, and speedy rigid rod placement is important.

Surgical intervention for a pediatric isolated intramedullary spinal aneurysm.

PURPOSE: To report the case of a pediatric patient with intramedullary spinal aneurysm. METHODS: A 9-year-old boy presented with low back pain and subsequent gait disturbance. He had no history of trauma. After admission, MRI revealed an intramedullary spinal cord mass lesion surrounded by hemorrhage at the cervical-thoracic junction. Initial treatment was started with intravenous methylprednisolone and bed rest. Neurological deficit disappeared under careful observation for a few months. Surgical intervention was applied for diagnosis and resection of the mass lesion to prevent recurrent hemorrhage. RESULTS: Intraoperative ultrasound sonography helped to diagnose the lesion as a spinal cord aneurysm, prior to midline myelotomy. Monitoring of transcranial muscle evoked potentials helped to avoid spinal cord damage during surgery. There has been no evidence of spinal aneurysm on MRI for 3 years after surgery and no neurological deterioration. CONCLUSION: To our knowledge, this is a first report of an intramedullary spinal cord aneurysm at the cervical-thoracic junction in a pediatric patient. Careful observation after initial symptoms followed by surgical intervention was favorable in this case.

＜Editors' Choice＞ Surgical outcomes of decompressive laminoplasty with spinous process osteotomy to treat lumbar spinal stenosis.

Decompressive laminoplasty with spinous process osteotomy (LSPO) was developed as a less invasive procedure for lumbar decompression by Weiner et al. There are few reports extensively highlighting the surgical outcomes of LSPO. The purpose of this study was to evaluate the surgical outcomes of LSPO for lumbar spinal stenosis (LSS). In total, 23 patients with LSS were studied. All patients were followed up for more than 2 years. The Japanese Orthopedic Association (JOA) scores, the recovery rate (RR) of JOA scores, Visual analog scale (VAS) scores, responses to the JOA Back Pain Evaluation Questionnaire (JOABPEQ), sagittal alignment and segmental motion following LSPO were assessed preoperatively and 2 years postoperatively. Postoperative paravertebral muscle atrophy and bone union rates between the spinous process and the residual laminae were assessed. Preoperative and 2-year postoperative JOA scores were 13.0 points and 24.7 points, respectively (p<0.001). With respect to JOABPEQ, significant improvements were observed in pain-related disorders (p<0.05), walking ability (p<0.01), social life function (p<0.05), and mental health (p<0.05) dimensions. There were no significant differences between preoperative and 2-year postoperative sagittal alignment and range of motion. The degree of the paravertebral muscle atrophy at 2 years postoperatively was 23.0 % at spread side and 9.6 % at nonspread side (p<0.01). The fusion rate of the spinous process with the arcus vertebrae was 87%. This result reveals that LSPO could acquire the reconstruction of posterior supporting structures. We demonstrated that LSPO could be a one of the surgical options for LSS.