Tsuyoshi Sakuma

Anomalous vertebral arteries in the extra- and intraosseous regions of the craniovertebral junction visualized by 3-dimensional computed tomographic angiography: analysis of 100 consecutive surgical cases and review of the literature.

Study Design. Consecutive case series and literature review. Objective. To describe the utility of 3-dimensional computed tomographic angiography (3D CTA) for evaluating vertebral artery (VA) anomalies before surgery. Summary of Background Data. Recent advances in instrumentation surgery at the craniovertebral junction (CVJ) enable us to perform rigid internal fixation. However, the risk of VA injury as a complication of the surgery has become a major problem. Thus, the importance of preoperative evaluation of the VA course has been emphasized. Methods. Cases of 100 consecutive patients who underwent CVJ instrumentation surgery since July 1998 were analyzed. Occipitocervical/thoracic or C1–C2 posterior fusion was performed for atlantoaxial subluxation (AAS) in 59 patients and cervical fixation including C2 was required for middle-to-lower cervical lesions in 41 patients. Twenty-seven patients with AAS had a congenital skeletal anomaly (CSA) at the CVJ including os odontoideum and occipitalization of C1 (AAS-CSA[+] group). Anomalous VAs at the extra- and intraosseous regions were evaluated by 3D CTA. Results. No neurovascular injury occurred during surgery. Abnormal courses of the VA at the extraosseous region were detected in 10 cases: 2 had fenestration and 8 had a persistent first intersegmental artery. All 10 cases were in the AAS-CSA(+) group. A high-riding VA was detected in 31 cases. Fourteen out of the 31 cases were in the AAS-CSA(+) group, indicating 51.9% of the AAS-CSA(+) group had high-riding VA. In the AAS-CSA(+) group, a C1–C2 transarticular screw and C2 pedicle screw were actually inserted in 58% and 31% of the planned insertions, respectively. Conclusion. The present findings suggest that the frequency of an abnormal VA at the extra- and intraosseous regions is increased when patients have AAS and CSA at the CVJ. Using preoperative 3D CTA, we can precisely identify anomalous VAs and thereby reduce the risk of their intraoperative injury.

C5 palsy following anterior decompression and spinal fusion for cervical degenerative diseases

Postoperative C5 palsy is a common complication after cervical spine decompression surgery. However, the incidence, prognosis, and etiology of C5 palsy after anterior decompression with spinal fusion (ASF) have not yet been fully established. In the present study, we analyzed the clinical and radiological characteristics of patients who developed C5 palsy after ASF for cervical degenerative diseases. The cases of 199 consecutive patients who underwent ASF were analyzed to clarify the incidence of postoperative C5 palsy. We also evaluated the onset and prognosis of C5 palsy. The presence of high signal changes (HSCs) in the spinal cord was analyzed using T2-weighted magnetic resonance images. C5 palsy occurred in 17 patients (8.5%), and in 15 of them, the palsy developed after ASF of 3 or more levels. Among ten patients who had a manual muscle test (MMT) grade ≤2 at the onset, five patients showed incomplete or no recovery. Sixteen of the 17 C5 palsy patients presented neck and shoulder pain prior to the onset of muscle weakness. In the ten patients with a MMT grade ≤2 at the onset, nine patients showed HSCs at the C3–C4 and C4–C5 levels. The present findings demonstrate that, in most patients with severe C5 palsy after ASF, pre-existing asymptomatic damage of the anterior horn cells at C3–C4 and C4–C5 levels may participate in the development of motor weakness in combination with the nerve root lesions that occur subsequent to ASF. Thus, when patients with spinal cord lesions at C3–C4 and C4–C5 levels undergo multilevel ASF, we should be alert to the possible occurrence of postoperative C5 palsy.

Efficacy and reliability of highly functional open source DICOM software (OsiriX) in spine surgery

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.

Accuracy of Pedicle Screw Placement in Scoliosis Surgery: A Comparison between Conventional Computed Tomography-Based and O-Arm-Based Navigation Techniques.

Study Design Retrospective study. Purpose We compared the accuracy of O-arm-based navigation with computed tomography (CT)-based navigation in scoliotic surgery. Overview of Literature No previous reports comparing the results of O-arm-based navigation with conventional CT-based navigation in scoliotic surgery have been published. Methods A total of 222 pedicle screws were implanted in 29 patients using CT-based navigation (group C) and 416 screws were implanted in 32 patients using O-arm-based navigation (group O). Postoperative CT was performed to assess the screw accuracy, using the established Neo classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation ≥2 and <4, and grade 3: perforation ≥4 mm). Results In group C, 188 (84.7%) of the 222 pedicle screw placements were categorized as grade 0, 23 (10.4%) were grade 1, 11 (5.0%) were grade 2, and 0 were grade 3. In group O, 351 (84.4%) of the 416 pedicle screw placements were categorized as grade 0, 52 (12.5%) were grade 1, 13 (3.1%) were grade 2, and 0 were grade 3. Statistical analysis showed no significant difference in the prevalence of grade 2.3 perforations between groups C and O. The time to position one screw, including registration, was 10.9±3.2 minutes in group C, but was significantly decreased to 5.4±1.1 minutes in group O. Conclusions O-arm-based navigation facilitates pedicle screw insertion as accurately as conventional CT-based navigation. The use of O-arm-based navigation successfully reduced the time, demonstrating advantages in the safety and accuracy of pedicle screw placement for scoliotic surgery.

Multicenter Prospective Nonrandomized Controlled Clinical Trial to Prove Neurotherapeutic Effects of Granulocyte Colony-stimulating Factor for Acute Spinal Cord Injury: Analyses of Follow-up Cases After at Least 1 Year

Study Design. An open-labeled multicenter prospective nonrandomized controlled clinical trial. Objective. To confirm the feasibility of using granulocyte colony-stimulating factor (G-CSF) for treatment of acute spinal cord injury (SCI). Summary of Background Data. We previously reported that G-CSF promotes functional recovery after compression-induced SCI in mice. On the basis of these findings, we conducted a multicenter prospective controlled clinical trial to assess the feasibility of G-CSF therapy for patients with acute SCI. Methods. The trial ran from August 2009 to March 2011, and included 41 patients with SCI treated within 48 hours of onset. Informed consent was obtained from all patients. After providing consent, patients were divided into 2 groups. In the G-CSF group (17 patients), G-CSF (10 &mgr;g/kg/d) was intravenously administered for 5 consecutive days, and in the control group (24 patients), patients were similarly treated except for the G-CSF administration. We evaluated motor and sensory functions using the American Spinal Cord Injury Association score and American Spinal Cord Injury Association impairment scale at 1 week, 3 months, 6 months, and 1 year after onset. Results. Only 2 patients did not experience American Spinal Cord Injury Association impairment scale improvement in the G-CSF group. In contrast, 15 patients in the control group did not experience American Spinal Cord Injury Association impairment scale improvement. In the analysis of increased American Spinal Cord Injury Association motor score, a significant increase in G-CSF group was detected from 1 week after the administration compared with the control group. After that, some spontaneous increase of motor score was detected in control group, but the significant increase in G-CSF group was maintained until 1 year of follow-up. Conclusion. Despite the limitation that patient selection was not randomized, the present results suggest the possibility that G-CSF administration has beneficial effects on neurological recovery in patients with acute SCI. Level of Evidence: 3

Neuroprotective Therapy Using Granulocyte Colony-Stimulating Factor for Patients With Worsening Symptoms of Thoracic Myelopathy A Multicenter Prospective Controlled Trial

Study Design. An open-labeled multicenter prospective controlled clinical trial. Objective. To confirm the feasibility of granulocyte colony–stimulating factor (G-CSF) administration for patients with thoracic myelopathy. Summary of Background Data. Although G-CSF is best known as an important cytokine commonly used to treat neutropenia, it also has nonhematopoietic functions. Previous experimental studies have shown that G-CSF can enhance tissue regeneration of several organs, such as the heart and the brain. We previously reported that G-CSF promotes functional recovery after spinal cord injury in rodents. On the basis of those findings, we started a clinical trial of neuroprotective therapy, using G-CSF for patients with worsening symptoms of thoracic myelopathy. Methods. Patients whose Japanese Orthopaedic Association (JOA) score for thoracic myelopathy had decreased 2 points or more during a recent 1-month period were eligible for entry. After giving informed consent, patients were assigned to G-CSF and control groups. The G-CSF group (n = 10) received G-CSF 10 &mgr;g/kg per day intravenously for 5 consecutive days. The control group (n = 14) received similar treatments as the G-CSF group except for G-CSF administration. The primary outcome was JOA recovery rate at 1 month after G-CSF administration or initial treatment. Results. There was greater improvement in neurological functioning between baseline and 1-month follow-up in the G-CSF group (JOA recovery rate: 29.1 ± 20.5%) than in the control group (JOA recovery rate: 1.1 ± 4.2%) (P < 0.01). No serious adverse events occurred during or after the G-CSF administration. Conclusion. The results provide evidence that G-CSF administration caused neurological recovery in patients with worsening symptoms of thoracic compression myelopathy.

Granulocyte colony-stimulating factor attenuates spinal cord injury-induced mechanical allodynia in adult rats.

Spinal cord injury (SCI) can cause neuropathic pain (NeP), often reducing a patients quality of life. We recently reported that granulocyte colony-stimulating factor (G-CSF) could attenuate NeP in several SCI patients. However, the mechanism of action underlying G-CSF-mediated attenuation of SCI-NeP remains to be elucidated. The purpose of the present study was to elucidate the therapeutic effect and mechanism of action of granulocyte colony-stimulating factor for SCI-induced NeP. T9 level contusive SCI was introduced to adult male Sprague Dawley rats. Three weeks after injury, rats received intraperitoneal recombinant human G-CSF (15.0 μg/kg) for 5 days. Mechanical allodynia was assessed using von Frey filaments. Immunohistochemistry and western blot analysis were performed in spinal cord lumbar enlargement samples. Testing with von Frey filaments showed significant increase in the paw withdrawal threshold in the G-CSF group compared with the vehicle group 4 weeks, 5 weeks, 6 weeks and 7 weeks after injury. Immunohistochemistry for CD11b (clone OX-42) revealed that the number of OX-42-positive activated microglia was significantly smaller in the G-CSF group than that in the vehicle rats. Western blot analysis indicated that phosphorylated-p38 mitogen-activated protein kinase (p38MAPK) and interleukin-1β expression in spinal cord lumbar enlargement were attenuated in the G-CSF-treated rats compared with that in the vehicle-treated rats. The present results demonstrate a therapeutic effect of G-CSF treatment for SCI-induced NeP, possibly through the inhibition of microglial activation and the suppression of p38MAPK phosphorylation and the upregulation of interleukin-1β.

Cervical myelopathy in patients with athetoid cerebral palsy.

Study Design. Retrospective clinical study. Objective. To report the surgical outcomes of patients with cervical myelopathy associated with athetoid cerebral palsy and to assess whether a halo vest is necessary for postoperative external immobilization. Summary of Background Data. Although a halo vest has remained the first choice for postoperative external immobilization of patients with cervical myelopathy associated with cerebral palsy, simplification of this method has been attempted in recent years. Studies focusing on postoperative external immobilization are rare. Methods. Since 2001, 20 patients underwent surgery with posterior instrumented fusion or posterior fixation and anterior decompression with fusion with a year or longer follow-up. Before 2004, all patients were given a halo vest for postoperative external immobilization. After 2004, halo vests were not used, and when abnormal involuntary neck movements were severe, an intramuscular injection of botulinum toxin was administered before and after surgery. Surgical outcomes, surgical methods and complications were compared between the group that used a halo vest and the group that did not use a halo vest. Results. In the halo vest group, the average Japanese Orthopedic Association score was 6.9 points before surgery and 9.3 points at 1-year follow-up. The average recovery rate was 25.0%. In the group without halo vest use, the average Japanese Orthopedic Association score was 5.8 points before surgery and 9.9 points at 1-year follow-up. The average recovery rate was 35.7%. The group without halo vest use achieved outcomes equal to those achieved in the group with halo vest use. The frequency of complications was less without halo vest use than with halo vest use. Conclusion. No inferiority in clinical outcomes was seen if postoperative halo vest use was omitted. Progress in surgical instrumentation and injection of botulinum toxin may explain this result.

Spinal fusion on adolescent idiopathic scoliosis patients with the level of L4 or lower can increase lumbar disc degeneration with sagittal imbalance 35 years after surgery

Introduction The purpose of this study was to investigate the long-term incidence of lumbar disc degeneration and Modic changes in the non-fused segments of patients with adolescent idiopathic scoliosis (AIS) who previously underwent spinal fusion. Methods Study subjects consisted of 252 patients with AIS who underwent spinal fusion between 1968 and 1988. Of 252 patients, 35 subjects underwent lumbar spine MRI and whole spine X-ray examination. The mean patient age at the time of follow-up was 49.8 years, with an average follow-up period of 35.1 years. We classified the subjects into two groups based on the lowest fused vertebra: H group whose lowest fused vertebra was L3 or higher levels and L group whose lowest fused vertebra was L4 or lower levels. Results The L group had significantly advanced disc degeneration on MRI. There was no significant difference between two groups in Modic changes. The L group showed less lumbar lordosis than the H group (H group: 48.1 degrees; and L group: 32.1 degrees) and greater SVA (H group: 1.2 cm; and L group: 5.5 cm). Conclusions In AIS patients, 35 years after spinal fusion surgery on average, we evaluated lumbar disc degeneration and Modic changes of the non-fused segments. In patients with the lowest fusion level at L4 or lower, there were reduced lumbar lordosis, considerable SVA imbalance, and severe disc degeneration compared with those with the lowest fusion level at L3 or higher. The lowest fusion level at L3 or higher is recommended to reduce disc degeneration in midlife.

Transplanted peripheral blood stem cells mobilized by granulocyte colony-stimulating factor promoted hindlimb functional recovery after spinal cord injury in mice

Granulocyte colony-stimulating factor (G-CSF) mobilizes peripheral blood stem cells (PBSCs) derived from bone marrow. We hypothesized that intraspinal transplantation of PBSCs mobilized by G-CSF could promote functional recovery after spinal cord injury. Spinal cords of adult nonobese diabetes/severe immunodeficiency mice were injured using an Infinite Horizon impactor (60 kdyn). One week after the injury, 3.0 μl of G-CSF-mobilized human mononuclear cells (MNCs; 0.5 × 105/μl), G-CSF-mobilized human CD34-positive PBSCs (CD34; 0.5 × 105/μl), or normal saline was injected to the lesion epicenter. We performed immunohistochemistry. Locomotor recovery was assessed by Basso Mouse Scale. The number of transplanted human cells decreased according to the time course. The CD31-positive area was significantly larger in the MNC and CD34 groups compared with the vehicle group. The number of serotonin-positive fibers was significantly larger in the MNC and CD34 groups than in the vehicle group. Immunohistochemistry revealed that the number of apoptotic oligodendrocytes was significantly smaller in cell-transplanted groups, and the areas of demyelination in the MNC- and CD34-transplanted mice were smaller than that in the vehicle group, indicating that cell transplantation suppressed oligodendrocyte apoptosis and demyelination. Both the MNC and CD34 groups showed significantly better hindlimb functional recovery compared with the vehicle group. There was no significant difference between the two types of transplanted cells. Intraspinal transplantation of G-CSF-mobilized MNCs or CD34-positive cells promoted angiogenesis, serotonergic fiber regeneration/sparing, and preservation of myelin, resulting in improved hindlimb function after spinal cord injury in comparison with vehicle-treated control mice. Transplantation of G-CSF-mobilized PBSCs has advantages for treatment of spinal cord injury in the ethical and immunological viewpoints, although further exploration is needed to move forward to clinical application.