High reliability and accuracy of dynamic magnetic resonance imaging in the diagnosis of cervical Spondylotic myelopathy: a multicenter study.

BACKGROUND: Cervical spondylotic myelopathy (CSM) is a critical condition that results in significant neurologic deterioration. An accurate diagnosis is essential for determining its outcome and prognosis. The pathology is strongly associated with dynamic factors; therefore, dynamic magnetic resonance (MR) image could be crucial to accurately detect CSM. However, very few studies have evaluated the reliability and accuracy of dynamic MR in CSM. In this study, we aimed to compare intra- and interobserver reliabilities and accuracy of dynamic MR in detecting CSM using sagittal MR scans of the neck in the flexed, neutral, and extended position. METHODS: Out of 131 patients who underwent surgical treatments for CSM, 107 were enrolled in this study. The patient underwent three-types of sagittal MR scans that were obtained separately in different neck positions (neutral, flexion, and extension postures). The MR scans of the cervical spine were evaluated independently by three spine professionals, on the basis of tabled questionnaires. For accuracy, we performed a receiver operator characteristic analysis, and the overall discriminating ability of each method was measured by calculating the area under the ROC curve. The Cohen's kappa coefficient and the Fleiss-generalized kappa coefficient was used to the inter- and intra-observer reliabilities. RESULTS: The intraobserver reliability (using the Cohen's kappa coefficient) and interobserver reliability (using the Fless kappa coefficient) were respectively 0.64 and 0.52 for the neutral sagittal MR. The accuracy of neutral sagittal MR in detecting CSM was 0.735 (95% CI, 0.720 to 0.741) while that of extension sagittal MRI was 0.932 (96% CI, 0.921 to 0.948). CONCLUSIONS: Dynamic MR significantly showed better diagnostic reliability and accuracy in detecting CSM compared to conventional MR. In particular, extension MR scans could provide a more accurate diagnosis than other images.

Clinical and radiological outcomes between biportal endoscopic decompression and microscopic decompression in lumbar spinal stenosis.

BACKGROUND CONTEXT: Numerous minimal invasive techniques treating lumbar spinal stenosis have been introduced. Clinical results using biportal endoscopic spinal surgery has recently been introduced as a treatment option for lumbar spinal stenosis. The purpose of this study was to compare the clinical and radiologic outcome between microscopic unilateral laminotomy bilateral decompression and biportal endoscopic unilateral laminotomy bilateral decompression in patients with degenerative lumbar spinal stenosis. METHOD: A total of 89 patients were evaluated for this study. Only single-level patients were enrolled for accurate comparison. Patients that underwent biportal endoscopic surgery were assigned to Group A, and patients that underwent microscopic surgery were designated Group B. Clinical outcomes were evaluated using modified Macnab criteria, Oswestry Disability Index, and Visual Analog Scale. Postoperative complications were checked until final follow up. Plain radiographs before and after surgery were compared to analyze the change of alignment. RESULT: There was a significant difference between Group A and B in VAS of back on postoperative 2 months. Other clinical measurements except for postoperative 2 months VAS of back showed no significant difference. There were no significant differences between Group A and Group B regarding preoperative and postoperative radiological findings. CONCLUSION: Two different decompression techniques preserve the spinal structure and exhibit a favorable clinical outcome and have the advantage of not causing postoperative instability in the short term follow up. Biportal endoscopic surgery may leads to less postoperative back pain than microscopic surgery, which may allow early ambulation and shorter hospitalization period.

Neuropeptide Y regulates the hematopoietic stem cell microenvironment and prevents nerve injury in the bone marrow.

Many reports have revealed the importance of the sympathetic nervous system (SNS) in the control of the bone marrow environment. However, the specific role of neuropeptide Y (NPY) in this process has not been systematically studied. Here we show that NPY-deficient mice have significantly reduced hematopoietic stem cell (HSC) numbers and impaired regeneration in bone marrow due to apoptotic destruction of SNS fibers and/or endothelial cells. Furthermore, pharmacological elevation of NPY prevented bone marrow impairments in a mouse model of chemotherapy-induced SNS injury, while NPY injection into conditional knockout mice lacking the Y1 receptor in macrophages did not relieve bone marrow dysfunction. These results indicate that NPY promotes neuroprotection and restores bone marrow dysfunction from chemotherapy-induced SNS injury through the Y1 receptor in macrophages. They also reveal a new role of NPY as a regulator of the bone marrow microenvironment and highlight the potential therapeutic value of this neuropeptide.

Neuropeptide Y Induces Hematopoietic Stem/Progenitor Cell Mobilization by Regulating Matrix Metalloproteinase-9 Activity Through Y1 Receptor in Osteoblasts.

Hematopoietic stem/progenitor cell (HSPC) mobilization is an essential homeostatic process regulated by the interaction of cellular and molecular components in bone marrow niches. It has been shown by others that neurotransmitters released from the sympathetic nervous system regulate HSPC egress from bone marrow to peripheral blood. In this study, we investigate the functional role of neuropeptide Y (NPY) on this process. NPY deficient mice had significantly impaired HSPC mobilization due to increased expression of HSPC maintenance factors by reduction of matrix metalloproteinase-9 (MMP-9) activity in bone marrow. Pharmacological or endogenous elevation of NPY led to decrease of HSPC maintenance factors expression by activating MMP-9 in osteoblasts, resulting in HSPC mobilization. Mice in which the Y1 receptor was deleted in osteoblasts did not exhibit HSPC mobilization by NPY. Furthermore, NPY treatment in ovariectomized mice caused reduction of bone loss due to HSPC mobilization. These results suggest a new role of NPY on HSPC mobilization, as well as the potential therapeutic application of this neuropeptide for stem cell-based therapy. Stem Cells 2016;34:2145-2156.

Occipitocervical inclination: new radiographic parameter of neutral occipitocervical position.

PURPOSE: To describe occipitocervical inclination (OCI), a new parameter that could compensate for defects in existing radiographic parameters, and to define occipitocervical neutral position. METHODS: Neutral, flexion, and extension lateral cervical spine radiographs of 200 patients (100 male and 100 female patients) judged to be normal were analyzed. The mean age was 45.19 years (range 11-74; 42.84 for male and 47.53 for female patients). For OCI, the angle formed by the line connecting the posterior border of the C4 vertebral body and McGregor's line was measured. Occipitocervical angle (OCA) and occipitocervical distance (OCD) were measured and compared with OCI. RESULTS: OCI on standard, neutral lateral cervical radiographs was 102.51° ± 8.87°. There was no significant gender difference in neutral OCI 102.81° ± 7.93° for male and 102.21° ± 9.74° for female patients (P = 0.631). The mean neutral OCA was 38.69° ± 9.23°, and the mean neutral OCD was 22.98 ± 5.10 mm. Pearson's correlation coefficient for the value of the cervical lordosis angle and that of neutral OCI was r = 0.274 (P < 0.001). Intraclass correlation coefficient values for inter- and intraobserver reliability for OCI were significantly higher than those for OCA (P < 0.001) and tended to be higher than those for OCD (P = 0.087). CONCLUSIONS: OCI is a very useful parameter for the determination of neutral position during occipitocervical fusion for patients with altered C0-C2 anatomy.

Cervical subtotal en-bloc spondylectomy of C6 mesenchymal chondrosarcoma.

INTRODUCTION: We present a case of C6 mesenchymal chondrosarcoma and discuss safe posterior to anterior approach subtotal en-bloc spondylectomy. MATERIALS AND METHODS: A 29-year-old male consulted for our department with severe posterior neck pain doing exercise. CT scan demonstrated a primary osteolytic lesion on C6 left transverse foramen and MRI demonstrated the tumor involved C6 vertebra from layers B, C and F sectors 4-6 encasing left vertebral artery. Preoperatively neurointerventional radiology service occluded the left vertebral artery and tumor feeding artery using coil embolization. Posterior approach consist of C5-C7 laminectomy, left sided C6 and C7 nerve root sacrifice, posterior disc removal and release of C5-6-7 and posterior reconstruction. Then, position was changed to supine, and the anterior approach was followed as C5-6, C6-7 discectomy, left vertebral artery ligation and cut, longus coli resection and C6 subtotal spondylectomy with en-bloc resection of mass, mesh cage insertion and C5-C7 anterior plate fixation. During operation, frozen biopsy was performed on 8 areas (longus coli, lateral margin, anteroinferior margin, posterior margin, posterosuperior margin, C5 transverse foramen, posteroinferior margin, inferior margin) after wide resection. Tumor free margin was confirmed. RESULTS: After operation, he complained of tingling sensation of left thumb and forearm medial side, and elbow extensor motor grade was checked to 4/5 postoperatively. In the followed-up radiograph, the tumor was completely removed, and the instability of joint was not seen. As a result of observing follow-up CT at a year after the surgery, recurrence findings have not been shown up to now, and the progression of neurologic symptoms has not been shown either. CONCLUSION: Based on the Grand Round case and relevant literature, we discuss the case of mesenchymal chondrosarcoma occurring from the C6 cervical spine treated with cervical subtotal en-bloc spondylectomy. Successful en-bloc resection of the tumor was achieved using posterior to anterior approach.

Optimal angle of needle insertion for fluoroscopy-guided transforaminal epidural injection of L5.

BACKGROUND: Unlike other sites, there is difficulty in performing TFESI at the L5-S1 level because the iliac crest is an obstacle to needle placement. OBJECTIVE: The objective of this study was to identify the optimal angle of fluoroscopy for insertion and advancement of a needle during L5 TEFSI. METHODS: We conducted an observational study of patients undergoing fluoroscopy-guided L5 TFESI in the prone position. A total of 80 patients (40 men and 40 women) with radiating pain of lower limbs were enrolled. During TFESI, we measured the angle at which the L5 vertebral body forms a rectangular shape and compared men and women. Then, we measured area of safe triangle in tilting angle of fluoroscopy from 15° to 35° and compared men and women. RESULTS: The mean cephalocaudal angle, where the vertebral body takes the shape of a rectangle, was 11.0° in men and 13.9° in women (P = 0.007). In men, the triangular area was maximal at 18.3 mm² with an oblique view angle of 25°. In women, the area was maximal at 23.6 mm² with an oblique view angle of 30°. At an oblique view angle of 30° and 35°, the area was significantly greater in women (P < 0.05). CONCLUSION: When TFESI is performed at the L5 region in the prone position, placement of fluoroscopy at a cephalocaudal angle of 11.0° and an oblique angle of 25° in men and cephalocaudal angle of 13.9° and an oblique angle of 30° in women would be most reasonable.

Comparison and correlation of pelvic parameters between low-grade and high-grade spondylolisthesis.

STUDY DESIGN: This study was retrospectively conducted on 51 patients with L5-S1 spondylolisthesis. OBJECTIVE: This study was conducted to compare a total of 11 pelvic parameters, such as the level of displacement by Meyerding method, lumbar lordosis, sacral inclination, lumbosacral angle, slip angle, S2 inclination, pelvic incidence (PI), L5 inclination, L5 slope, pelvic tilt (PT), and sacral slope (SS) between low-grade and high-grade spondylolisthesis, and to investigate a correlation of the level of displacement by Meyerding method with other pelvic parameters. METHODS: Pelvic parameters were measured using preoperational erect lateral spinal simple radiographs. The patients were divided into 39 patients with low-grade spondylolisthesis and 12 patients with high-grade spondylolisthesis before analysis. In all patients of both groups, 11 radiographic measurements including the level of displacement by Meyerding method, lumbar lordosis, sacral inclination, lumbosacral angle, slip angle, S2 inclination, PI, L5 inclination, L5 slope, PT, and SS were performed. T test and Pearson correlation analysis were conducted to compare and analyze each measurement. RESULTS: As for the comparison between the 2 groups, a statistically great significance in the level of displacement by Meyerding method, lumbosacral angle, slip angle, L5 incidence, PI, and L5 slope (P≤0.001) was shown. Meanwhile, a statistical significance in the sacral inclination and PT (P<0.05) was also shown. However, no statistical significance in the S2 incidence and SS was shown. A correlation of the level of displacement by Meyerding method with each parameter was analyzed in the both the groups. A high correlation was observed in the lumbar lordosis, lumbosacral angle, slip angle, L5 incidence, and L5 slope (Pearson correlation coefficient, P=0.01), as well as the sacral inclination, PI, and PT (Pearson correlation coefficient, P=0.05). Meanwhile, no correlation was shown in the S2 incidence and SS. CONCLUSIONS: A significant difference in the lumbosacral angle, slip angle, L5 incidence, PI, L5 slope, sacral inclination, and PT was shown between the patients with high-grade spondylolisthesis and patients with low-grade spondylolisthesis. Among the aforementioned measurements, the PI showed a significant difference between the 2 groups and also had a significant correlation with the dislocation level in all the patients.

Analysis of cervical pedicle with reconstructed computed tomography imaging in Korean population: feasibility and surgical anatomy.

STUDY DESIGN: We analyzed the anatomy of C3-C6 cervical pedicles with reconstructed computed tomography images. OBJECTIVES: The objective of the study was to estimate the feasibility and to understand the surgical anatomy in order to reduce pedicle penetration. SUMMARY OF BACKGROUND DATA: It is necessary to minimize pedicle penetration by anatomic analysis of cervical pedicles. Many studies have been conducted on cervical pedicle anatomy and cervical pedicle screw fixation, yet there are debates about the feasibility and surgical anatomy. METHODS: Oblique axial and oblique sagittal images were reconstructed from a 1 mm cut computed tomography image. The pedicle transverse diameter, pedicle length, pedicle convergence angle (CA), and pedicle distance were measured on the oblique axial images. The pedicle sagittal diameter, pedicle sagittal angle (SA), and lateral mass index were measured on the oblique sagittal images. The multiple t test was used for statistical analysis. RESULTS: The averages of the pedicle transverse diameter ranged from 5.79 to 6.19 mm, the pedicle length ranged from 16.24 to 17.56 mm, the CA ranged from 47.49 to 48.86 degrees, the pedicle distance ranged from 22.67 to 24.93 mm, the SA ranged from -15.43 to 19.98 degrees, and the lateral mass index ranged from 0.64 to 1.25. CONCLUSIONS: Because of a tight safe margin, to reduce pedicle penetration the screw should be inserted along the pedicle. With regard to SA, C3 and C4 have a risk of upper end plate penetration. However, C5 and C6 have a risk of facet joint violation, which needs C4 and C5 inferior articular process removal for screw placement. The entry point at C3 and C4 is near one third of the lateral mass height from the posterior border of the superior articular process at the posterolateral border of the lateral mass. The entry point at C5 is near the posterolateral border of the superior articular process and that at C6 is superior to the posterior border of the superior articular process at a line medial to the posterolateral border of the C5 lateral mass. During insertion, not only CA but even SA should be considered carefully to reduce pedicle penetration.

The incidence and the risk factors of venous thromboembolism in Korean patients with pelvic or acetabular fractures.

BACKGROUND: Pelvic ring and acetabular fractures are the results of high energy trauma, but there is a paucity of information available regarding the incidence and risk factors of venous thromboembolism (VTE) after these injuries in Asians. This study was undertaken to evaluate the incidence of VTE after a pelvic or an acetabular fracture and to identify predictive factors. METHODS: A prospective evaluation was performed by indirect computed tomography (CT) venography in patients with pelvic or acetabular fractures. Ninety-five patients were examined by indirect CT venography. Fifty-five patients suffered from a pelvic ring injury (anteroposterior compression 5, lateral compression 25, vertical shear 25), and the remaining 40 from acetabular fractures (simple 18, complex 22). Indirect CT venography was performed within 1-2 weeks of initial trauma. Relationships between VTE and sex, age, fracture pattern, body mass index, injury severity score, period of immobilization, and need for surgical treatment were analyzed. Deep vein thrombosis (DVT) in a more proximal to popliteal vein and the existence of PE were considered clinically significant. RESULTS: Thirty-two patients (33.7 %) were found to have VTE at an average of 11 days after initial injury. Clinically significant DVT was found 20 cases (21.1 %). No statistical difference was found between pelvic ring injuries and acetabular fractures with respect to the development of VTE. For those with pelvic ring injury, the incidence of VTE in those with a vertical shear injury (52 %) was significantly greater than in others with a pelvic ring injury (p = 0.014). Patients with an age >50 were found to be at greater risk of VTE (p = 0.032). CONCLUSION: Our findings demonstrate that Korean patients with pelvic or acetabular fractures have a higher risk of VTE than is generally believed, and caution should be taken to prevent and treat VTE, especially in high energy pelvic ring injury and elderly patients.

Brain-Derived Neurotrophic Factor (BDNF) Enhances Osteogenesis and May Improve Bone Microarchitecture in an Ovariectomized Rat Model.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) has gained attention as a therapeutic agent due to its potential biological activities, including osteogenesis. However, the molecular mechanisms involved in the osteogenic activity of BDNF have not been fully understood. This study aimed to investigate the action of BDNF on the osteoblast differentiation in bone marrow stromal cells, and its influence on signaling pathways. In addition, to evaluate the clinical efficacy, an in vivo animal study was performed. METHODS: Preosteoblast cells (MC3T3-E1), bone marrow-derived stromal cells (ST2), and a direct 2D co-culture system were treated with BDNF. The effect of BDNF on cell proliferation was determined using the CCK-8 assay. Osteoblast differentiation was assessed based on alkaline phosphatase (ALP) activity and staining and the protein expression of multiple osteoblast markers. Calcium accumulation was examined by Alizarin red S staining. For the animal study, we used ovariectomized Sprague-Dawley rats and divided them into BDNF and normal saline injection groups. MicroCT, hematoxylin and eosin (H&E), and tartrate-resistant acid phosphatase (TRAP) stain were performed for analysis. RESULTS: BDNF significantly increased ALP activity, calcium deposition, and the expression of osteoblast differentiation-related proteins, such as ALP, osteopontin, etc., in both ST-2 and the MC3T3-E1 and ST-2 co-culture systems. Moreover, the effect of BDNF on osteogenic differentiation was diminished by blocking tropomyosin receptor kinase B, as well as inhibiting c-Jun N-terminal kinase and p38 MAPK signals. Although the animal study results including bone density and histology showed increased osteoblastic and decreased osteoclastic activity, only a portion of parameters reached statistical significance. CONCLUSIONS: Our study results showed that BDNF affects osteoblast differentiation through TrkB receptor, and JNK and p38 MAPK signal pathways. Although not statistically significant, the trend of such effects was observed in the animal experiment.

Percutaneous iliosacral screwing in pelvic ring injury using three-dimensional fluoroscopy.

BACKGROUND: Iliosacral screw fixation is a popular technique for treatment of unstable pelvic injuries involving the posterior ring. However, screw malposition may result in dangerous complications involving injury to adjacent neurovascular structures. This study was conducted in order to evaluate the results and efficacy of using three-dimensional fluoroscopy in the performance of iliosacral screw fixation. METHODS: Twenty-nine patients (31 cases, two bilateral) who suffered injury to the pelvic ring requiring surgical treatment were included in this study. According to the Association for Osteosynthesis-Orthopaedic Trauma Association (AO-OTA) classification, there were 14 patients with type B, 13 patients with type C, and 2 patients with a bilateral sacral fracture. The mean age of patients was 39 years. Once the guide pin had been inserted, its safety was confirmed using three-dimensional fluoroscopy; screw fixation was then performed. Eighteen patients underwent percutaneous iliosacral screw fixation and anterior fixation, while 11 patents underwent screw fixation only. Postoperative computed tomography (CT) was performed for evaluation of the screw position, including any invasion into the sacral foramen or canal and neurovascular injury. The perforation of the screw was divided according to the location (sacral zones I, II, and III) and the degree (grade 0, no perforation; grade 1, perforation <2 mm; grade 2, perforation between 2 and 4 mm; grade 3, perforation >4 mm). RESULTS: The mean operation time was 35.6 min, and the mean radiation exposure time was 85.9 s. For accurate location of the guide pin, one patient underwent three-dimensional reconstruction twice. None of the patients required reoperation or suffered any neurovascular injury. Although seven cases involved perforation, all were less than 2 mm (grade 0: 24 cases, grade 1: 7 cases). CONCLUSIONS: When performing percutaneous iliosacral screw fixation in a patient with an unstable pelvic ring injury, use of three-dimensional fluoroscopy may allow for accurate location of the screw and result in fewer complications.

Operative treatment of Freiberg disease using extra-articular dorsal closing-wedge osteotomy: technical tip and clinical outcomes in 13 patients.

BACKGROUND: Extra-articular dorsal closing wedge osteotomy has been used with successful results for Freiberg disease; however, there has been concern regarding the technical difficulty. The purpose of this study was to address technical tips and report on the clinical and radiographic outcome using Kirchner wire-assisted dorsal closing wedge osteotomy. METHODS: A retrospective review of 13 patients with a mean age of 29.1 years was conducted. Extra-articular dorsal wedge osteotomy was performed after debridement of the joint. Two Kirschner wires were inserted and used as a joystick to manipulate the osteotomized bone. The osteotomy site was fixed with crossed pins. Clinical outcome was assessed according to American Orthopaedic Foot and Ankle Society score, range of motion of the metatarsophalangeal joint, and visual analogue scale. Head necrosis was classified according to Smillie stage; time to bone union and metatarsal shortening were reviewed. Patients were followed for a mean period of 44.2 months. RESULTS: Mean American Orthopaedic Foot and Ankle Society score at the latest follow-up was 92.2 (range, 92-100). The range of motion of the metatarsophalangeal joint showed a mean increase of 6.2 degrees (range, -10 to 25) at the latest follow-up. The mean visual analogue scale score decreased from 7.5 (range, 5-10) preoperatively to 1 (range, 0-4) at the latest follow-up (P < .01). All osteotomies healed on average after 7.0 weeks (range, 4-13.6) without nonunion. The average metatarsal shortening was 0.5 mm (range, -3.1 to 3.5). None of the patients showed progression of osteonecrosis or joint space narrowing. CONCLUSION: Extra-articular closing dorsal wedge osteotomy can yield good articular congruity with bone remodeling, with easy performance of the procedure with temporary Kirschner wires without complication. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Surgical outcome of locked facet in distractive flexion injury of the subaxial cervical spine: Single institution retrospective study.

The optimal surgical treatment for patients suffering from distractive flexion injury of the subaxial cervical spine with a locked facet (LF) is unknown. Closed reduction via an anterior or posterior approach is a treatment option for LF. We examined the surgical outcomes of patients treated for locked facet distractive flexion injury (LF-DFI) in this case series, with a particular emphasis on the surgical approach and reduction maneuver. We retrospectively analyzed the patients with distractive flexion injury of the subaxial cervical spine who underwent surgery at our hospital between November 2006 and April 2021. Patients who did not have facet subluxation or dislocation or those who achieved LF reduction prior to skin incision were excluded from this study. The patients were divided into 2 groups based on their initial approach, anterior or posterior approach. Perioperative clinical outcomes, including the American Spinal Cord Injury Association scale score, radiological changes, and complications were analyzed. This study enrolled 12 patients with LF-DFI. Four and 8 patients underwent the anterior and posterior approaches, respectively. The LF was reduced using an anterior approach with traction between the vertebral bodies in the anterior approach group and using a posterior approach with partial facetectomy in the posterior approach group. The preoperative American Spinal Cord Injury Association scale scores were as follows: A, 1 patient; B, 1 patient; C, 3 patients; D, 4 patients; and E, 3 patients. Nine patients showed no neurologic deterioration after surgery, whereas 2 had an aggravated neurologic status. Postoperatively, patients who underwent posterior open reduction did not exhibit worsened neurologic symptoms, whereas 2 patients who underwent the anterior approach showed worsened neurologic symptoms. At the final follow-up, all patients achieved radiological fusion, and no complications other than neurologic deterioration were identified. In terms of worsening postoperative neurologic status, a posterior approach using partial facetectomy for LF reduction is considered a safer surgical technique than an anterior approach. To avoid iatrogenic intraoperative cord injury, we recommend posterior approach in patients with LF-DFI.

Anatomical Consideration for Anterior Approach of Cervicothoracic Junction: A Computed Tomography Image Analysis.

Background: In the cervicothoracic junction (CTJ), there is limited working space to perform the posterior-only approach. Therefore, a combined anterior approach is required in some cases. However, the great vessels and sternum obstruct the anterior corridor and make the anterior approach difficult. We analyzed relevant anatomical structures encountered during the anterior approach in the CTJ and evaluated the feasibility of previously reported surgical corridors. Methods: We retrospectively examined 49 patients who underwent neck computed tomography angiography between January 2015 and May 2020. Using the coronal images, we measured the intercarotid artery angle (ICAA), intercarotid artery distance (ICAD), shape of the brachiocephalic trunk (BCT), and position of the BCT base. We then measured the most cranial level requiring manubriotomy for the anterior approach (ML), the most caudal level accessible through the superior corridor (SC), and the most caudal level through the inferior corridor (IC) according to the surgeon's line of sight using the sagittal axis image. Results: The mean ICAA and ICAD were 50.83° ± 15.23° and 33.38 ± 12.11 mm, respectively. Notably, BCT shape was of the convex type in most cases (42.9%), followed by the straight type (36.7%). In addition, the base of BCT was most commonly located inside the body (49%). Moreover, ICAA and ICAD were significantly greater in men. Although men mostly had the BCT base inside the body (64.3%), female mostly had it on the edge of the body (47.6%). Notably, ML showed the highest frequency (16.3%) in the T1 lower and upper bodies. Furthermore, through SC and IC, it was possible to approach the T4 lower body and T6 midbody, respectively. SC showed the highest frequency (16.3%) in the T3 lower body, and IC showed the highest frequency (20.4%) in the T5 midbody. Conclusions: ICAA and ICAD were larger and higher in men. BCT was convex and located inside the body in most cases. The accessible level of ML, SC, and IC were T1, T3, and T5, respectively. For the anterior approach in the CTJ, preoperative vascular and accessible level analysis of corridors is essential to decide on the appropriate corridor and reduce complications.

Combined effects of hematopoietic progenitor cell mobilization from bone marrow by granulocyte colony stimulating factor and AMD3100 and chemotaxis into the brain using stromal cell-derived factor-1α in an Alzheimer's disease mouse model.

Transplantation of bone marrow-derived stem cells (BMSCs) has been suggested as a potential therapeutic approach to prevent neurodegenerative diseases, but it remains problematic due to issues of engraftment, potential toxicities, and other factors. An alternative strategy is pharmacological-induced recruitment of endogenous BMSCs into an injured site by systemic administration of growth factors or chemokines. Therefore, the aim of this study was to examine the effects of therapy involving granulocyte colony stimulating factor (G-CSF)/AMD3100 (CXCR4 antagonist) and stromal cell-derived factor-1α (SDF-1α) on endogenous BM-derived hematopoietic progenitor cell (BM-HPC) recruitment into the brain of an Alzheimer's disease (AD) mouse model. To mobilize BM-HPCs, G-CSF was injected intraperitoneally and boosted by AMD3100. Simultaneously, these mice received an intracerebral injection with SDF-1α to induce migration of mobilized BM-HPCs into brain. We found that the memory deficit in the AD mice was significantly improved by these treatments, but amyloid ß deposition was unchanged. Interestingly, microglial activation was increased with alternative activation of microglia to a neuroprotective phenotype. Furthermore, by generating an amyloid precursor protein/presenilin 1-green fluorescent protein (GFP) chimeric mouse, we ascertained that the GFP positive microglia identified in the brain were BM-derived. Additionally, increased hippocampal neurogenesis and improved memory was observed in mice receiving combined G-CSF/AMD3100 and SDF-1α, but not in controls or animals receiving each treatment alone. These results suggest that SDF-1α is an effective adjuvant in inducing migration into brain of the endogenous BM-HPCs, mobilized by G-CSF/AMD3100, and that the two can act synergistically to produce a therapeutic effect. This approach warrants further investigation as a potential therapeutic option for the treatment of AD patients in the future.

Associations between matrilin-1 gene polymorphisms and adolescent idiopathic scoliosis curve patterns in a Korean population.

Adolescent idiopathic scoliosis (AIS) is a complex disorder with an unclear etiology and pathogenesis. In previous studies, genome-wide linkage and genetic association analyses have been carried out to find genetic factors linked with AIS. In this study, we examined whether the susceptibility to AIS is associated with MATN1 gene polymorphisms in a Korean population, which included 166 individuals with AIS and 126 controls. We found that there were no statistically significant associations between any of the MATN1-linked allele or genotype frequencies between AIS and controls. However, statistically significant associations were found at single nucleotide polymorphism (SNP) rs1065755 when comparing the curve patterns of AIS with the controls. The A allele of SNP rs1065755 was associated with a higher risk of AIS than the allele G in the genotype-phenotype (curve pattern) analysis (P = 0.029). In addition, the frequency of the A allele of SNP rs1065755 in AIS with double major curves was higher than in controls (P = 0.021, ORs = 2.56 within 95% CI = 1.12-5.83). Additionally, among the predicted common haplotypes, the frequency of the haplotype GATT (31.3%) in AIS with double major curves was higher than in controls (15.2%) (P = 0.024, ORs = 2.54 within 95% CI = 1.11-5.84). We conclude that the A allele of SNP rs1065755 in the MATN1 gene is associated with AIS.

Bicortical Laminar Screws for Posterior Fixation of Subaxial Cervical Spine: A Radiologic Analysis With Computed Tomography Images.

STUDY DESIGN: Retrospective radiological analysis. OBJECTIVES: Translaminar screw (TLS) placement is one of the fixation techniques in the subaxial cervical spine. However, it can be difficult to use in small diameter of the lamina. This study proposed a novel bicortical laminar screw (BLS) and analyzed the related parameters using computed tomography (CT). METHODS: Cervical CT images taken at our institution from January 2013 to March 2017 were used for measurement. On the axial images, the maximum screw length (MSL) and trajectory angle (TA) of BLS and TLS were measured, together with the distance from the midline (DM) to the BLS entry point and the lamina width (LW). On the parasagittal images, the height of the lamina (LH) was measured. RESULTS: MSL of BLS and TLS were 21.00 and 20.97 mm, 19.02 and 20.91 mm, 18.45 and 21.01 mm, and 20.00 and 21.01 mm in C3, C4, C5, and C6, respectively. TA of the BLS and TLS were 21.24° and 34.90°, 19.05° and 34.22°, 18.65° and 33.61°, and 18.30° and 34.51° at C3, C4, C5, and C6, respectively. DM were 6.44, 5.77, 5.68, and 6.03 at C3, C4, C5, and C6, respectively. LW and LH were 3.52 and 12.44 mm, 2.87 and 12.49 mm, 2.76 and 12.42 mm, and 3.18 and 13.30 mm at C3, C4, C5, and C6, respectively. CONCLUSION: We suggest that BLS fixation is a feasible alternative option for posterior fixation to the lamina of the subaxial cervical spine. It may be especially useful when pedicle screw, lateral mass screw, and TLS are not appropriate.

Pain Relief After Selective Nerve Root Block as a Predictor of Postoperative Functional Outcome in Patients with Degenerative Lumbar Spinal Stenosis Patients Undergoing Decompressive Surgery.

STUDY DESIGN: Retrospective study of data collected prospectively. OBJECTIVE: To investigate changes in the degree of lower leg radiating pain (LLRP) after selective nerve root block (SNRB) and to evaluate associations of this change with postoperative improvements in symptom severity, functional outcomes, and quality of life. SUMMARY OF BACKGROUND DATA: SNRB is routinely performed as an initial treatment for lumbar foraminal or lateral recess stenosis with LLRP. The degree of improvement after SNRB has been suggested to predict the improvement in postoperative pain and functional outcomes. However, there have been no studies on the predictive value of this parameter. METHODS: We enrolled 60 patients who underwent SNRB followed by decompressive surgery. They were divided into three groups. The degree of improvement was evaluated as a percentage of the pre-injection values. Functional outcomes of the spine were assessed using the Oswestry Disability Index (ODI) and Roland-Morris Disability Questionnaire (RMDQ). Quality of life was assessed using the 36-item Short Form Survey (SF-36) physical component score (PCS) and mental component score (MCS). The degree of LLRP was measured preoperatively and at 6, 12, and 24 months after surgery. These functional outcomes were evaluated preoperatively and at 12 and 24 months after surgery. RESULTS: The improvement in LLRP in the short term (6 hours after SNRB) was found to be statistically significantly associated with the improvement in LLRP at 12 months after SNRB (P = 0.044, correlation coefficient = 0.261). No relationship between pain improvement after SNRB and functional outcome was identified. CONCLUSION: The degree of improvement in symptoms 6 hours after SNRB can predict the degree of improvement in LLRP at 12 months after surgery. However, symptomatic improvement after SNRB does not predict postoperative functional outcome or quality of life.Level of Evidence: 4.

Bone marrow-derived mesenchymal stem cells prevent the loss of Niemann-Pick type C mouse Purkinje neurons by correcting sphingolipid metabolism and increasing sphingosine-1-phosphate.

Niemann-Pick type C (NP-C) disease exhibits neuronal sphingolipid storage and cerebellar Purkinje neuron (PN) loss. Although it is clear that PNs are compromised in this disorder, it remains to be defined how neuronal lipid storage causes the PN loss. Our previous studies have shown that bone marrow-derived mesenchymal stem cells (BM-MSCs) transplantation prevent PN loss in NP-C mice. The aim of the present study was therefore to examine the neuroprotective mechanism of BM-MSCs on PNs. We found that NP-C PNs exhibit abnormal sphingolipid metabolism and defective lysosomal calcium store compared to wild-type mice PNs. BM-MSCs promote the survival of NP-C PNs by correction of the altered calcium homeostasis, restoration of the sphingolipid imbalance, as evidenced by increased sphingosine-1-phosphate levels and decreased sphingosine, and ultimately, inhibition of apoptosis pathways. These effects suggest that BM-MSCs modulate sphingolipid metabolism of endogenous NP-C PNs, resulting in their survival and improved clinical outcome in mice.