Takeshi Oichi

Validity and Reliability of the Japanese Version of the painDETECT Questionnaire: A Multicenter Observational Study

Objectives The aim of this study was to evaluate the validity and reliability of the Japanese version of the painDETECT questionnaire (PDQ-J). Materials and Methods The translation of the original PDQ into Japanese was achieved according to the published guidelines. Subsequently, a multicenter observational study was performed to evaluate the validity and reliability of PDQ-J, including 113 Japanese patients suffering from pain. Results Factor analysis revealed that the main component of PDQ-J comprises two determinative factors, which account for 62% of the variance observed. Moreover, PDQ-J revealed statistically significant correlation with the intensity of pain (Numerical Rating Scale), Physical Component Score, and Mental Component Score of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). The Cronbach alpha for the total score was 0.78 and for the main component was 0.80. In the analysis of test–retest method, the intraclass correlation coefficient between the two scores was 0.94. Conclusions We demonstrated the validity and reliability of PDQ-J. We encourage researchers and clinicians to use this tool for the assessment of patients who suffer suspected neuropathic pain.

Mortality and morbidity after spinal surgery in patients with Parkinson's disease: a retrospective matched-pair cohort study

BACKGROUND CONTEXT There is a lack of information about postoperative outcomes and related risk factors associated with spinal surgery in patients with Parkinsons disease (PD). PURPOSE This study aimed to investigate the postoperative morbidity and mortality associated with spinal surgery for patients with PD, and the risk factors for poor outcomes. STUDY DESIGN This is a retrospective matched-pair cohort study. PATIENT SAMPLE Data of patients who underwent elective spinal surgery between July 2010 and March 2013 were extracted from the Diagnosis Procedure Combination database, a nationwide inpatient database in Japan. OUTCOME MEASURES In-hospital mortality and occurrence of postoperative complications. METHODS For each patient with PD, we randomly selected up to four age- and sex-matched controls in the same hospital in the same year. The differences in in-hospital mortality and occurrence of postoperative complications were compared between patients with PD and controls. A multivariable logistic regression model fitted with a generalized estimation equation was used to identify significant predictors of major complications (surgical site infection, sepsis, pulmonary embolism, respiratory complications, cardiac events, stroke, and renal failure). Multiple imputation was used for missing data. RESULTS Among 154,278 patients undergoing spinal surgery, 1,423 patients with PD and 5,498 matched controls were identified. Crude in-hospital mortality was higher in patients with PD than in controls (0.8% vs. 0.3%, respectively). The crude proportion of major complications was also higher in patients with PD (9.8% vs. 5.1% in controls). Postoperative delirium was more common in patients with PD (30.3%) than in controls (4.3%). Parkinsons disease was a significant predictor of major postoperative complications, even after adjusting for other risk factors (odds ratio, 1.74; 95% confidence intervals, 1.37-2.22; p<.001). CONCLUSIONS Patients with PD had a significantly increased risk of postoperative complications following spinal surgery. Postoperative delirium was the most frequently observed complication.

Does the microendoscopic technique reduce mortality and major complications in patients undergoing lumbar discectomy? A propensity score–matched analysis using a nationwide administrative database

OBJECTIVE Although minimally invasive spinal surgery has recently gained popularity, few nationwide studies have compared the adverse events that occur during endoscopic versus open spinal surgery. The purpose of this study was to compare perioperative complications associated with microendoscopic discectomy (MED) and open discectomy for patients with lumbar disc herniation. METHODS The authors retrospectively extracted from the Diagnosis Procedure Combination database, a national inpatient database in Japan, data for patients admitted between July 2010 and March 2013. Patients who underwent lumbar discectomy without fusion surgery were included in the analysis, and those with an urgent admission were excluded. The authors examined patient age, sex, Charlson Comorbidity Index, body mass index, smoking status, blood transfusion, duration of anesthesia, type of hospital, and hospital volume (number of patients undergoing discectomy at each hospital). One-to-one propensity score matching between the MED and open discectomy groups was performed to compare the proportions of in-hospital deaths, surgical site infections (SSIs), and major complications, including stroke, acute coronary events, pulmonary embolism, respiratory complications, urinary tract infection, and sepsis. The authors also compared the hospital length of stay between the 2 groups. RESULTS A total of 26,612 patients were identified in the database. The mean age was 49.6 years (SD 17.7 years). Among all patients, 17,406 (65.4%) were male and 6422 (24.1%) underwent MED. A propensity score-matched analysis with 6040 pairs of patients showed significant decreases in the occurrence of major complications (0.8% vs 1.3%, p = 0.01) and SSI (0.1% vs 0.2%, p = 0.02) in patients treated with MED compared with those who underwent open discectomy. Overall, MED was associated with significantly lower risks of major complications (OR 0.62, 95% CI 0.43-0.89, p = 0.01) and SSI (OR 0.29, 95% CI 0.09-0.87, p = 0.03) than open discectomy. There was a significant difference in length of hospital stay (11 vs 15 days, p < 0.001) between the groups. There was no significant difference in in-hospital mortality between MED and open discectomy. CONCLUSIONS The microendoscopic technique was associated with lower risks for SSI and major complications following discectomy in patients with lumbar disc herniation.

Cervical Anterolisthesis: A Predictor of Poor Neurological Outcomes in Cervical Spondylotic Myelopathy Patients After Cervical Laminoplasty.

Study Design. A retrospective cohort study. Objective. To clarify the influence of cervical spondylolisthesis on neurological outcomes in cervical spondylotic myelopathy (CSM) patients after cervical laminoplasty. Summary of Background Data. Studies focusing on the surgical outcomes in CSM patients with cervical spondylolisthesis are limited. Methods. We retrospectively reviewed 125 CSM patients after cervical laminoplasty. Neurological outcomes were evaluated by calculating the Japanese Orthopedic Association (JOA) recovery rate at 2 years after surgery. We defined anterolisthesis as a more than 3-mm anterior vertebral displacement in a flexion radiograph and retrolisthesis as a more than 3-mm posterior vertebral displacement in an extension radiograph. We further assessed potential risk factors for poor neurological outcomes after cervical laminoplasty, including cervical alignment, degree of spinal cord compression, duration of myelopathic symptoms, diabetes mellitus, and preoperative JOA score. Multivariate logistic regression analysis was performed to investigate the risk factors for poor outcomes (JOA recovery rate <50%) after cervical laminoplasty. Results. Our study included 86 men and 39 women with mean age of 64 (range, 30–89) years. Average JOA scores were 9.9 and 13.3 points before and at 2 years after surgery, respectively. Average recovery rate was 47.2% (range, −68% to 100%), with 62 patients having poor outcomes (JOA recovery rate <50%) at 2 years after surgery. Anterolisthesis and retrolisthesis were observed in 13 and 24 patients, respectively. Multivariate logistic regression analysis revealed that the anterolisthesis was a significant risk factor for poor outcomes (JOA recovery rate <50%) after cervical laminoplasty (P = 0.01), whereas retrolisthesis did not affect the neurological outcomes (P = 0.6). Conclusion. Anterolisthesis, but not retrolisthesis, is a significant risk factor for and predictor of poor neurological outcomes after cervical laminoplasty. Cervical laminoplasty should not be considered in CSM patients with anterolisthesis. Level of Evidence: 2

Psychometric Validation of the Japanese Version of the Neuropathic Pain Symptom Inventory

Objective This study aimed to evaluate the validity and reliability of the Japanese version of the Neuropathic Pain Symptom Inventory (NPSI-J). Design Cross-sectional study design. Subjects and Methods The original Neuropathic Pain Symptom Inventory (NPSI) was translated into Japanese according to published guidelines. Subsequently, an observational study of 60 Japanese patients suffering from neuropathic pain was performed to evaluate the validity and reliability of the NPSI-J. Results The NPSI-J exhibited a statistically significant correlation with pain intensity (Numerical Rating Scale). The Cronbach alpha value for Likert items was 0.86. Using the test–retest analysis method, the intraclass correlation coefficient between the two scores was 0.81. Factor analysis revealed that the main component of NPSI-J comprised three determinative factors. Conclusions The NPSI-J is a reliable and valid pain assessment tool.

Evaluation of Comorbidity Indices for a Study of Patient Outcomes Following Cervical Decompression Surgery: A Retrospective Cohort Study.

Study Design. Retrospective cohort study. Objective. The objective of this study was to investigate the predictive validity of 2 comorbidity indices in a study of patient outcomes following cervical decompression surgery. The comorbidity indices evaluated were the Charlson comorbidity index (CCI) and the self-administered comorbidity questionnaire (SCQ). Summary of Background Data. Comorbidities have been shown to have independent prognostic factors for HRQOL outcome in patients with spinal disorders. However, no appropriate evaluation method of comorbidity has been established in spinal research. Methods. We retrospectively reviewed 86 cervical myelopathy cases treated by decompression surgery between 2004 and 2010. Health-related quality of life (HRQOL) outcomes were measured using the short form 36 physical component summary (PCS) and the neck disability index (NDI), administered both pre- and postoperatively. Patient comorbidity was evaluated by the CCI and SCQ. The CCI was calculated by the medical record review, whereas the SCQ was obtained from patients’ self-reports. The correlations between HRQOL outcomes and comorbidity indices were investigated. Thereafter, multiple liner regression analyses were performed to assess the performance of these comorbidity indices for predicting postoperative HRQOL. Results. The SCQ significantly correlated with both pre- and postoperative PCS scores and both pre- and postoperative NDI scores. The CCI did not correlate significantly with any outcome measure. On regression analysis, the CCI was a poor predictor of postoperative HRQOL, demonstrating only 0.2% of variance in the PCS score (P = 0.25) and only 0.4% of variance in the NDI score (P = 0.59). In comparison, the SCQ was a significant predictor of postoperative HRQOL, demonstrating 4.0% of variance in PCS score (P = 0.011) and 10.2% of variance in NDI score (P = 0.0001). Conclusion. The SCQ, but not the CCI, was a robust predictor of postoperative HRQOL. Our study suggests that the SCQ score is a more appropriate adjustment for HRQOL outcomes following cervical decompression surgery. Level of Evidence: 3

Spondylodiscitis concurrent with infectious aortic aneurysm caused by Candida tropicalis: a case report

We report a case of spondylodiscitis concurrent with infectious aortic aneurysm caused by Candida tropicalis in a 79-year-old immunocompromised man. The patient underwent percutaneous drainage of the abscess and endoluminal exclusion of the aneurysm using a bifurcated stent graft. Micafungin was administered intravenously for 8 weeks, followed by a prolonged course of oral fluconazole. At the one-year follow-up, no recurrence was noted, and the patient could walk with a cane without low back pain.

Concurrent spinal schwannoma and meningioma mimicking a single cervical dumbbell-shaped tumor: case report.

Dumbbell-shaped tumors consisting of 2 different tumors are extremely rare. Herein, the authors present a case of concurrent spinal schwannoma and meningioma mimicking a single cervical dumbbell-shaped tumor. A 64-year-old man presented with a 5-year history of gradually exacerbating left occipital pain without clinical evidence of neurofibromatosis. Magnetic resonance imaging showed an extradural tumor along the left C-2 nerve root with a small intradural component. The tumor was approached via a C-1 hemilaminectomy. The intradural tumor was resected together with the extradural tumor after opening the dura mater. The intradural tumor was attached to the dura mater around the exit point of the C-2 nerve root. Intraoperative biopsy revealed that the extradural tumor was a schwannoma and that the intradural tumor was a meningioma. The dura mater adjacent to the tumor was then coagulated and resected. Postoperative pathological examination confirmed the same diagnoses with no evidence of continuity between the intra- and extradural components. The patients postoperative clinical course was uneventful. Clinicians should be aware that cervical dumbbell-shaped tumors can consist of 2 different tumors.

In-hospital complication rate following microendoscopic versus open lumbar laminectomy: a propensity score-matched analysis

BACKGROUND CONTEXT The incidence of postoperative complications after microendoscopic laminectomy (MEL) has not been compared with that after open laminectomy in a large study, so it is not clear whether MEL is a safer procedure. PURPOSE The objective of this study was to compare postoperative morbidity and mortality following lumbar laminectomy between patients treated with MEL and with open laminectomy. STUDY DESIGN This is a retrospective cohort study with propensity score-matched analysis. PATIENT SAMPLE Data of patients who underwent elective spinal surgery between July 2010 and March 2013 were extracted from the Diagnosis Procedure Combination database, a nationwide inpatient database in Japan. OUTCOME MEASURES Clinical outcomes included length of hospital stay, occurrence of major complications (cardiac events, respiratory complications, pulmonary embolism, stroke, and acute renal failure), surgical site infection (SSI), postoperative delirium, and in-hospital death. MATERIALS AND METHODS Propensity score matching was performed to adjust for measured confounding factors, including patient age, sex, Charlson Comorbidity Index, body mass index, smoking status, blood transfusion, duration of anesthesia, number of operated disc levels, and type of hospital and hospital volumes. The clinical outcomes of one-to-one propensity-matched pairs of the MEL and the open laminectomy groups were compared. RESULTS Of 23,317 patients identified in the database, 1,536 underwent MEL (6.6%). By one-to-one propensity score matching, 1,536 pairs were selected. The distributions of patient backgrounds were closely balanced between the MEL and the open laminectomy groups. An analysis of 1,536 pairs revealed that there was a significantly lower incidence of major postoperative complications in those who underwent MEL (1.0% vs. 2.8% for open laminectomy, risk difference 1.8%, 95% confidence interval [CI] 0.9%-2.9%), SSI (0.5% vs. 1.6% for open laminectomy, risk difference 1.1%, 95% CI 0.4%-1.9%), and postoperative delirium (1.1% vs. 2.3% for open laminectomy, risk difference1.2%, 95% CI 0.3%-2.1%). The length of hospital stay was significantly shorter in those treated with MEL (12 days vs. 16 days for open laminectomy, p<.001). There was no significant difference in in-hospital mortality between the groups. CONCLUSIONS Patients who underwent MEL were significantly less likely to experience major postoperative complications and were less likely to develop SSI and postoperative delirium than those who underwent open laminectomy.

Mental State Can Influence the Degree of Postoperative Axial Neck Pain Following Cervical Laminoplasty

Study design: A retrospective cohort study. Objective: To investigate factors influencing the incidence of moderate to severe postoperative axial neck pain following cervical laminoplasty. Methods: We reviewed 125 patients with cervical myelopathy who underwent double-door laminoplasty. The primary outcomes were the Numerical Rating Scale score (NRS score, 0-10) for neck pain, the Short Form 36 (SF-36) Health Survey score (Physical and Mental Component Summary scores [PCS and MCS, respectively]), and satisfaction. Imaging parameters on plain radiographs and magnetic resonance imaging were also evaluated. Patients with moderate to severe postoperative neck pain (NRS ≥ 5) were compared with those with no or mild neck pain (NRS ≤ 4). Results: One hundred and three patients (82%) with complete data were eligible for inclusion. There were 67 men and 36 women, with a mean age of 65 years (32-89 years). Twenty-five patients (23%) had moderate to severe postoperative axial pain (NRS ≥ 5) and were compared with the other 78 patients (NRS ≤ 4), which revealed several predictive factors, including female sex, the presence of preoperative neck pain, low postoperative PCS, low preoperative and postoperative MCS, and satisfaction with the treatment. Multivariable logistic regression analysis revealed that the postoperative MCS (P = .002) was a risk factor for postoperative neck pain, although the preoperative MCS did not reach statistical significance (P = .06). Conclusions: Patients with a low mental state, possibly before surgery, are at a high risk for postoperative axial neck pain. None of the imaging parameters were statistically different.