Does Central Sensitization Influence Outcomes of Lumbar Discectomy Surgery in Patients With Lumbar Disc Herniation? A Multicenter Prospective Study.

STUDY DESIGN: Multicenter prospective study. OBJECTIVE: Patients with central sensitization (CS) are reported to be at high risk of poor outcomes after spinal surgery. However, the influence of CS on surgical outcomes for lumbar disc herniation (LDH) remains unknown. This study aimed to examine the association between preoperative CS and surgical outcomes in LDH patients. METHODS: A total of 100 consecutive patients with LDH (mean age 51.2) who underwent lumbar surgery were included in this study. The extent of CS was evaluated using the central sensitization inventory (CSI), a screening tool for CS-related symptoms. The patients completed the following CSI and clinical outcome assessments (COAs) preoperatively and 12 months postoperatively: the Japanese Orthopaedic Association (JOA) score for back pain, JOA back pain evaluation questionnaire (JOABPEQ), and Oswestry Disability Index (ODI). The association between preoperative CSI scores, and preoperative and postoperative COAs was analyzed, and the postoperative changes were statistically evaluated. RESULTS: The preoperative CSI score significantly decreased 12 months postoperatively. Preoperative CSI scores showed a significant correlation with most COAs; however, a significant correlation was only identified in the social function and mental health domains of JOABPEC postoperatively. Higher preoperative CSI showed worse preoperative COAs; however, all COAs significantly improved regardless of CSI severity. There were no significant differences in any COAs among the CSI severity groups 12 months postoperatively. CONCLUSIONS: The results of this study showed that lumbar surgeries significantly improved the COAs regardless of preoperative severity of CS in patients with LDH.

Central sensitization as a predictive factor for the surgical outcome in patients with lumbar spinal stenosis: a multicenter prospective study.

PURPOSE: The impact of central sensitization (CS) on neurological symptoms and surgical outcomes in patients with lumbar spinal stenosis (LSS) remains unknown. This study aimed to investigate the influence of preoperative CS on the surgical outcomes of patients with LSS. METHODS: A total of 197 consecutive patients with LSS (mean age 69.3) who underwent posterior decompression surgery with or without fusion were included in this study. The participants completed the CS inventory (CSI) scores and the following clinical outcome assessments (COAs) preoperatively and 12 months postoperatively: the Japanese Orthopaedic Association (JOA) score for back pain, JOA back pain evaluation questionnaire, and Oswestry Disability Index (ODI). The association between preoperative CSI scores and preoperative and postoperative COAs was analyzed, and postoperative changes were statistically evaluated. RESULTS: The preoperative CSI score significantly decreased at 12 months postoperatively and was significantly correlated with all COAs preoperatively and 12 months postoperatively. Higher preoperative CSI showed worse postoperative COAs and inferior postoperative improvement rates in the JOA score, VAS score for neurological symptoms, and ODI. Multiple regression analysis demonstrated that preoperative CSI was significantly associated with postoperative low back pain (LBP), mental health, quality of life (QOL), and neurological symptoms at 12 months postoperatively. CONCLUSIONS: Preoperative CS evaluated by CSI had a significantly worse impact on surgical outcomes, including neurological symptoms, disability, and QOL, especially related to LBP and psychological factors. CSI can be used clinically as a patient-reported measure for predicting postoperative outcomes in patients with LSS.

Evaluation of Central Sensitization Inventory in Patients Undergoing Elective Spine Surgery in a Multicenter Study.

STUDY DESIGN: This study is a retrospective review. OBJECTIVE: Central sensitization (CS) is a neurological phenomenon that involves hypersensitivity of the central nervous system. The central sensitization inventory (CSI) was developed as a screening tool to assess CS-related symptoms. The purpose of this study was to evaluate the association of preoperative CSI scores with patient-reported outcome measures (PROMs) including neurological symptoms for patients who underwent spine surgeries in a multicenter study. METHODS: A consecutive 673 patients who underwent spine surgery at 8 different institutions were included in this study. Preoperative CSI scores were assessed for all subjects. The participants completed the following PROMs: the Oswestry Disability Index (ODI), the Japanese Orthopaedic Association (JOA) back pain evaluation questionnaire (JOABPEQ) for lumbar spinal diseases, and the JOA cervical myelopathy evaluation questionnaire (JOACMEQ) for cervical spinal diseases. The association of CSI scores with PROMs was statistically evaluated. RESULTS: The average CSI score for the total subjects was 23.6 ± 13.5. The subjects with CS-related symptoms (CSI ≥ 40) were 13.2% (n = 89). The CSI score showed a significant and weak-to-moderate correlation with the PROMs including neurological symptoms that included all the domains of the JOACMEQ for cervical spinal diseases, and JOABPEQ and ODI for lumbar spinal diseases. Among these, psychological factors had the most influence on the correlation with CSI score. CONCLUSION: Central sensitization evaluated by the CSI is related to neurological symptoms and health-related quality of life in patients undergoing elective spine surgery.

Influence of Central Sensitization on Surgical Outcomes of Patients With Degenerative Cervical Myelopathy After Posterior Decompression Surgery: A Multicenter Prospective Study.

STUDY DESIGN: Multicenter prospective study. OBJECTIVE: The influence of central sensitization (CS) on neurological symptoms and surgical outcomes in patients with degenerative cervical myelopathy (DCM) remains unknown. This study aimed to investigate the effects of preoperative CS on surgical outcomes of patients with DCM following posterior decompression surgery. METHODS: 77 consecutive patients with DCM (mean age 67.1) who received posterior decompression surgery were included in this study. The participants completed CS inventory (CSI) scores and the following patient-reported outcome measures (PROMs) preoperatively and 12 months postoperatively: the Japanese Orthopaedic Association (JOA) score for cervical myelopathy and JOA cervical myelopathy evaluation questionnaire (JOACMEQ) for cervical spinal diseases. The association of preoperative CSI scores with preoperative and postoperative PROMs was analyzed, and their changes were statistically evaluated. RESULTS: The preoperative CSI score was significantly decreased at 12 months postoperatively, and it was significantly associated with the JOA score and JOACMEQ preoperatively and at 12 months postoperatively. However, no significant association was observed between preoperative CSI and the postoperative change of any PROMs at 12 months. The posterior decompression surgery significantly improved the JOA scores and 'lower extremity function' and 'quality of life (QOL)' domains of the JOACMEQ, independent of the severity of preoperative CSI score. Multiple regression analysis demonstrated that preoperative CSI was significantly associated with the 'QOL' domain of JOACMEQ and original JOA score at 12 months postoperatively. CONCLUSION: The CSI score can be an auxiliary indicator of surgical outcomes of patients with DCM following posterior decompression surgery.

Biomechanical Problems Related to the Pedicle Screw System.

AIM: To assess biomechanical problems related to pedicle screw (PS) systems. MATERIAL AND METHODS: Functional spinal units (L3-4) of deer were evaluated using a 6-axis material testing machine. For the specimen models, we prepared an intact model, a damaged model, a PS model, and a crosslink model. We checked the range of motion (ROM) during bending and rotation tests. Eight directions were measured in the bending test: anterior, right-anterior, right, right-posterior, posterior, left-posterior, left, and left-anterior, and 2 directions were measured in the rotation test (right and left). RESULTS: ROMs of the PS model were smaller than those of the intact model in all directions. However, ROMs of the PS model in the rotation test were smaller than those of the damaged model and larger than those of the intact model. The stability of the crosslink model was better than that of the PS model during the bending test, but ROMs of the crosslink model were larger than those of the intact model during the rotation test. CONCLUSION: Excessive bending rigidity and rotational instability are the biomechanical problems related to PS systems. Based on these results, we speculate that one of the most significant causes of adjacent segment disease is excessive bending rigidity and one of the most important causes of instrumentation failure is rotational instability.

A survey of workplace violence against physicians in the hospitals, Myanmar.

OBJECTIVE: Workplace violence in hospitals is recently becoming a major global concern in many countries. However, in Myanmar, we have felt that patients and their families have rarely made unreasonable complaints in hospitals, and then, the purpose of this study is to report the current state of workplace violence in hospitals in Myanmar. Participants are 196 physicians (108 males and 88 females) in hospitals in Myanmar. RESULTS: A descriptive survey was conducted in regard to verbal abuse and physical violence from patients or the people concerned. At the results of this study, the percentages of physicians who have encountered verbal abuse and those who have encountered physical violence are markedly low (8.7 and 1.0%, respectively). The present study is the first to report the frequencies of verbal abuse and physical violence against physicians in a least developed country, and the results of the present study are important in terms of discussing workplace violence in hospitals.

RETRACTED: Three-Minutes Sitting Test for evaluating lumbar foraminal stenosis: A preliminary report.

This article has been retracted.

Biomechanical Stability of a Cross-Rod Connection with a Pedicle Screw System.

BACKGROUND Surgery with pedicle screw instrumentation does not provide sufficient torsional stability. This leads to pseudoarthrosis, loosening of the pedicle screws, and, ultimately, implant failure. MATERIAL AND METHODS Functional spinal units from 18 deer were evaluated using a 6-axis material testing machine. As specimen models, we prepared an intact model, a damaged model, a cross-rod model, and a cross-link model. We measured the range of motion (ROM) during bending and rotation tests. RESULTS The range of motions of cross-rod model were almost equal to those of cross-link model during the bending test. In the rotation test, the average ranges of motion of the intact, cross-rod, and cross-link models were 2.9°, 3.1°, and 3.9° during right rotation and 2.9°, 3.1°, and 4.1° during left rotation, respectively. The range of motions of the cross-rod model were significantly smaller than those of the cross-link model during the rotation test. The range of motions of the intact model were significantly smaller than those of the cross-link model during the rotation test, but there were no statistically significant differences between the range of motions of intact model and cross-rod model during the rotation test. CONCLUSIONS The stability of spinal fixation such as cross-rod model is equal to the fixation using the pedicle screw system during bending tests and equal to that of the intact spine during rotation tests.

Trajectory of instantaneous axis of rotation in fixed lumbar spine with instrumentation.

BACKGROUND: Several studies showed instantaneous axis of rotation (IAR) in the intact spine. However, there has been no report on the trajectory of the IAR of a damaged spine or that of a fixed spine with instrumentation. It is the aim of this study to investigate the trajectory of the IAR of the lumbar spine using the vertebra of deer. METHODS: Functional spinal units (L5-6) from five deer were evaluated with six-axis material testing machine. As specimen models, we prepared a normal model, a damaged model, and a pedicle screw (PS) model. We measured the IAR during bending in the coronal and sagittal planes and axial rotation. In the bending test, four directions were measured: anterior, posterior, right, and left. In the rotation test, two directions were measured: right and left. RESULTS: The IAR of the normal model during bending moved in the bending direction. The IAR of the damaged model during bending moved in the bending direction, but the magnitude of displacement was bigger compared to that of the normal model. In the PS model, the IAR during bending test hardly moved. During rotation test, the IAR of the normal model and PS model located in the spinal canal, but the IAR of the damaged model located in the posterior part of the vertebral body. CONCLUSIONS: In this study, the IAR of damaged model was scattering and that of PS model was concentrating. This suggests that higher mechanical load applied to the dura tube and nerve roots in the damaged model and less mechanical load applied to that in the PS model.

Tumoral calcinosis in the cervical spine: a case report and review of the literature.

BACKGROUND: Tumoral calcinosis is rarely located in spine. A 55-year-old Japanese woman with cervical tumoral calcinosis is presented, along with a review of the literature relating to tumoral calcinosis in the spine. We discussed the etiology, diagnosis, and management of this condition. CASE PRESENTATION: We report a case of a patient with cervical tumoral calcinosis with end-stage renal disease. A computed tomography scan showed a lobulated, calcified mass around the right facet joint at the fourth-fifth cervical spine and calcifications were also observed in the right intervertebral foramens at fourth-fifth cervical spine and fifth-sixth cervical spine levels and the anterior wall of the spinal canal. By performing a cervical decompression and stabilization, the patient recovered from her neurological symptoms. CONCLUSIONS: Although tumoral calcinosis is rarely located in the spine, it should be considered in the differential diagnosis of spinal lesions. If a calcified mass causes acute neurological symptoms, resection of the mass is still the most important treatment.

Characteristics of Patients with High Lie Scores in a Personality Test.

BACKGROUND: It is reported that persons with high Lie score (L score) of a personality test are aggressively self-confident and are also related to depression or schizophrenia In this study, we examined the characteristics of patients with high L scores on the Maudsley Personality Inventory (MPI) and examined the significance of the L score. MATERIALS AND METHODS: We collected the data of 10789 subjects and examined the relationship between L score or the number of characteristic biased persons and the parameters of age, sex, education level, occupation, and degree of pain. Furthermore, we examined the changes in extraversion-introversion (E score), neuroticism (N score), and L scores at approximately 1 year after surgery in 1711 patients who underwent surgery at our university hospital or affiliated hospitals. RESULTS: L score was significantly higher among persons with a high degree of pain, and ratio of the characteristic biased persons in L score was significantly high among persons in their 40s to 60s, healthcare professionals and those with a high degree of pain. Moreover, L score scarcely changed between before and after surgery when compared with E score and N score. CONCLUSION: L score is not greatly influenced by an individual's state of mind or situation at different times, and may indicate the personality traits proper to the person. It is shown that L score may indicate the personality trait characteristics of persons who want to make themselves look good in the eyes of other.

Intradiscal Injection of Autologous Platelet-Rich Plasma Releasate to Treat Discogenic Low Back Pain: A Preliminary Clinical Trial.

STUDY DESIGN: Preliminary clinical trial. PURPOSE: To determine the safety and initial efficacy of intradiscal injection of autologous platelet-rich plasma (PRP) releasate in patients with discogenic low back pain. OVERVIEW OF LITERATURE: PRP, which is comprised of autologous growth factors and cytokines, has been widely used in the clinical setting for tissue regeneration and repair. PRP has been shown in vitro and in vivo to potentially stimulate intervertebral disc matrix metabolism. METHODS: Inclusion criteria for this study included chronic low back pain without leg pain for more than 3 months; one or more lumbar discs (L3/L4 to L5/S1) with evidence of degeneration, as indicated via magnetic resonance imaging (MRI); and at least one symptomatic disc, confirmed using standardized provocative discography. PRP releasate, isolated from clotted PRP, was injected into the center of the nucleus pulposus. Outcome measures included the use of a visual analog scale (VAS) and the Roland-Morris Disability Questionnaire (RDQ), as well as X-ray and MRI (T2-quantification). RESULTS: Data were analyzed from 14 patients (8 men and 6 women; mean age, 33.8 years). The average follow-up period was 10 months. Following treatment, no patient experienced adverse events or significant narrowing of disc height. The mean pain scores before treatment (VAS, 7.5±1.3; RDQ, 12.6±4.1) were significantly decreased at one month, and this was generally sustained throughout the observation period (6 months after treatment: VAS, 3.2±2.4, RDQ; 3.6±4.5 and 12 months: VAS, 2.9±2.8; RDQ, 2.8±3.9; p<0.01, respectively). The mean T2 values did not significantly change after treatment. CONCLUSIONS: We demonstrated that intradiscal injection of autologous PRP releasate in patients with low back pain was safe, with no adverse events observed during follow-up. Future randomized controlled clinical studies should be performed to systematically evaluate the effects of this therapy.

Do the Position and Orientation of the Crosslink Influence the Stiffness of Spinal Instrumentation?

STUDY DESIGN: Biomechanical study of double-level pedicle screw constructs with or without crosslinks (CL) in an unstable model. OBJECTIVES: The purpose of this study is to investigate the optimal position and orientation of the CL. SUMMARY OF BACKGROUND DATA: Several reports have described biomechanical research on such CL, but no definite consensus has been reached regarding the effects. Very few studies have examined the position and orientation of the CL. The question of where and how the CL should be clinically set remains unanswered. METHODS: Ten cadaveric lumbar spines (L3-L5) of boars were used and 7 models were prepared by the sequential damage and spinal instrumentation of each specimen. Bending stiffness was measured in flexion, extension, lateral bending, and axial rotation for each model using 6-axis material tester under torque of 0 to ±3 N m. Results for each configuration were compared using analysis of variance and the Turkey-Kramer test. RESULTS: In flexion, extension, and lateral bending, 7 models showed similar stiffness with no significant differences. In axial rotation, stiffness increased significantly (P<0.05) in the cephalic, central, caudal, and oblique CL models in comparison with that of the no CL model, and stiffness of the horizontal 2 CL and oblique 2 CL models was significantly higher than that of cephalic, central, caudal, and oblique CL models (P<0.05). However, no significant differences in stiffness were seen between cephalic, central, and caudal CL models, between the central and oblique CL models, or between the horizontal and oblique 2 CL models. CONCLUSIONS: Concomitant use of CLs significantly increased axial rotational stiffness, even though stiffness in flexion, extension, and lateral bending was not increased. In addition, stiffness in axial rotation significantly improved with the use of 2 CLs instead of a single CL, and stiffness was unchanged by position and orientation of CL.

Psychological effects of meditation at a Buddhist monastery in Myanmar.

BACKGROUND: Meditation is widely used as a therapeutic measure because it can effectively reduce stress, pain, and improve the mental health, but there are many unclear points about the psychological effects of meditation. AIMS: The purpose of this study is to verify the psychological effects of meditation. METHOD: The short version of Profile of Mood States (POMS-SF) and the Acceptance and Action Questionnaire-II (AAQ-II) were conducted to compare 97 Myanmar people practicing Vipassana contemplation training with 81 Myanmar nurses who did not have any experience with meditation. RESULTS: The results of our study revealed that meditation mitigated depressive mood, anger, hostility, and fatigue and increased vigor. The enhancement of psychological flexibility occurred only after practicing meditation for more than a year. CONCLUSIONS: It can be considered that meditation mitigates anger, hostility and fatigue and increases vigor at a relatively early stage after starting meditation practice, and if meditation practice is continued for more than a year, enhancement of psychological flexibility can also be expected.

The Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ): A validation of the reliability of the Thai version.

BACKGROUND: The Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) was developed by the Japanese Orthopedic Association (JOA) for assessment of lower back pain and lumbar spinal disease. We aimed to translate the JOABPEQ into Thai and test its reliability and validity in the Thai context. METHODS: The original JOABPEQ was translated into Thai in accordance with international recommendations. Then 180 lumbar spinal disease patients (mean age 58.58 ± 11.97, 68.3% female) were asked to complete the Thai version of the JOABPEQ twice at 2-week intervals. Test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was compared with the Thai version of the modified SF-36, and tested using the Spearman's rank correlation coefficient. RESULTS: The Thai JOABPEQ showed satisfactory test-retest reliability in all parameters (Intra-class Correlation Coefficient 0.761-0.862). The variables low back pain, walking ability, social life function, and mental health had satisfactory internal consistency (the respective Cronbach's α was 0.798, 0.721, 0.707, and 0.795). Only the lumbar function parameter showed moderate reliability (Cronbach's α = 0.654). All of the variables in the Thai JOABPEQ had a statistically positive correlation with the correspondent Thai SF-36 subscales (Spearman's rank correlation p value < 0.05). CONCLUSION: The Thai version of JOABPEQ had satisfactory internal consistency, test-retest reliability, and construct validity; it can be used as a reliable tool for assessing quality of life for lumbar spinal disease patients in Thailand.

Relief of Lower Back and Leg Pain after Myelography.

INTRODUCTION: It is well-known that many patients will have adverse reactions such as headache and nausea after undergoing myelography, but we have often seen cases where symptoms such as lower back pain and leg pain were alleviated following myelography. To the best of our knowledge, such clinical cases of post-myelographic alleviation have not been reported. MATERIALS AND METHODS: A total of 325 patients with a degenerative lumbar spinal disorder who underwent myelography were prospectively investigated at four hospitals from April 2012 to March 2014 to survey the post-myelographic alleviation of lower back and leg pain prospectively. The severities of lower back pain, leg pain and numbness of the lower extremities were evaluated and intermittent claudication distance was measured before myelography. The magnetic resonance imaging (MRI) findings and myelographic findings were also evaluated for the patients that their symptoms were improved. RESULTS: Thirty-five of 325 cases (10.8%) of these patients had their symptoms alleviated after undergoing myelography; 26 cases of lower back pain, two cases of leg pain, two cases of numbness of the lower extremity, and five cases of intermittent claudication. CONCLUSION: In the patients of a degenerative lumbar spinal disorder, about 10% cases with lower back pain or intermittent claudication had post-myelographic alleviation. Intradural injection therapy might be a therapeutic method to alleviate these symptoms.

Biomechanical study of rotational micromovement of the pedicle screw.

BACKGROUND: In regard to the fixation using a pedicle screw (PS) and rod system, the mechanism from the onset of the clear zone up to the development of loosening of the pedicle screw is not completely clarified. The purpose of this study is to determine the cause of the pedicle screw loosening by performing a biomechanical study with three-dimensional movie analysis. METHODS: Ten PS fixation model of the lumbar spines (L3-4) of boar cadavers were used. The rotational angles of the L3 and L4 vertebral body and the screw at the time of applying a ±5 Nm load in the left anterior and right posterior flexion directions respectively were calculated based on those at the time of applying no load. The absolute value of the difference in the rotational angles between each vertebral body with left anterior flexion and right posterior flexion and the inserted screws was defined as rotational micromovement. RESULTS: In both the left anterior and right posterior flexion directions, there were significant differences (p < 0.05) in the rotational angles between the screw and the vertebral body for both the L3 and L4 vertebral bodies. CONCLUSION: Our biomechanical results showed that rotational micromovement occurred between the PS and the vertebral body, and repeated rotational micromovement might cause loosening of the screw or pullout of PS fixation.

Validation of the reliability of the Thai version of the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ).

BACKGROUND: The Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) was developed to resolve problems associated with the original evaluation of cervical myelopathic patients. The aim of this study was to translate the JOACMEQ into Thai as per international recommendations, and to test its reliability and validity in the Thai context METHODS: The JOACMEQ was translated into Thai, using international guidelines. Cervical myelopathy patients (n = 70; 31 males) were asked to complete the Thai version JOACMEQ twice (4 weeks apart). Test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was compared with the Thai version modified SF-36; using the Spearman's rank correlation coefficient. RESULTS: The Thai JOACMEQ produced good reliability (i.e., the ICC was >0.9 in 2 parameters and >0.8 in one). Overall the Cronbach's α for the 24 questions showed very high internal consistency (Cronbach's α > 0.8) and almost all Cronbach's α showed satisfactory internal consistency except for bladder function. The Spearman's rank correlation for all the JOACMEQ parameters had a positive correlation with all Thai SF 36 subscales, especially the quality of life parameter, which showed a strong correlation with all SF-36 subscales. CONCLUSION: The Thai version of the JOACMEQ had satisfactory internal consistency and test-retest reliability: it also had good construct validity. It can therefore be used as a reliable tool for assessing quality of life for cervical myelopathy patients in Thailand.

A Case of Lumbosacral Arachnoiditis Ossificans.

The patient was a 13-year-old boy who complained of pain in both buttocks. Plain and reconstructive computed tomography (CT) images showed an ossified lesion within the dura mater at the L5-S2 levels, and arachnoiditis ossificans in the lumbosacral area was suspected. In the operative findings obtained after cutting the dura, a bone fragment 4.5 × 0.5 × 0.5 cm in size was observed in the center of the strongly adhesive nerve bundle of the cauda equina, which was removed en bloc. The postoperative clinical course of the patient was excellent. The case, along with a review of literature is presented.