Importance of physiological age in determining indications for adult spinal deformity surgery in patients over 75 years of age: a propensity score matching analysis.

PURPOSE: Physiologically, people age at different rates, which leads to a discrepancy between physiological and chronological age. Physiological age should be a priority when considering the indications for adult spinal deformity (ASD) surgery. The primary objective of this study was to determine the characteristics of the postoperative course, surgical outcomes, and complication rates to extend the healthy life expectancy of older ASD patients (≥ 75 years). The secondary objective was to clarify the importance of physiological age in the surgical treatment of older ASD patients, considering frailty. METHODS: A retrospective review of 109 consecutive patients aged ≥ 65 years with symptomatic ASD who underwent a corrective long fusion with lateral interbody fusion from the lower thoracic spine to the pelvis from 2015 to 2019 was conducted. Patients were classified into two groups according to age (group Y [65-74 years], group O [≥ 75 years]) and further divided into four groups according to the ASD-frailty index score (Y-F, Y-NF, O-F, and O-NF groups). To account for potential risk factors for perioperative course characteristics, complication rates, and surgical outcomes, patients from the database were subjected to propensity score matching based on sex, BMI, and preoperative sagittal spinal alignment (C7 sagittal vertical axis, pelvic incidence-lumbar lordosis, and pelvic tilt). Clinical outcomes were evaluated 2 years postoperatively, using three patient-reported outcome measures of health-related quality of life: the Oswestry Disability Index, Scoliosis Research Society questionnaire (SRS-22), and Short Form 36 (SF-36). Additionally, the postoperative time-to-first ambulation, as well as minor, major, and mechanical complications, were evaluated. RESULTS: In the comparison between Y and O groups, patients in group O were at a higher risk of minor complications (delirium and urinary tract infection). In contrast, other surgical outcomes of group O were comparable to those of group Y, except for SRS-22 (satisfaction) and time to ambulation after surgery, with better outcomes in Group O. Patients in the O-NF group had better postoperative outcomes (time to ambulation after surgery, SRS-22 (function, self-image, satisfaction), SF-36 [PCS]) than those in the Y-F group. CONCLUSIONS: Older age warrants monitoring of minor complications in the postoperative management of patients. However, the outcomes of ASD surgery depended more on frailty than on chronological age. Older ASD patients without frailty might tolerate corrective surgery and have satisfactory outcomes when minimally invasive techniques are used. Physiological age is more important than chronological age when determining the indications for surgery in older patients with ASD.

Supervised physical therapy versus surgery for patients with lumbar spinal stenosis: a propensity score-matched analysis.

BACKGROUND: Previous studies comparing surgical with nonsurgical treatment for lumbar spinal stenosis (LSS) reported that surgery is superior to nonsurgical treatments, but intensive and adequate volume of physical therapy were rarely performed. The purpose of this study was to compare the 1-year follow-up outcomes of patients with LSS treated with supervised physical therapy or surgery using propensity score-matched analysis. METHODS: A total of 224 patients with LSS who received supervised physical therapy (n = 38) or surgery (n = 186) were included, of which 66 were matched on baseline demographics, radiological findings, and patient-reported outcomes. The physical therapy group received supervised physical therapy twice weekly for 6 weeks. The physical therapy sessions included manual therapy, individually tailored exercises, cycling, and body-weight supported treadmill walking. The surgery group underwent decompression surgery with or without spinal fusion. A propensity score analysis was performed using a one-to-one nearest neighbor approach. RESULTS: The surgery group showed greater improvements in Zurich claudication questionnaire symptom severity and physical function, SF-36 physical functioning, bodily pain, and mental health, but had more severe stenosis and symptoms and mental health problems than the physical therapy group at baseline (P <  0.05). After propensity score matching, there were no significant differences in baseline characteristics, and all clinical outcomes at 1 year, except for a higher percentage of responders achieving minimum clinically important difference in the role-emotional subscale of SF-36 in the surgery group (P <  0.05). CONCLUSIONS: When baseline characteristics were considered, supervised physical therapy yielded similar effects to lumbar surgery. These results suggest that supervised physical therapy is preferred over surgery as first-choice treatment, to prevent complications and to minimize health care costs, especially in mild to moderate cases of LSS.

MRI grading of spinal stenosis is not associated with the severity of low back pain in patients with lumbar spinal stenosis.

BACKGROUND: Although lumbar spinal stenosis (LSS) often coexists with other degenerative conditions, few studies have fully assessed possible contributing factors for low back pain (LBP) in patients with LSS. The purpose of this study was to identify factors associated with the severity of LBP in patients with LSS. METHODS: The patients with neurogenic claudication caused by LSS, which was confirmed by magnetic resonance imaging (MRI) were included in this cross-sectional study. Data included ratings of LBP, buttock and leg pain, and numbness on a numerical rating scale (NRS), 36-item Short-Form Survey (SF-36) scores, muscle mass measured by bioelectrical impedance analysis, and radiographic measurements including lumbopelvic alignment and slippage. The severity of LSS, endplate defects, Modic endplate changes, intervertebral disc degeneration, and facet joint osteoarthritis were evaluated on MRI. Spearman correlation and multivariate linear regression analyses were used to examine the factors associated with the severity of LBP (NRS score). RESULTS: A total of 293 patients (135 male and 158 female, average age 72.6 years) were analyzed. LBP was moderately correlated with buttock and leg pain, and buttock and leg numbness. Significant but weak correlations were observed between LBP and body mass index, appendicular and trunk muscle mass, all domains of SF-36, pelvic tilt, total number of endplate defects and Modic endplate changes, and summary score of disc degeneration grading, but not severity or number of spinal stenoses. In the multivariate regression analysis, age, female sex, trunk muscle mass, diabetes, NRS buttock and leg pain, NRS buttock and leg numbness, SF-36 vitality, pelvic tilt, and total number of endplate defects were associated with the severity of LBP. CONCLUSIONS: Trunk muscle mass, lumbopelvic alignment, and endplate defects, but not severity of stenosis are partly associated with severity of LBP, but buttock and leg pain and buttock and leg numbness have strongest relationships with LBP in patients with LSS.

The impact of diabetes mellitus on spinal fracture with diffuse idiopathic skeletal hyperostosis: A multicenter retrospective study.

BACKGROUND: Patients with diffuse idiopathic skeletal hyperostosis (DISH) are susceptible to spinal column injuries with neurological deterioration. Previous studies indicated that the prevalence of diabetes mellitus (DM) in patients with DISH was higher than that in patients without DISH. This study investigates the impact of DM on surgical outcomes for spinal fractures in patients with DISH. METHODS: We retrospectively evaluated 177 spinal fractures in patients with DISH (132 men and 45 women; mean age, 75 ± 10 years) who underwent surgery from a multicenter database. The subjects were classified into two groups according to the presence of DM. Perioperative complications, neurological status by Frankel grade, mortality rate, and status of surgical site infection (SSI) were compared between the two groups. RESULTS: DM was present in 28.2% (50/177) of the patients. The proportion of men was significantly higher in the DM group (DM group: 86.0% vs. non-DM group: 70.1%) (p = 0.03). The overall complication rate was 22.0% in the DM group and 19.7% in the non-DM group (p = 0.60). Poisson regression model revealed that SSI was significantly associated with DM (DM group: 10.0% vs. non-DM group: 2.4%, Relative risk: 4.5) (p = 0.048). Change in neurological status, mortality rate, instrumentation failure, and nonunion were similar between both groups. HbA1c and fasting blood glucose level (SSI group: 7.2% ± 1.2%, 201 ± 67 mg/dL vs. non-SSI group: 6.6% ± 1.1%, 167 ± 47 mg/dL) tended to be higher in patients with SSI; however, there was no significant difference. CONCLUSIONS: In spinal fracture in patients with DISH, although DM was an associated factor for SSI with a relative risk of 4.5, DM did not negatively impact neurological recovery. Perioperative glycemic control may be useful for preventing SSI because fasting blood glucose level was high in patients with SSI.

Supervised physical therapy versus unsupervised exercise for patients with lumbar spinal stenosis: 1-year follow-up of a randomized controlled trial.

OBJECTIVE: To compare the 1-year outcomes of patients with lumbar spinal stenosis treated with supervised physical therapy or unsupervised exercise. DESIGN: A single-center randomized controlled trial with concealed allocation, blinded assessor and intention-to-treat analysis. SETTING: Spine care center. SUBJECTS: A total of 86 patients presenting with symptoms of neurogenic claudication caused by lumbar spinal stenosis. INTERVENTIONS: The physical therapy group received supervised physical therapy sessions twice a week for 6 weeks and home exercise program. The home exercise group received 6-week home exercise program only. MAIN MEASURES: The primary outcome was symptom severity on the Zurich claudication questionnaire at 1 year. Secondary outcomes included physical function, pain, health-related quality of life and the surgery rate after 1 year. RESULTS: At 1 year, more patients in the physical therapy group than in the home exercise group achieved minimum clinically important differences in Zurich claudication questionnaire symptom severity (60.5% vs 32.6%; adjusted odds ratio [AOR] 4.3, [95% CI [1.5-12.3], P = 0.01); Zurich claudication questionnaire physical function (55.8% vs 32.6%; AOR 3.0 [1.1-8.1], P = 0.03); SF-36 bodily pain (48.8% vs 25.6%; AOR 2.8 [1.1-7.3], P = 0.03), and SF-36 general health (20.9% vs 7.0%; AOR 6.1 [1.1-33.0], P = 0.04). The surgery rate at 1 year was lower in the physical therapy than in the home exercise group (7.0% vs 23.3%; AOR 0.2 [0.04-0.9] P = 0.04). CONCLUSIONS: Supervised physical therapy produced greater improvements in symptom severity and physical function than unsupervised exercise and was associated with lower likelihood of receiving surgery within 1 year.

A nationwide survey on the incidence and characteristics of traumatic spinal cord injury in Japan in 2018.

STUDY DESIGN: Retrospective epidemiological study. OBJECTIVES: Since the causes and incidences of traumatic spinal cord injury (TSCI) in each country change over time, up-to-date epidemiological studies are required for countermeasures against TSCI. However, no nationwide survey in Japan has been conducted for about 30 years. The purpose of this study was therefore to investigate the recent incidence and characteristics of TSCI in Japan. SETTING: Japan METHODS: Survey sheets were sent to all hospitals (emergency and acute care hospitals) that treated TSCI persons in Japan in 2018 and case notes were retrospectively reviewed. Frankel grade E cases were excluded from analysis. RESULTS: The response rate was 74.4% (2804 of 3771 hospitals). The estimated annual incidence of TSCI excluding Frankel E was 49 per million, with a median age of 70.0 years and individuals in their 70s as the largest age group. Male-to-female ratio was 3:1. Cervical cord injuries occurred in 88.1%. Frankel D was the most frequent grade (46.3%), followed by Frankel C (33.0%). The most frequent cause was fall on level surface (38.6%), followed by traffic accident (20.1%). The proportion of fall on level surface increased with age. TSCI due to sports was the most frequent cause in teenagers (43.2%). CONCLUSIONS: This nationwide survey in Japan showed that estimated incidence of TSCI, rate of cervical cord injury, and incomplete injury by falls appear to be increasing with the aging of the population.

Improving effect of microendoscopic decompression surgery on low back pain in patients with lumbar spinal stenosis and predictive factors of postoperative residual low back pain: a single-center retrospective study.

BACKGROUND: Although there are reports on the effectiveness of microendoscopic laminotomy using a spinal endoscope as decompression surgery for lumbar spinal stenosis, predicting the improvement of low back pain (LBP) still poses a challenge, and no clear index has been established. This study aimed to investigate whether microendoscopic laminotomy for lumbar spinal stenosis improves low back pain and determine the preoperative predictors of residual LBP. METHODS: In this single-center retrospective study, we examined 202 consecutive patients who underwent microendoscopic laminotomy for lumbar spinal stenosis with a preoperative visual analog scale (VAS) score for LBP of ≥40 mm. The lumbar spine Japanese Orthopaedic Association (JOA), and VAS scores for LBP, leg pain (LP), and leg numbness (LN) were examined before and at 1 year after surgery. Patients with a 1-year postoperative LBP-VAS of ≥25 mm composed the residual LBP group. The preoperative predictive factors associated with postoperative residual LBP were analyzed. RESULTS: JOA scores improved from 14.1 preoperatively to 20.2 postoperatively (p < 0.001), LBP-VAS improved from 66.7 to 29.7 mm (p < 0.001), LP-VAS improved from 63.8 to 31.2 mm (p < 0.001), and LN-VAS improved from 63.3 to 34.2 mm (p < 0.001). Ninety-eight patients (48.5%) had a postoperative LBP-VAS of ≥25 mm. Multiple logistic regression analysis revealed that Modic type 1 change (odds ratio [OR], 5.61; 95% confidence interval [CI], 1.68-18.68; p = 0.005), preoperative VAS for LBP ≥ 70 mm (OR, 2.19; 95% CI, 1.17-4.08; p = 0.014), and female sex (OR, 1.98; 95% CI, 1.09-3.89; p = 0.047) were preoperative predictors of residual LBP. CONCLUSION: Microendoscopic decompression surgery had an ameliorating effect on LBP in lumbar spinal stenosis. Modic type 1 change, preoperative VAS for LBP, and female sex were predictors of postoperative residual LBP, which may be a useful index for surgical procedure selection.

Sagittal imbalance of the spine-pelvis-lower extremity axis associated with back-related disability.

BACKGROUND: The impact of sagittal imbalance in patients has been reported in LBP and LBP-related disabilities due to spinopelvic imbalance. However, no reports investigating the spine-pelvis-lower extremity axis using lateral images have been reported thus far. This study introduced a novel parameter of the spine-pelvis-lower extremity axis and evaluated whether this parameter was related to symptoms. METHODS: A total of 343 subjects were included in this cross-sectional study. Standing spine-pelvis and pelvis-lower extremity radiographs were obtained to assess the sagittal vertical axis (SVA), pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), lumbar lordosis, and thoracic kyphosis. The sacral-knee distance (SKD) (i.e., distance from the anterior femoral condyle to the vertical axis at the upper posterior edge of S1 body) was measured. Furthermore, the SVA/SKD ratio was calculated for global balance. Subjects were divided into leg compensated (LC; SVA/SKD ratio <0.8) and decompensated (LD; SVA/SKD ratio ≥0.8) groups. The SVA was divided into balanced spine (BS; SVA ≤40 mm) and imbalanced spine (IS; SVA >40 mm) groups. All individuals were classified into LC + BS, LC + IS, LD + BS, and LD + IS groups. The relationships among the four groups and low back pain (LBP), Oswestry Disability Index (ODI), and knee pain were examined. RESULTS: SKD was significantly correlated with SVA, SS, PI, PT, and knee-femoral angle. ODI was significantly higher in the LC + IS group than in the LD + BS group (p < 0.05). Knee pain prevalence was significantly higher in the LC + IS and LC + BS groups than in the LD + IS group (p < 0.05). CONCLUSION: SVA/SKD ratio is useful for evaluating global alignment. Our findings are significant because they highlight the importance of SKD with respect to knee pain, LBP, and LBP- related disabilities.

Risk factors for delayed diagnosis of spinal fracture associated with diffuse idiopathic skeletal hyperostosis: A nationwide multiinstitution survey.

BACKGROUND: Patients with DISH are susceptible to spinal fractures and subsequent neurological impairment, including after minor trauma. However, DISH is often asymptomatic and fractures may have minimal symptoms, which may lead to delayed diagnosis. The purpose of this study was to identify risk factors for delayed diagnosis of spinal fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: The subjects were 285 patients with DISH surgically treated at 18 medical centers from 2005 to 2015. Cause of injury, imaging findings, neurological status at the times of injury and first hospital examination, and the time from injury to diagnosis were recorded. A delayed diagnosis was defined as that made >24 h after injury. RESULTS: Main causes of injury were minor trauma due to a fall from a standing or sitting position (51%) and high-energy trauma due to a fall from a high place (29%) or a traffic accident (12%). Delayed diagnosis occurred in 115 patients (40%; 35 females, 80 males; mean age 76.0 ± 10.4 years), while 170 (60%; 29 females, 141 males; mean age 74.6 ± 12.8 years) had early diagnosis. Delayed group had a significantly higher rate of minor trauma (n = 73, 63% vs. n = 73, 43%), significantly more Frankel grade E (intact neurological status) cases at the time of injury (n = 79, 69% vs. n = 73, 43%), and greater deterioration of Frankel grade from injury to diagnosis (34% vs. 8%, p < 0.01). In multivariate analysis, a minor trauma fall (OR 2.08; P < 0.05) and Frankel grade E at the time of injury (OR 2.29; P < 0.01) were significantly associated with delayed diagnosis. CONCLUSION: In patients with DISH, it is important to keep in mind the possibility of spinal fracture, even in a situation in which patient sustained only minor trauma and shows no neurological deficit. This is because delayed diagnosis of spinal fracture can cause subsequent neurological deterioration.

Preoperative psychological factors affecting surgical satisfaction of elderly patients with lumbar spinal stenosis.

OBJECTIVE: The objective of this observational study was to investigate the effects of preoperative psychological factors on short-term patient satisfaction with surgery in elderly patients with lumbar spinal stenosis (LSS). METHODS: Surgery was performed on 90 elderly patients with clinically and radiologically defined LSS: mean age at surgery, 73 years; 46 men and 44 women. Patients completed questionnaires before surgery and 1 year postoperatively. They used a self-administered the Roland Morris Disability Questionnaire (RDQ), the Japanese Orthopaedic Association Back Pain Questionnaire (JOABPEQ), MOS 36-Item Short-Form Health Survey (SF-36), and satisfaction for surgery (VAS) were completed. At baseline, psychological factors were assessed using the Self-Rating Questionnaire for Depression (SRQ-D), Hospital Anxiety and Depression scale (HADS), Pain Catastrophizing Scale (PCS), Pain Anxiety Symptoms Scale-20, and Brief Scale for Psychiatric Problems in Orthopaedic Patients (BS-POP). At follow-up, patient satisfaction was evaluated using 2 items: (1) satisfaction with surgery and (2) Would you undergo the same surgery again?. RESULTS: Satisfaction item 1 correlated negatively with the VAS for low back pain, leg pain, numbness, JOABPEQ social life disturbance score, SF-36 physical function score, and HADS anxiety score (p < 0.05). Satisfaction 2 correlated negatively with age at surgery, VAS of leg pain, PCS magnification score, and BS-POP score (p < 0.05). Multiple regression analysis showed significant associations between satisfaction 1 and SF-36 physical function and HADS anxiety scores, and between satisfaction 2 and PCS magnification score (p < 0.05). STATISTICAL ANALYSIS: The preoperative factors independently associated with surgical satisfaction were analyzed utilizing Speaman's rank correlation coefficient and multiple regression analysis. CONCLUSION: Physical function and anxiety were identified as preoperative factors that affected patient satisfaction with surgery. Preoperative assessment of psychological factors and interventions for anxiety may help improve patient satisfaction after surgery for LSS.

Physical performance decreases in the early stage of cervical myelopathy before the myelopathic signs appear: the Wakayama Spine Study.

PURPOSE: We previously revealed a prevalence rate of 24.4% for cervical cord compression (CCC) in a population-based magnetic resonance imaging study. This study aimed to investigate the occurrence of cervical myelopathy (CM) among CCC cases and to reveal the predictors for CM. METHODS: This study is a part of "The Wakayama Spine Study," a large-scale population-based MRI cohort study. At baseline, 238 patients were diagnosed with CCC. We followed 238 patients who had CCC for more than 4 years, of which 158 (mean age, 68.9 years) participated in the second survey (follow-up rate, 66.3%). In the second survey, de novo CM was defined clinically as the presence of myelopathic signs (e.g., Hoffmann reflex, hyperreflexia of the patellar tendon, and Babinski reflex). Physical performance on 10-s grip and release test (GRT), grip strength, 6-m walking time at a usual and a maximal pace, step length at a usual and a maximal pace, chair stand time (CST), and one-leg standing (OLS) time was measured. RESULTS: Among the 158 participants, nine (mean age, 68.8 years; incidence rate, 6.3%) were newly diagnosed with CM in the second survey. CST, 6-m walking time at a usual and a maximal pace, and step length at a maximal pace had already decreased in the de novo CM (+) participants at baseline compared to baseline findings of de novo (-) CM participants, but not the grip strength, OLS, or GRT. CONCLUSIONS: We clarified the incidence rate of CM in CCC patients and the predictors of de novo CM. These slides can be retrieved under Electronic Supplementary Material.

A comparative study of gait characteristics associated with and without degenerative lumbar spondylolisthesis in patients with lumbar spinal stenosis.

BACKGROUND: Reported characteristics of DS include forward slippage of the superior lumbar relative to the inferior lumbar, lumbar instability, increased lumbar lordotic angle, and high body mass index (BMI). However, to our knowledge, only static measurements were conducted in previous studies, and no dynamic observations exist. In this crosssectional study, the gait of patients with and without DS in LSS was compared, and their characteristics were examined using a three-dimensional motion analysis system. METHODS: In total, 42 patients with LSS were included. Lumbar lordosis angle, sacral tilt angle, lumbar slip rate determined from X-ray images, the Zurich Claudication Questionnaire (ZCQ), the visual analog scale (VAS), and BMI were evaluated. U-COM length was the distance between the upper center of mass (COM) and the body's COM, while L-COM length was the distance between the lower COM and the COM. Each DS and Non-DS group evaluation was compared using the Mann-Whitney U-test. Additionally, multivariate analysis was performed using factors with significant differences as explanatory variables and with or without DS as the target variable. RESULTS: Lumbar lordotic angle was significantly higher in the DS group and there was a significant difference between U-COM and L-COM lengths in the sagittal planes at heel contact (HC) and toe-off (TO). L-COM length at HC and TO was a significant variable when the lumbar lordotic angle was adjusted as a confounding factor in multivariate analysis. CONCLUSIONS: The U-COM and L-COM lengths in the DS group were both extended and the line connecting each COM was inclined backward on the sagittal plane at HC and TO during gait. Our study showed that L-COM length was associated with or without DS.

Spinal fractures in patients with Diffuse idiopathic skeletal hyperostosis:A nationwide multi-institution survey.

BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) increases the spine's susceptibility to unstable fractures that can cause neurological deterioration. However, the detail of injury is still unclear. A nationwide multicenter retrospective study was conducted to assess the clinical characteristics and radiographic features of spinal fractures in patients with DISH. METHODS: Patients were eligible for this study if they 1) had DISH, defined as flowing ossification along the anterolateral aspect of at least four contiguous vertebral bodies, and 2) had an injury in the ankylosing spine. This study included 285 patients with DISH (221 males, 64 females; mean age 75.2 ± 9.5 years). RESULTS: The major cause of injury was falling from a standing or sitting position; this affected 146 patients (51.2%). Diagnosis of the fracture was delayed in 115 patients (40.4%). Later neurological deterioration by one or more Frankel grade was seen in 87 patients (30.5%). The following factors were significantly associated with neurological deficits: delayed diagnosis (p = 0.033), injury of the posterior column (p = 0.021), and the presence of ossification of the posterior longitudinal ligament (OPLL) (p < 0.001). The majority of patients (n = 241, 84.6%) were treated surgically, most commonly by conventional open posterior fixation (n = 199, 69.8%). Neurological improvement was seen in 20.0% of the conservatively treated patients, and in 47.0% of the patients treated surgically. CONCLUSIONS: Minor trauma could cause spinal fractures in DISH patients. Delayed diagnosis, injury of the posterior column, and the presence of OPLL were significantly associated with neurological deterioration. Patients with neurological deficits or unstable fractures should be treated by fixation surgery.

Can postoperative deltoid weakness after cervical laminoplasty be prevented by using intraoperative neurophysiological monitoring?

Laminoplasty, frequently performed in patients with cervical myelopathy, is safe and provides relatively good results. However, motor palsy of the upper extremities, which occurs after decompression surgery for cervical myelopathy, often reduces muscle strength of the deltoid muscle, mainly in the C5 myotome. The aim of this study was to investigate prospectively whether postoperative deltoid weakness (DW) can be predicted by performing intraoperative neurophysiological monitoring (IONM) during cervical laminoplasty and to clarify whether it is possible to prevent palsy using IONM. We evaluated the 278 consecutive patients (175 males and 103 females) who underwent French-door cervical laminoplasty for cervical myelopathy under IONM between November 2008 and December 2016 at our hospital. IONM was performed using muscle evoked potential after electrical stimulation to the brain [Br(E)-MsEP] from the deltoid muscle. Seven patients (2.5%) developed DW after surgery (2 with acute and 5 with delayed onset). In all patients, deltoid muscle strength recovered to ≥ 4 on manual muscle testing 3-6 months after surgery. Persistent IONM alerts occurred in 2 patients with acute-onset DW. To predict the acute onset of DW, Br(E)-MsEP alerts in the deltoid muscle had both a sensitivity and specificity of 100%. The PPV of persistent Br(E)-MsEP alerts had both a sensitivity and specificity of 100% for acute-onset DW. There was no change in Br(E)-MsEP in patients with delayed-onset palsy. The incidence of deltoid palsy was relatively low. Persistent Br(E)-MsEP alerts of the deltoid muscle had a 100% sensitivity and specificity for predicting a postoperative acute deficit. IONM was unable to predict delayed-onset DW. In only 1 patient were we able to prevent postoperative DW by performing a foraminotomy.

A comparative study of 2-year follow-up outcomes in lumbar spinal stenosis patients treated with physical therapy alone and those with surgical intervention after less successful physical therapy.

BACKGROUND: The efficacy of physical therapy for patients with lumbar spinal stenosis (LSS) has been reported only for the short term, and few reports have compared outcomes of surgical treatment with nonsurgical treatment after physical therapy. The purpose of this study was to assess 2-year outcomes of LSS patients treated with surgery or under follow-up observation after physical therapy for 6 weeks. METHODS: Patients presenting with neurogenic claudication, radiologically-confirmed central LSS affecting both legs and refractory symptoms to pharmacotherapy of more than 3 months were enrolled. Patients were treated with manual therapy, stretching and strengthening exercises, and body weight-supported treadmill walking once a week for 6 weeks. Clinical outcomes were measured using the Zurich Claudication Questionnaire (ZCQ), visual analog scale of low back pain, leg pain, and numbness, the Japanese Orthopedic Association Back Pain Evaluation Questionnaire and the SF-36. Two years after physical therapy, patients were classified into the observation group (Group I) or the surgery group (Group II), whose patients failed to respond to physical therapy and wanted to undergo surgery. RESULTS: Thirty-eight patients were enrolled; 28 had complete data at 2 years: 21 and 7 in Groups I and II, respectively. Group II had a higher body mass index (BMI) than Group I. There were no significant differences in clinical outcomes at baseline. Six weeks after physical therapy, Group I had significantly better outcomes for symptom severity and physical function on the ZCQ subscales, physical functioning and bodily pain on the SF-36 subscales. These outcomes in Group I were maintained or improved and did not differ significantly between groups at 2-years. However, the physical function on the ZCQ subscales was improved in Group II more than those in Group I (mean difference -0.6; 95% CI: -1.2 to -0.03, P < 0.05) at 2 years. CONCLUSIONS: At 2 years, the outcomes except for the change in physical function score in the ZCQ subscale did not differ significantly between patients who had undergone surgery and those who avoided surgery.

Minimally invasive decompression surgery for lumbar spinal stenosis with degenerative scoliosis: Predictive factors of radiographic and clinical outcomes.

There is ongoing controversy regarding the most appropriate surgical treatment for lumbar spinal stenosis (LSS) with concurrent degenerative lumbar scoliosis (DLS): decompression alone, decompression with limited spinal fusion, or long spinal fusion for deformity correction. The coexistence of degenerative stenosis and deformity is a common scenario; Nonetheless, selecting the appropriate surgical intervention requires thorough understanding of the patients clinical symptomatology as well as radiographic parameters. Minimally invasive (MIS) decompression surgery was performed for LSS patients with DLS. The aims of this study were (1) to investigate the clinical outcomes of MIS decompression surgery in LSS patients with DLS, and (2) to identify the predictive factors for both radiographic and clinical outcomes after MIS surgery. 438 consecutive patients were enrolled in this study. Inclusion criteria was evidence of LSS and DLS with coronal curvature measuring greater than 10°. The Japanese Orthopaedic Association (JOA) score, JOA recovery rate, low back pain (LBP), and radiographic features were evaluated preoperatively and at over 2 years postoperatively. Of the 438 patients, 122 were included in final analysis, with a mean follow-up of 2.4 years. The JOA recovery rate was 47.6%. LBP was significantly improved at final follow-up. Cobb angle was maintained for 2 years postoperatively (p = 0.159). Clinical outcomes in foraminal stenosis patients were significantly related to sex, preoperative high Cobb angle and progression of scoliosis (p = 0.008). In the severe scoliosis patients, the JOA recovery was 44%, and was significantly depended on progression of scoliosis (Cobb angle: preoperation 29.6°, 2-years follow-up 36.9°) and mismatch between the pelvic incidence (PI) and the lumbar lordosis (LL) (preoperative PI-LL 35.5 ± 21.2°) (p = 0.028). This study investigated clinical outcomes of MIS decompression surgery in LSS patients with DLS. The predictive risk factors of clinical outcomes were severe scoliosis, foramina stenosis, progressive scoliosis and large mismatch of PI-LL.

Efficacy and safety of novel high-frequency multi-train stimulation for recording transcranial motor evoked potentials in a rat model.

Recently, low-frequency multi-train stimulation (MTS) was shown to effectively enhance transcranial motor-evoked potentials (TcMEPs). In contrast, high- frequency double-train stimulation was reported to elicit a marked facilitation. The aim of this study was to evaluate the efficacy of high-frequency MTS in the augmentation of potentials. In addition, we investigated the safety of high-frequency MTS, behaviorally and histologically. TcMEPs were recorded from the triceps surae muscle in 38 rats. A multipulse stimulus was delivered repeatedly at different rates (2, 5, 10, 20, and 50 Hz), and was defined as MTS. A conditioned taste aversion method was used to investigate the effect of high-frequency MTS on learning and memory function. Subsequently, animals were sacrificed, and the brains were removed and examined using the standard hematoxylin-eosin method. Compared with conventional single train stimulation, TcMEP amplitudes increased 1.3, 2.1, 1.9, and 2.0 times on average with 5, 10, 20, and 50 Hz stimulation, respectively. The aversion index was >0.8 in all animals after they received 100 high-frequency MTSs. Histologically, no pathological changes were evident in the rat brains. High-frequency MTS shows potential to effectively enhance TcMEP responses, and to be used safely in transcranial brain stimulation.

Clinical outcomes after microendoscopic laminotomy for lumbar spinal stenosis: a 5-year follow-up study.

PURPOSE: To prospectively investigate the long-term clinical outcomes of microendoscopic laminotomy (MEL) in patients with lumbar spinal stenosis (LSS) with and without degenerative spondylolisthesis (DS). METHODS: In total, 159 patients (mean age, 68 years) who had undergone MEL for single-level LSS at L4/5 at our institute were recruited and followed-up for 5 years. Patients with and without DS were assigned to the DS (n = 71) and control (n = 88) groups, respectively. In addition to slippage rate, Japanese orthopedic association (JOA), recovery rate, short-form 36 (SF-36), and Roland-Morris disability questionnaire (RDQ) values were evaluated preoperatively and 5 years postoperatively. All parameters were analyzed by Student's t test, with p < 0.05 considered statistically significant. RESULTS: Of 159 patients, 12 were lost to follow-up (follow-up rate, 92.5%); moreover, 15 patients were excluded because of death, cerebral infarction, dementia, or terminal cancer. Thus, 132 patients (DS group: 61, control group: 71) were finally examined. No significant differences were found in preoperative JOA, JOA recovery rate, RDQ, and SF-36 values between groups. The slippage rate in the DS group was 18.1% preoperatively and 16.8% at 5 years postoperatively (p > 0.05). There was no significant increase in instability in those with DS following MEL. Progressive spinal instability was noted in six patients (9.8%) and five patients (7.0 %) in the DS and control groups, respectively (p > 0.05). Moreover, the success rate of MEL was good/excellent in 70%, fair in 20%, and poor in 10 % of patients in both groups. CONCLUSION: MEL showed similar outcomes in patients with DS and in those without DS.

Improved accuracy of diagnosis of lumbar intra and/or extra-foraminal stenosis by use of three-dimensional MR imaging: comparison with conventional MR imaging.

BACKGROUND: The purposes of this study were to assess the reliability of 3-dimensional magnetic resonance (MR) imaging (3D MRI) and conventional MRI (CMRI) for detection of lumbar intra and/or extra-foraminal stenosis (LIEFS) and to compare the diagnostic accuracy of the 2 imaging modalities. METHODS: A total of 60 sets of 3D MR and CMR images from 20 healthy volunteers and 40 LIEFS patients were qualitatively rated according to defined criteria by 3 independent, blinded readers. Kappa statistics were used to characterize intra and inter-reader reliability for qualitative rating of data. Multireader, multicase analysis was used to compare lumbar foraminal stenosis detection between the 2 modalities. RESULTS: Intra-reader agreement for 3D MRI was excellent, with kappa = 0.90; that for CMRI was good, with kappa = 0.78. Average inter-reader agreement for 3D MRI was good, with kappa = 0.79, whereas that for CMRI was moderate, with kappa = 0.41. Average area under the ROC curve values (1st reading/2nd reading) for detection of lumbar foraminal stenosis using 3D MRI and CMRI were 0.99/0.99 and 0.94/0.92, respectively. Detection of LIEFS with 3D MRI was significantly better than with CMRI (P = 0.0408/0.0294). CONCLUSIONS: These results suggest that CMRI was of limited use for detection of the presence of LIEFS. Isolated imaging with CMRI may risk overlooking the presence of LIEFS. In contrast, reliability of 3D MRI for detection of LIEFS was good. Furthermore, readers' performance in the diagnosis of LIEFS can be improved by use of 3D MRI. Therefore, 3D MRI is recommended when using imaging for diagnosis of LIEFS.

Development of a support tool for the clinical diagnosis of symptomatic lumbar intra- and/or extra-foraminal stenosis.

BACKGROUND: Not all lumbar intra- and/or extra-foraminal stenosis (LIEFS) on MRI is symptomatic. Therefore, the establishment of clinical diagnostic tools that can identify patients with symptomatic LIEFS is crucial in the clinical setting. The aim of this study was to develop a support tool for clinical diagnosis of LIEFS. METHODS: Patients with L5 radiculopathy alone were prospectively enrolled. Fifty-one patients with lumbar spinal canal stenosis only at the L4-5 level and 49 patients with LIEFS only at the L5-S1 level were extracted from this cohort. We compared the two groups with regard to 12 variables--three subjective and three objective items from the Japanese Orthopaedic Association (JOA) score; Kemp's sign; results of the lumbar flexion test, Bonnet test, and Freiberg test; pain on sitting; and pain when recumbent--to determine which factors were associated with a high index of clinical suspicion of LIEFS. RESULTS: The significant predictors of a final diagnosis of LIEFS were identified as follows: pain when recumbent, Freiberg and Bonnet test results, and pain on sitting. To develop a diagnostic tool, a scoring system (0-20 points) was formulated on the basis of the contribution ratios of these risk factors. To determine the contribution ratio, an integer score was assigned to the identified risk factors as follows: pain when recumbent = 9 points, Freiberg = 5 points, Bonnet = 3 points, and pain on sitting = 3 points. The Hosmer-Lemeshow statistic for this scoring system was p = 0.063, and confirmed that it was a good model. Receiver operating characteristic (ROC) curve analysis demonstrated a cut-off value of 5 points, an area under the ROC curve of 0.87435, sensitivity of 75.5 %, and specificity of 82.3 %. CONCLUSIONS: We believe that the use of this tool in the clinical setting will improve the accuracy of diagnosing symptomatic LIEFS, which will lead to improved quality of patient care.