古矢 丈雄

PURPOSE: Pain from osteoarthritis (OA) is generally classified as nociceptive (inflammatory). Animal models of knee OA have shown that sensory nerve fibers innervating the knee are significantly damaged with destruction of subchondral bone junction, and induce neuropathic pain (NP). Our objective was to examine NP in the knees of OA patients using painDETECT (an NP questionnaire) and to evaluate the relationship between NP, pain intensity, and stage of OA. MATERIALS AND METHODS: Ninety-two knee OA patients were evaluated in this study. Pain scores using Visual Analogue Scales (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), painDETECT, duration of symptoms, severity of OA using the Kellgren-Lawrence (KL) system, and amount of joint fluid were evaluated and compared using a Spearman's correlation coefficient by rank test. RESULTS: Our study identified at least 5.4% of our knee OA patients as likely to have NP and 15.2% as possibly having NP. The painDETECT score was significantly correlated with the VAS and WOMAC pain severity. Compared with the painDETECT score, there was a tendency for positive correlation with the KL grade, and tendency for negative correlation with the existence and amount of joint fluid, but these correlations were not significant. CONCLUSION: PainDETECT scores classified 5.4% of pain from knee OA as NP. NP tended to be seen in patients with less joint fluid and increased KL grade, both of which corresponded to late stages of OA. It is important to consider the existence of NP in the treatment of knee OA pain.

STUDY DESIGN: Case report. OBJECTIVE: Diagnosis of symptomatic extra-foraminal lumbosacral stenosis using diffusion tensor imaging (DTI). SUMMARY OF BACKGROUND DATA: Conventional magnetic resonance imaging (MRI) has sometimes proved inadequate for evaluating symptomatic spinal nerve lesions. DTI has been developed to visualize anisotropy of nerve-fiber tracts to evaluate nerve degeneration. We report a case of nerve compression causing a far-out lesion diagnosed using DTI. METHODS: A 68-year-old patient presented with an 8-month history of severe right-sided sciatica. Computed tomography and MRI showed right L5-S1 foraminal stenosis and contact of the L5 transverse process and S1 ala without canal stenosis at the L4-L5 level. We evaluated the fractional anisotropy (FA) of the right L5 spinal nerve and compared it with bilateral L3-S1 spinal nerves to determine the L5 spinal nerve compression site. RESULTS: DTI revealed narrowing of the right L5 spinal nerve between the L5 transverse process and S1 ala. FA was significantly decreased in the right L5 spinal nerve between the L5 transverse process and S1 ala. There was no significant difference in the FA of spinal nerves between the right and left sides at L3, L4, or S1. The right L5 spinal nerve from the central spinal canal to the extra-foraminal lumbosacral lesion was exposed during surgery and found to be severely compressed by the L5 transverse process and S1 ala. Postoperatively, the patient's symptoms disappeared immediately. CONCLUSION: We used DTI to diagnose a symptomatic lesion as an extra-foraminal lumbosacral lesion caused by compression of the L5 spinal nerve at the foramina. Because DTI can quantitatively measure damage to nerve fibers, it may be advantageous for the diagnosis of far-out syndrome.

Based on the neuroprotective effects of granulocyte colony-stimulating factor (G-CSF) on experimental spinal cord injury, we initiated a clinical trial that evaluated the safety and efficacy of neuroprotective therapy using G-CSF for patients with worsening symptoms of compression myelopathy. We obtained informed consent from 15 patients, in whom the Japanese Orthopaedic Association (JOA) score for cervical myelopathy decreased two points or more during a recent 1-month period. G-CSF (5 or 10 mu g/kg/day) was intravenously administered for five consecutive days. We evaluated motor and sensory functions of the patients and the presence of adverse events related to G-CSF therapy. G-CSF administration suppressed the progression of myelopathy in all 15 patients. Neurological improvements in motor and sensory functions were obtained in all patients after the administration, although the degree of improvement differed among the patients. Nine patients in the 10-mu g group (n = 10) underwent surgical treatment at 1 month or later after G-CSF administration. In the 10-mu g group, the mean JOA recovery rates 1 and 6 months after administration were 49.9 +/- A 15.1 and 59.1 +/- A 16.3%, respectively. On the day following the start of G-CSF therapy, the white blood cell count increased to more than 22,700 cells/mm(3). It varied from 12,000 to 50,000 and returned to preadministration levels 3 days after completing G-CSF treatment. No serious adverse events occurred during or after treatment. The results indicate that G-CSF administration at 10 mu g/kg/day is safe for patients with worsening symptoms of compression myelopathy and may be effective for their neurological improvement.

STUDY DESIGN: Prospective trial. OBJECTIVE: To examine the bone union and clinical results after unilateral or bilateral instrumented posterolateral fusion surgery using a local bone graft. SUMMARY OF BACKGROUND DATA: The iliac crest bone graft technique for lumbar posterolateral fusion surgery is widely used; however, donor site problems such as pain and sensory disturbance have been reported. Local bone has been used for bilateral multisegment fusion surgery; however, outcomes have been poor because of insufficient amounts of local bone used. This study evaluated unilateral and bilateral posterolateral fusion at 3 levels using a local bone graft. METHODS: Sixty-two patients diagnosed with degenerated spondylolisthesis at 3 levels were divided into 2 groups. All underwent decompression and bilateral instrumented posterolateral fusion. However, a unilateral local bone graft was used in 32 patients and bilateral local bone graft was used in 30 patients. The amount of bone grafting, proportion of patients with bone union, duration of bone union, visual analog scale score, Japanese Orthopedic Association score, and Oswestry Disability Index were evaluated before and 2 years after surgery. RESULTS: Visual analog scale score, Japanese Orthopedic Association score, and Oswestry Disability Index were not significantly different between the 2 groups before and after surgery (P > 0.05). The amount of local bone graft used for each segment was significantly less in the bilateral group (P < 0.05). The proportion of patients with rates of bone union and instability were 86% and 9%, respectively, in the unilateral group, but significantly poorer at 60% and 34% in the bilateral group. CONCLUSION: If multisegment fusion (3-level fusion) is performed, bilateral local bone grafting results in a poor rate of bone union because of an insufficiency of local bone. Unilateral bone grafting is recommended because better rates of bone union and stability are achieved.

Object. Granulocyte colony-stimulating factor (G-CSF) has neuroprotective effects on the CNS. The authors have previously demonstrated that G-CSF also exerts neuroprotective effects in experimental spinal cord injury (SO) by enhancing migration of bone marrow derived cells into the damaged spinal cord, increasing glial differentiation of bone marrow derived cells, enhancing antiapoptotic effects on both neurons and oligodendrocytes, and by reducing demyelination and expression of inflammatory cytokines. Because the degree of angiogenesis in the subacute phase after SCI correlates with regenerative responses, it is possible that G-CSF&apos;s neuroprotective effects after SCI are due to enhancement of angiogenesis. The aim of this study was to assess the effects of G-CSF on the vascular system after SCI. Methods. A contusive SCI rat model was used and the animals were randomly allocated to either a G-CSF-treated group or a control group. Integrity of the blood spinal cord barrier was evaluated by measuring the degree of edema in the cord and the volume of extravasation. For histological evaluation, cryosections were immunostained with anti-von Willebrand factor and the number of vessels was counted to assess revascularization. Real-time reverse transcriptase polymerase chain reaction was performed to assess expression of angiogenic cytokines, and recovery of motor function was assessed with function tests. Results. In the G-CSF treated rats, the total number of vessels with a diameter &gt; 20 mu m was significantly larger and expression of angiogenic cytokines was significantly higher than those in the control group. The G-CSF treated group showed significantly greater recovery of hindlimb function than the control group. Conclusions. These results suggest that G-CSF exerts neuroprotective effects via promotion of angiogenesis after SCI. (DOI: 10.3171/2011.5.SPINE10421)

BACKGROUND: Surgery for lumbar spondylolisthesis is widely performed. However, there have been no reports comparing posterolateral and anterior interbody fusion prospectively. We compared instrumented posterolateral fusion with anterior interbody fusion for L4 spondylolisthesis in a prospective study. METHODS: Forty-six patients diagnosed with L4 degenerated spondylolisthesis were divided into two groups. Twenty-two consecutive patients underwent non-instrumented anterior interbody fusion using an iliac bone graft (ALIF; L4-L5 level), and 24 consecutive patients underwent instrumented posterolateral fusion with local bone (PLF; L4-L5 level). The rates of bone union, visual analog scale (VAS) score, Japanese Orthopedic Association (JOA) score, Oswestry Disability Index (ODI), surgical invasion, and complications were evaluated before and 2 years after surgery. RESULTS: Age, VAS score, JOA score, and ODI were not significantly different between the two groups before surgery (P > 0.05). Success of bone union between the two groups was not significantly different (P > 0.05). Blood loss during surgery was significantly less; however, periods of bed rest and hospital stay were significantly longer in the ALIF group (P < 0.05). Overall patient satisfaction, and low back and leg pain in both groups were significantly improved after surgery; however, low back pain showed greater improvement in the ALIF group compared with the PLF group (P < 0.05). Complications such as donor site pain (4 patients in the ALIF group) and dural tearing (3 patients in the PLF group) were observed. CONCLUSIONS: If single level fusion for L4 spondylolisthesis is performed, both anterior and posterior methods reduce patients' low back and leg pain. Improvement of low back pain was significantly greater after ALIF; however, periods of hospital stay and of bed rest were significantly longer.

A 60-year-old man presented with thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). His spinal cord was severely impinged anteriorly by a beak-type OPLL and posteriorly by ossification of the ligamentum flavum at T4/5. He underwent surgical posterior decompression with instrumented fusion (PDF). Immediately after surgery, he developed a Brown-Sequard-type paralysis, which spontaneously resolved without requiring the addition of OPLL extirpation. This example highlights that the risk of postoperative neurological deterioration cannot be eliminated even when PDF is selected as the surgical procedure for thoracic OPLL, especially in instances in which the spinal cord is severely compressed. (C) 2010 Elsevier Ltd. All rights reserved.

We evaluated the feasibility and reliability of open source Digital Imaging and COmmunication in Medicine (DICOM) imaging software, OsiriX (Antoine Rosset, 2003-2009), in spine surgery. CT data were used and processed with OsiriX and with commercial software for comparison. Images were reconstructed and compared in volume rendering (VR) and multi-planar reconstruction (MPR) mode. When all images were compared, the three-dimensional (3D) reconstructed images from both software packages showed considerable consistency in VR mode. Measurements in MPR mode also showed similar values with no statistically significant difference. These results demonstrate that OsiriX has approximately equivalent values to commercial software and provides reliable preoperative 3D information for the surgical field. In addition, any clinician, can obtain information using OsiriX at any time. Thus, OsiriX is a helpful tool in preoperative planning for spine surgery. (C) 2009 Elsevier Ltd. All rights reserved.

We evaluated the clinical results of posterior decompression with instrumented fusion (PDF) for thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). A total of 24 patients underwent PDF, and their surgical outcomes were evaluated by the Japanese Orthopaedic Association (JOA) scores (0-11 points) and by recovery rates calculated at 3, 6, 9 and 12 months after surgery and at a mean final follow-up of 4 years and 5 months. The mean JOA score before surgery was 3.7 points. Although transient paralysis occurred immediately after surgery in one patient (3.8%), all patients showed neurological recovery at the final follow-up with a mean JOA score of 8.0 points and a mean recovery rate of 58.1%. The mean recovery rate at 3, 6, 9 and 12 months after surgery was 36.7, 48.8, 54.0 and 56.8%, respectively. The median time point that the JOA score reached its peak value was 9 months after surgery. No patient chose additional anterior decompression surgery via thoracotomy. The present findings demonstrate that despite persistent anterior impingement of the spinal cord by residual OPLL, PDF can result in considerable neurological recovery with a low risk of postoperative paralysis. Since neurological recovery progresses slowly after PDF, we suggest that additional anterior decompression surgery is not desirable during the early stage of recovery.

Study Design. Case report.Objective. To describe the usefulness of simulated surgery for evaluation of a patient with neurofibromatosis type-1 (NF-1) who had severe cervicothoracic kyphoscoliosis and an anomalous vertebral artery (VA).Summary of Background Data. Several surgical procedures have been used in the treatment of cervicothoracic kyphoscoliosis associated with myelopathy in patients with NF-1. However, to our knowledge, there has been no report that describes a surgical procedure for NF-1 patients with anomalous VA at the cervical spine.Methods. A 45-year-old man with NF-1 developed cervical myelopathy. Preoperative examinations revealed severe cervicothoracic kyphoscoliosis, dystrophic changes of the cervical vertebrae, and the anomalous course of a VA and VA aneurysms. To assist in the preoperative planning and intraoperative navigation, we created 3-dimensional (3D) full-scale models of the patient's spine. Using a model, we performed a simulation of the planned surgery for spinal cord decompression with spinal fusion through both anterior and posterior approaches.Results. Through the simulation, we could evaluate the risk of VA injury at the process of corpectomy, and altered the surgical procedure for the spinal cord decompression with spinal fusion from a posterior approach and a bone graft alone from an anterior approach. We accomplished the surgery successfully without any neurovascular complications. After surgery, the patient experienced relief from myelopathy.Conclusion. Preoperative surgical simulation using a 3D full-scale model was useful for improving the accuracy and safety of the surgery for cervicothoracic kyphoscoliosis with NF-1.

Study Design. Case report.Objective. To report a surgically treated case of cervical ossification of the posterior longitudinal ligament (OPLL), in which a spinal subarachnoid hematoma (SSAH) developed intraoperatively but was successfully treated.Summary of Background Data. Previous reports have indicated that trauma, lumbar puncture, vascular lesions such as arteriovenous malformation, neoplastic lesions, and coagulopathy can cause SSAH. To the best of our knowledge, there has been no report that describes the occurrence of SSAH during anterior decompression surgery of the cervical spine.Methods. A 52-year-old man with cervical myelopathy caused by OPLL underwent surgery for anterior decompression from C2/3 to C6/7. Immediately after the OPLL floating procedure, cerebrospinal fluid leakage and massive bleeding occurred at right edge of the OPLL at the C3-C4 level. After hemostasis, the dura mater at the C5-C6 levels bulged rapidly and became cyanotic. Intraoperative ultrasonographic images showed a high-intensity mass lesion on the ventral side of the spinal cord, indicating an intrathecal hematoma.Results. We incised the dura, found the hematoma under the intact arachnoid, and removed it. We then found that the bleeding occurred from the radicular artery along the right C4 root. After hemostasis, we performed anterior spine fusion from C2-C7. After surgery, the patient's myelopathy was improved, and no neurologic deficit related to the subarachnoid hematoma was found.Conclusion. This experience suggests that when anterior decompression surgery is performed for cervical OPLL patients, we should consider the possible occurrence of an SSAH. Intraoperative ultrasonography is a useful tool for detecting SSAHs.

We studied 27 patients with cervical ossification of the posterior longitudinal ligament (OPLL) but no clinical symptoms of myelopathy. We investigated the occupation ratio of the spinal canal by OPLL with cervical radiographs, assessed the morphological types of OPLL, and measured the segmental range of motion (ROM) at the level of maximum cord compression on flexion and extension radiographs. Patients were classified as having continuous-type OPLL (17 patients), mixed-type OPLL (seven patients), or segmental-type OPLL (three patients). The segmental ROM was negatively correlated with the OPLL occupation ratio (r = -0.49, p &lt; 0.01). No patient developed myelopathy during the study period. Three patients with massive OPLL did not develop myelopathy and the mobility of their cervical spine was highly suggesting that dynamic factors such as the segmental ROM preferentially contribute to the restricted, development of myelopathy in patients with cervical OPLL. Thus, by controlling the dynamic factors (hypermobility), we might be able to reduce neurological deterioration in patients with cervical OPLL. (C) 2009 Elsevier Ltd. All rights reserved.

In light of reports that the administration of fasudil, a Rho-kinase inhibitor, improved rats locomotor abilities following spinal cord injury, we hypothesized that combining fasudil with another type of therapy, such as stem cell transplantation, might further improve the level of locomotor recovery. Bone marrow stromal cells (BMSCs) are readily available for stem cell therapy. in the present study, we examined whether fasudil combined with BMSC transplantation would produce synergistic effects on recovery. Adult female Sprague-Dawley rats were subjected to spinal cord contusion injury at the T10 vertebral level using an IH impactor (200 Kdyn). Immediately after contusion, they were administrated fasudil intrathecally for 4 weeks. GFP rat-derived BMSCs (2.5x10(6)) were injected into the lesion site 14 days after contusion. Locomotor recovery was assessed for 9 weeks with BBB scoring. Sensory tests were conducted at 8 weeks. Biotinylated dextran amine (BDA) was injected into the sensory-motor cortex at 9 weeks. In addition to an untreated control group, the study also included a fasudil-only group and a BMSC-only group in order to compare the effects of combined therapy vs. single-agent therapy. Animals were perfused transcardially 11 weeks after contusion, and histological examinations were performed. The combined therapy group showed statistically better locomotor recovery than the untreated control group at 8 and 9 weeks after contusion. Neither of the two single-agent treatments improved open field locomotor function. Sensory tests showed no statistically significant difference by treatment. Histological and immunohistochemical studies provided some supporting evidence for better locomotor recovery following combined therapy. The average area of the cystic cavity was significantly smaller in the fasudil+BMSC group than in the control group. The number of 5-HT nerve fibers was significantly higher in the fasudil+BMSC group than in the control group on the rostral side of the lesion site. BDA-labeled fibers on the caudal side of the lesion epicenter were observed only in the fasudil+BMSC group. on the other hand, only small numbers of GFP-labeled grafted cells remained 9 weeks after transplantation, and these were mainly localized at the site of injection. Double immunofluorescence studies showed no evidence of differentiation of grafted BMSCs into glial cells or neurons. The Rho-kinase inhibitor fasudil combined with BMSC transplantation resulted in better locomotor recovery than occurred in the untreated control group. However, the data failed to demonstrate significant synergism from combined therapy compared with the levels of recovery following single-agent treatment. (C) 2009 Elsevier B.V. All rights reserved.

Study Design. To report a new index, the K-line, for deciding the surgical approach for cervical ossification of the posterior longitudinal ligament (OPLL). Objective. To analyze the correlation between the K-line-based classification of cervical OPLL patients and their surgical outcome. Summary of Background Data. Previous studies showed that kyphotic alignment of the cervical spine and a large OPLL are major factors causing poor surgical outcome after laminoplasty for cervical OPLL patients. However, no report has evaluated these 2 factors in 1 parameter. Methods. The K-line was defined as a line that connects the midpoints of the spinal canal at C2 and C7. Twenty-seven patients who had cervical OPLL and underwent posterior decompression surgery were classified into 2 groups according to their K-line classification. OPLL did not exceed the K-line in the K-line (+) group and did exceed it in the K-line (+) group. By intraoperative ultrasonography, we evaluated the posterior shift of the spinal cord after the posterior decompression procedure. The Japanese Orthopedic Association scores before surgery and 1 year after surgery were evaluated, and the recovery rate was calculated. Results. Eight patients were classified as K-line (+), and 19 patients were classified as K-line (+). The mean recovery rate was 13.9% in the K-line (+) group and 66.0% in the K-line (+) group (P &lt; 0.01). Ultrasonography showed that the posterior shift of the spinal cord was insufficient in the K-line (+) group. Conclusion. The present results demonstrate that a sufficient posterior shift of the spinal cord and neurologic improvement will not be obtained after posterior decompression surgery in the K-line (+) group. Our new index, the K-line, is a simple and practical tool for making decisions regarding the surgical approach for cervical OPLL patients.