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.

Cervical schwannoma in the early stage of pregnancy: a case report.

BACKGROUND: Although spinal schwannomas generally grow very slowly, it has been reported that these clinical growths and their associated neurological symptoms accelerate during pregnancy. Because these cases are rare, surgical intervention for this tumor during pregnancy poses a significant challenge. The change of pregnancy-related hormones, such as estrogen and progesterone, is considered to have an effect on the clinical symptoms of spinal tumors. Expressions of the receptors for estrogen and progesterone in orbital and vestibular schwannomas have been reported; however, those expressions in spinal schwannomas have not been examined. CASE PRESENTATION: A 36-year-old woman at 8 weeks' gestation suffered from developing neck pain and neurological symptoms in the right upper extremity. Magnetic resonance imaging (MRI) confirmed the presence of a cervical intradural extramedullary tumor. Under general anesthesia, using intraoperative neurophysiological monitoring of motor-evoked potentials (MEPs), spinal tumor resection following a hemi-laminoplasty was performed in a prone position at 12 weeks gestation. The pathological diagnosis following surgery was spinal schwannoma. Her neurological symptoms were significantly improved after surgery and she delivered a healthy baby in her 40th week of pregnancy. At a 12-month follow-up, no abnormalities were observed during medical examinations of both mother and child. An immunohistochemical study identified the expression of estrogen receptors, but not progesterone receptors, in the spinal schwannoma. CONCLUSIONS: A cervical spinal schwannoma was successfully removed under general anesthesia at 12 weeks gestation by coordination between orthopaedic, obstetric and anesthesia teams. For the first time, an immunohistochemical analysis showed that the expression of estrogen receptors was identified in spinal schwannoma cells, suggesting the possibility that these hormone receptors in spinal schwannoma might contribute to the worsening of neurological symptoms during pregnancy.

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.

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.

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.

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.

Activated protein C stimulates osteoblast proliferation via endothelial protein C receptor.

INTRODUCTION: Bone is continually remodeled by the action of osteoblasts, osteocytes, and osteoclasts. Resting osteoblasts are able to proliferate and differentiate into mature osteoblasts when physiologically required, as after tissue injury. Activated protein C (APC) is a serine protease that functions in anticoagulation, anti-inflammation, anti-apoptosis, cell proliferation, and wound repair. In this study, we examined the effect of APC on osteoblast proliferation and differentiation. MATERIALS AND METHODS: We examined the presence of protein C in human fracture hematoma by immunohistochemical staining. We then evaluated the effect of APC, diisopropyl fluorophosphate-inactivated APC (DIP-APC) or protein C zymogen on normal human osteoblast (NHOst) proliferation using tetrazolium salt assay in the presence or absence of aprotinin, hirudin, protein C, antibody against protein C, endothelial protein C receptor (EPCR) or protease-activated receptor (PAR)-1. Finally, activation of p44/42 MAP kinase was evaluated by Western blot analysis. RESULTS: Both APC and DIP-APC increased osteoblast proliferation in a dose-dependent manner, while protein C did not. The APC-induced increased proliferation of osteoblast was not affected by aprotinin, hirudin, and anti-protein C antibody which inhibits the protease activity of APC. Treatment with protein C or anti-EPCR antibody which inhibits APC binding to EPCR inhibited APC-mediated osteoblast proliferation, while treatment with anti-PAR-1 antibody did not. APC promoted the phosphorylation of p44/42 MAP kinase within osteoblasts; this effect was inhibited by the anti-EPCR antibody. CONCLUSIONS: APC stimulates osteoblast proliferation by activating p44/42 MAP kinase through a mechanism that requires EPCR but not PAR-1 or the proteolytic activity of APC. APC generated at fracture sites may contribute to fracture healing by promoting osteoblast proliferation.