Creation of a planned or central-clefted puncture combined with a second puncture during vertebroplasty to treat osteoporotic vertebral compression fractures with large clefts.

BACKGROUND: Cemented vertebrae frequently re-fracture after vertebroplasty to treat osteoporotic vertebral compression fractures (OVCFs) with large clefts. We compared the efficacy of planned and central-clefted puncture, both followed by a second puncture, as treatments for OVCFs with large clefts. METHODS: We retrospectively studied 38 patients. 18 of whom underwent planned puncture (group A) and 20 central-clefted puncture (group B). A second puncture was performed when the initially injected cement was restricted to the cleft. We recorded a visual analog scale (VAS) pain scores, vertebral kyphotic angles (KAs), and compression ratios (CRs) preoperatively and at 2 days and 6 months postoperatively. We recorded the cement dispersion patterns and complications. RESULTS: Second punctures succeeded in 15/18 and 7/20 patients of groups A and B, respectively. At 2 days postoperatively, the VAS score, KA, and CR were significantly better than the preoperative values (P < 0.01); no significant difference was found between the two groups (P > 0.05). At the 6-month follow-up, all scores were poorer than at 2 days postoperatively (all P < 0.05), significantly more so in group B than group A (P < 0.05). Significant differences in terms of the cement dispersion patterns, and the cemented vertebral re-fracture and cement leakage rates, were observed between the two groups (all P < 0.05). CONCLUSION: The two-puncture techniques were initially effective when treating large-clefted OVCFs. However, compared to the central-clefted puncture, the planned puncture improved the success rate of the second puncture, allowed better cement dispersion, and reduced the incidence of vertebral re-fracture during follow-up.

[Clinical outcomes of spinal endoscopic surgery for tiny lumbar disc herniation with severe radiating pain of lower limb].

OBJECTIVE: To study the clinical characteristics of the patients with tiny lumbar disc herniation and severe symptoms(tLDHSS) and the therapeutic effects of percutaneous endoscopic lumbar discectomy(PELD). METHODS: From January 2014 to February 2019, 34 patients with tLDHSS were reviewed retrospectively, including 20 males and 14 females, aged from 31 to 73 (48.8±10.1) years, with a follow up duration ranged from 8 to 48 (21.8±10.3) months. The clinical manifestations, imaging and surgical data were analyzed. The visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores were analyzed before operation, 1 month after operation and at the latest follow-up. The preoperative and postoperativescores were compared. At the latest follow up, the Macnab system was used to evaluate the effects of the operation. RESULTS: The main symptom of 34 cases was severe radiation pain on one side of lower limbs. The duration of preoperative symptoms ranged from 0.33 to 84 months. The disc herniation was found in 7 cases of L4, 5 and 27 cases of L5S1. According to the MSU division of lumbar disc herniation, 31 cases were located in area B. In all cases, it was confirmed that the protruding nucleus compressed the nerve root, and in 26 cases, the nerve root was obviously inflamed. The operation time ranged from 30 to 80 min, with a mean time of (43.5±9.5) min. The preoperative VAS score was 8.1±1.3 and ODI score was 31.8±6.7. And the VAS score was 1.1± 0.3, 0.7±0.4 on the first month after operation and the latest follow up, respectively. The ODI score was 5.3±2.1 and 0 to 10 (with a median score of 2) on the first month after operation and the latest follow-up respectively. The postoperative VAS and ODI scores were improved compared with preoperative scores.At the latest follow up, 28 cases got an excellent result and 6 cases good according to Macnab evaluation system. During the follow-up period, only one patient had recurrent disc herniation. CONCLUSION: The main symptom of patients with tLDHSS is severe radiation pain on one side of lower limb. It manifests as sudden onset and shorter course of disease. Severe local inflammation was induced by local compression of the protruding nucleus pulposus on the nerve root out of the dura. For this kind of patients, thin layer CT scan has an important diagnostic value. In the treatment of this kind of patients, the symptoms are relieved rapidly, the curative effect is definite and the recurrence rate is low.

[Application of percutaneous vertebroplasty with the second injection for poor dispersion bone cement of Kümmel disease].

OBJECTIVE: To investigate clinical effect of percutaneous vertebroplasty with second injection for poor dispersion bone cement of Kümmel disease. METHODS: Eighty-eight patients with Kümmel disease were treated with vertebroplasty from February 2014 to December 2017, and 16 patients were found cement dispersion unsatisfactory during initial cement injection and were undertaken second cement injection during operation. Among patients, there were 1 male and 15 females aged from 63 to 82 years old with an average age of 72.7 years old. Distribution of fractured vertebrae were followed: 1 patient was on T10, 1 patient was on T11, 3 patients were on T12, 8 patients were on L1, 1 patient was on L2, and 2 patients were on L3. VAS and ODI score were compared before operation, 2 days after operation and the latest following-up, anterior vertebral height and local kyphosis angle of fractured vertebrae with intravertebral cleft were also observed. Postoperative complication was recorded. RESULTS: All patients were followed up from 5 to 22 months with average of 14.1 months. ODI score before operation, 2 days after operation and the latest following-up were 72.3±12.1, 56.8±5.0 and 12.1±5.3 respectively; VAS score before operation, 2 days after operation and the latest following-up were 7.8±0.6, 3.0±0.4 and 2.4±0.7, respectively; ODI score at 2 days was improved compared with before operation, while ODI and VAS score at the latest following-up was improved than that of 2 days after operation. Vertebral anterior compression rate and Cobb angle of the fractured vertebrae with intravertebral cleft were respectively corrected from (37.8±5.4)% and (15.1±2.0)°preoperative, to (4.7±1.4)% and (4.4±2.2)° at 2 days after operation, (4.9±1.5)% and (4.8±2.4)° at the latest following-up, there was significant difference between before operation and 2 days after operation, while there was no difference between 2 days after operation and the latest following-up. Three patients occurred cement leakage without pulmonary embolism and neurological impairment. Four patients occurred adjacent vertebrae fracture. There was no incidence of recollapsed vertebrae during follow-up period. CONCLUSIONS: Percutaneous vertebroplasty for Kümmel disease could receive satisfactory clinical results when cement dispersion was inadequate during initial cement injection by the second injection, and effectively prevent occurrence of vertebral re-collapse.

[Effect of the proximal level on post-laminoplasty loss of lordosis].

OBJECTIVE: To analyze the effect whether or not retaining muscle ligament complex of C2 attachment on cervical spine kyphotic deformity after single open-door laminoplasty. METHODS: A total 40 patients with cervical spondylotic myelopathy underwent single open-door laminoplasty from February 2011 to June 2014 were retrospectively analyzed. Of them, single open-door for C3-C6 was 40 cases (group A), including 28 males and 12 females, with an average age of (68.4±9.3) years old;and single open-door for C4-C6 plus C3 laminectomy decompression (in order to protect the muscle ligament complex of C2 attachment) was 40 cases (group B), including 26 males and 14 females, with an average age of (66.8±8.4) years old. Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS), Cobb angle of sagittal plane from C2-C7, cervical range of motion were used to evaluate effects before operation and at the latest follow-up. RESULTS: All the patients were followed up from 24 to 31 months with an average of(26.5±3.4) months. There was no significant differences in VAS, JOA scores and cervical range of motion before surgery between two groups (P>0.05) and all above items were significantly improved at the latest follow-up (P<0.05), but there was no significant difference between two groups(P>0.05). There was no significant difference in cervical Cobb angle before surgery between two groups(P>0.05), and postoperative Cobb angle had obviously improved in two groups(P<0.05), but the improvement of group B was better than that of group A. CONCLUSIONS: Starting the laminoplasy on C4 level and retainning the muscle ligament complex of C2 attachment can obviouly decrease cervical spine syphotic deformity.

[Application of Gemstone Spectrum Imaging for anterior spinal artery in patients with cervical spinal injury].

OBJECTIVE: To discuss the value of Gemstone Spectrum Imaging (GSI) CT anterior spinal artery angiography in the patients with cervical spinal cord injury, and to evaluate the correlation between the change of the blood flow of the anterior spinal artery and the postoperative recovery of nerve function. METHODS: From January 2014 to June 2016, thirty patients who underwent cervical open door laminoplasty for spinal cord injury were retrospective analyzed and included 21 males and 9 females with an average age of (46.4±9.7) years old ranging from 33 to 59 years. Within 2 weeks after injury, open door laminoplasty was performed through cervical posterior approach. Among them, there were 8 cases of 3 segments of open door decompression, 18 cases of 4 segments, 4 cases of 5 segments. GSI CT were performed at 3 days before operation and 5 days after operation. The anterior spinal artery was reconstructed and evaluated the improvement of blood flow after operation. The cervical JOA score was calculated at 1 day before operation, 5 days after operation and 1, 6 and 12 months after operation, and the JOA score improvement rate of the corresponding follow-up points was calculated. RESULTS: All patients were followed up for 12 to 30 months with an average of (17.4±7.6) months. The iodine content ratio (ASA/VA) of the anterior spinal artery before and after operation was 0.75±0.20 and 0.89±0.02 respectively, the postoperative improvement was significantly higher than that before operation(P<0.01). The average ASA/VA improvement rate was(21.05±12.45)% after operation. There was a positive linear correlation between the improvement of blood flow and the improvement of JOA score at 1, 6 and 12 months after operation. CONCLUSIONS: GSI CT anterior spinal artery angiography is safe and feasible, the imaging is satisfactory, it can quantitatively evaluated the blood flow of the anterior spinal artery. There was a positive linear correlation between the improvement of blood flow in anterior spinal artery and the recovery of neurological function. Early postoperative improvement of blood flow in the anterior spinal artery can be used as a reference index for predicting the recovery of neurological function in patients.

AMP-activated protein kinase-dependent induction of autophagy by erythropoietin protects against spinal cord injury in rats.

AIMS: Autophagy has been regarded as a promising therapeutic target for spinal cord injury (SCI). Erythropoietin (EPO) has been demonstrated to exhibit neuroprotective effects in the central nervous system (CNS); however, the molecular mechanisms of its protection against SCI remain unknown. This study aims to investigate whether the neuroprotective effects of EPO on SCI are mediated by autophagy via AMP-activated protein kinase (AMPK) signaling pathways. METHODS: Functional assessment and Nissl staining were used to investigate the effects of EPO on SCI. Expressions of proteins were detected by Western blot and immunohistochemistry. RESULTS: Treatment with EPO significantly reduced the loss of motor neurons and improved the functional recovery following SCI. Erythropoietin significantly enhanced the SCI-induced autophagy through activating AMPK and inactivating mTOR signaling. The inhibitor of AMPK, compound C, could block the EPO-induced autophagy and beneficial action on SCI, whereas the activator of AMPK, metformin, could mimic the effects of EPO. In the in vitro studies, EPO enhanced the hypoxia-induced autophagy in an AMPK-dependent manner. CONCLUSIONS: The AMPK-dependent induction of autophagy contributes to the neuroprotection of EPO on SCI.

Is the Cervical Anterior Spinal Artery Compromised in Cervical Spondylotic Myelopathy Patients? Dual-Energy Computed Tomography Analysis of Cervical Anterior Spinal Artery.

OBJECTIVE: Cervical myelopathy is a common, acquired cause of spinal cord dysfunction in older patients. It is postulated that a hypoxic or ischemic environment secondary to chronic spinal cord compression plays an important role in the pathogenesis of myelopathy. This study aims to use dual-energy computed tomography (DECT) to assess the altered blood flow to the spinal cord in patients with cervical spondylotic myelopathy (CSM). To our knowledge, this study is the first to use DECT in identifying comprised anterior spinal artery blood flow in patients with CSM. METHODS: Fifty patients with single disc level CSM and 10 volunteers without CSM underwent DECT of the cervical spine to analyze and compare the ASA. The neurologic status of each patient was evaluated preoperatively and postoperatively at 5 days, 1 month, and 6 months using the Japanese Orthopedic Association (JOA) score. All the patients with CSM underwent single-level anterior cervical discectomy and fusion, and at postoperative day 5, each patient underwent repeated DECT. The anterior spinal artery before and after surgery was compared in patients with CSM. The blood flow in terms of iodine content at a specific region of interest was measured in the axial CT of the volunteers group and in the preoperative and postoperative axial CT of patients with CSM. Correlations between change in blood flow and clinical improvement at each follow-up point were analyzed statistically. RESULTS: Iodine content (100 mg/mL) was 14.2800 ± 1.89527 at the C3/C4 disc level, 14.8280 ± 1.83820 at the C4/C5 disc level, and 15.5000 ± 2.41048 at the C5/C6 level. In patients with CSM, the preoperative iodine content (100 mg/mL) measured was 10.2621 ± 2.37396 in C3/C4 disc-level compression, 12.1438 ± 1.63447 in C4/C5 disc-level compression, and 14.0620 ± 2.44390 in C5/C6 disc-level compression. Postoperative iodine content (100 mg/mL) measurement changed to 13.78 ± 2.77 for the C3/C4 disc level, 14.16 ± 1.90 for the C4/C5 disc level, and 15.14 ± 2.62 for the C5/C6 disc level. The JOA score was 13.650 preoperatively, 14.010 at 5 days postoperatively, 14.630 at 1 month postoperatively, and 15.000 at 6 months postoperatively. The 1- and 6-month correlation ratios between the JOA and change in blood flow were statistically significant, with an r value of 0.746 (P < 0.05) and 0.760 (P < 0.05), respectively. CONCLUSIONS: This study provided evidence for the benefit of DECT as a radiographic tool for identifying the compromised cervical anterior spinal artery in patients with CSM. We believe that DECT is the one of the best radiographic tools available to provide an objective screening tool to detect compromised blood flow in patients with CSM.

Polarized Distribution of Active Myosin II Regulates Directional Migration of Cultured Olfactory Ensheathing Cells.

Migration of olfactory ensheathing cells (OECs) is critical for development of olfactory system and essential for neural regeneration after OEC transplantation into nerve injury site. However, the molecular mechanisms underlying the regulation of directional migration of OECs remain unclear. In this study, we found that in migrating OECs, phosphorylated myosin light chain (p-MLC, active myosin II) displayed a polarized distribution, with the leading front exhibiting higher than soma and trailing process. Over-expression of GFP-MLC significantly reduced OEC migration. Moreover, decreasing this front-to-rear difference of myosin II activity by the frontal application of a ML-7 (myosin II inhibitors) gradient induced the collapse of leading front and reversed soma translocation of OECs, whereas, increasing this front-to-rear difference of myosin II activity by the rear application of a ML-7 or BDM gradient or the frontal application of a Caly (myosin II activator) gradient accelerated the soma translocation of OECs. Finally, myosin II as a downstream signaling of repulsive factor Slit-2 mediated the reversal of soma translocation induced by Slit-2. Taken together, these results suggest that the polarized distribution of active myosin II regulates the directional migration of OECs during spontaneous migration or upon to extracellular stimulation such as Slit-2.

[Analysis of complications of percutaneous endoscopic lumbar discectomy].

OBJECTIVE: To analyze the complications of lumbar intervertebral disc herniation treated with percutaneous endoscopic lumbar discectomy(PELD), and discuss how to avoid these complications. METHODS: The data of 132 patients with lumbar intervertebral disc herniation underwent PELD from October 2013 and June 2015 were retrospectively analyzed, including 85 males and 47 females with an average age of 42.9 years old. There were 6 cases of L3,4, 68 of L4,5 and 58 of L5S1. The incidences of intraoperative and postoperative complications were analyzed. RESULTS: There was spinal dura mater injury in 1 patient, but no cerebrospinal fluid leakage and nerve function deficit was found, the muscle strength did not decrease postoperatively and the incision healed well. Two patients converted to open surgery ultimately because of stenosis of the intervertebral foramen and adhesion between nucleus pulposus and spinal dura mater; two patients complicated with early recurrence(in 3 months);nucleus pulposus residue developed in 3 patients; all of them were treated by open surgery and got satisfactory results. One patient with heart disease history complicated with supraventricular tachycardia after surgery and 2 patients with the increased cerebrospinal fluid pressure during surgery. CONCLUSIONS: PELD have a steep learning curve, and the technology is a safe and effective method in treating lumbar disc herniation, but the beginners must have enough open surgery experience, and to grasp indications strictly.

[Unilateral Wiltse intermuscular approach and contralateral decompression for the treatment of thoracolumbar burst fracture].

OBJECTIVE: To compare the clinical effects and multifidus muscle injury of different approaches, including unilateral Wiltse intermuscular approach and intramuscular approach combined with contralateral decompression, in treating thoracolumbar burst fracture. METHODS: Forty-three patients with thoracolumbar burst fracture were enrolled in the study from January 2010 to December 2014, including 29 males and 14 females with an average age of 42.3 years old(ranged from 21 to 64 years old). The patients were treated with posterior pedicle screw fixation and unilateral decompression and were divided into Wiltse intermuscular approach group (group A) and intramuscular approach group (group B) according to surgical approach. Operation time and intraoperative bleeding were recorded for all patients; visual analogue scale(VAS) was compared 1 d preoperatively, 1 week, 12 months postoperatively between two groups; preoperation and 12 months postoperatively, the fractured vertebral canal and two-sides multifidus muscle of the same section were observed and compared by CT measure between two groups. RESULTS: All the patients were follow-up for 14 to 21 months with an average of 16.3 months. Partial wound non-healing occurred in 3 patients and the wound ultimately healing after debridgement suture and change dressings. No screw breakage was found. There was significant difference in operation and intraoperative bleeding operation between two groups (P<0.05), while there was no significant difference in VAS score of 1 d preoperatively, 1 week, 12 months postoperatively between two groups(P>0.05). As for CT measurement results, postoperative vertebral canal narrow ratio was significant decreased in all patients(P<0.05), while perioperative changes of the two-sides multifidus muscle cross section area and density were significant in group A (P<0.05), but there was no significant difference in group B (P>0.05). Neurologic status of all patients got recovery at final follow-up. CONCLUSIONS: The method of unilateral Wiltse intermuscular approach combined with contralateral decompression for the treatment of thoracolumbar burst fracture has good clinical effects, also it is less invasive and less damage to multifidus muscle compared with intramuscular approach.

Application of de-neurofilm in treatment of patellar arthritis with knee / 中国内镜杂志

Objective To investigate the curative effect of knee arthroplasty combined with denervation technique on knee patellofemoral arthropathy. Methods 60 patients with patellofemoral arthritis were selected from September 2009 to September 2015 for the study. All the patients were divided into observation group and control group by random number table. The patients in the control group were treated with arthroscopic treatment, and the patients in observation group were treated with arthroscopic cleaning and patellar biotherapy. The WOMAC score, the Lysholm score, and the Kujala score were compared between the two groups before and 3 months after surgery. Results There was no significant difference between the preoperative observation group and the control group (P > 0.05). The scores of WOMAC score, Lysholm score and Kujala score were higher in the observation group and the control group than those before the control group (P < 0.05 ). There were 2 cases of infection and 1 case of vascular nerve injury in 30 cases of postoperative 3 m observation group. One case of infection and 1 case of joint activity were restricted in 30 cases of control group. There was no significant difference in postoperative adverse reaction between the two groups (P > 0.05). Conclusions Given patellofemoral arthritis knee arthroplasty arthroscopy combined with patellar percutaneous nerve treatment can relieve pain, improve patellofemoral function and clinical efficacy, can be further popularized and used in clinical practice.

Application of de-neurofilm in treatment of patellar arthritis with knee / 中国内镜杂志

Objective To investigate the curative effect of knee arthroplasty combined with denervation technique on knee patellofemoral arthropathy. Methods 60 patients with patellofemoral arthritis were selected from September 2009 to September 2015 for the study. All the patients were divided into observation group and control group by random number table. The patients in the control group were treated with arthroscopic treatment, and the patients in observation group were treated with arthroscopic cleaning and patellar biotherapy. The WOMAC score, the Lysholm score, and the Kujala score were compared between the two groups before and 3 months after surgery. Results There was no significant difference between the preoperative observation group and the control group (P > 0.05). The scores of WOMAC score, Lysholm score and Kujala score were higher in the observation group and the control group than those before the control group (P < 0.05 ). There were 2 cases of infection and 1 case of vascular nerve injury in 30 cases of postoperative 3 m observation group. One case of infection and 1 case of joint activity were restricted in 30 cases of control group. There was no significant difference in postoperative adverse reaction between the two groups (P > 0.05). Conclusions Given patellofemoral arthritis knee arthroplasty arthroscopy combined with patellar percutaneous nerve treatment can relieve pain, improve patellofemoral function and clinical efficacy, can be further popularized and used in clinical practice.

Brain-derived Neurotrophic Factor Promotes the Migration of Olfactory Ensheathing Cells Through TRPC Channels.

Olfactory ensheathing cells (OECs) are a unique type of glial cells with axonal growth-promoting properties in the olfactory system. Organized migration of OECs is essential for neural regeneration and olfactory development. However, the molecular mechanism of OEC migration remains unclear. In the present study, we examined the effects of brain-derived neurotrophic factor (BDNF) on OEC migration. Initially, the "scratch" migration assay, the inverted coverslip and Boyden chamber migration assays showed that BDNF could promote the migration of primary cultured OECs. Furthermore, BDNF gradient attracted the migration of OECs in single-cell migration assays. Mechanistically, TrkB receptor expressed in OECs mediated BDNF-induced OEC migration, and BDNF triggered calcium signals in OECs. Finally, transient receptor potential cation channels (TRPCs) highly expressed in OECs were responsible for BDNF-induced calcium signals, and required for BDNF-induced OEC migration. Taken together, these results demonstrate that BDNF promotes the migration of cultured OECs and an unexpected finding is that TRPCs are required for BDNF-induced OEC migration. GLIA 2016;64:2154-2165.

Inhibition of Autophagy by Estradiol Promotes Locomotor Recovery after Spinal Cord Injury in Rats.

17ß-estradiol (E2) has been shown to have neuroprotective effects in different central nervous system diseases. The mechanisms underlying estrogen neuroprotection in spinal cord injury (SCI) remain unclear. Previous studies have shown that autophagy plays a crucial role in the course of nerve injury. In this study, we showed that E2 treatment improved the restoration of locomotor function and decreased the loss of motor neurons in SCI rats. Real-time PCR and western blot analysis revealed that the protective function of E2 was related to the suppression of LC3II and beclin-1 expression. Immunohistochemical study further confirmed that the immunoreactivity of LC3 in the motor neurons was down-regulated when treated with E2. In vitro studies demonstrated similar results that E2 pretreatment decreased the autophagic activity induced by rapamycin (autophagy sensitizer) and increased viability in a PC12 cell model. These results indicated that the neuroprotective effects of E2 in SCI are partly related to the suppression of excessive autophagy.

[Cervical single open door laminoplasty with lateral mass screw fixation for the treatment of cervical spondylotic myelopathy with cervical instability].

OBJECTIVE: To evaluate the outcomes of single open door laminoplasty with lateral mass screw fixation in treating cervical spondylotic myelopathy (CSM) with cervical instability. METHODS: From March 2010 to October 2012, 25 patients with spondylotic myelopathy and cervical instability underwent single open door laminoplasty with lateral mass screw fixation. There were 18 males and 7 females, aged from 57 to 68 years with the mean of 57 years. Japanese Orthopaedic Association (JOA) scores were used to evaluate clinical effects before operation and final follow up. Radiographical measures were made in change of Cobb angle by sagittal plane from C2 to C7, and cervical range of motion. RESULTS: All the patients were followed up from 18 to 36 months with an average of 25.6 months. Cerebrospinal fluid leakage occurred in 1 case, incision fat necrosis in 1 case, C5 nerve root palsy in 4 cases. JOA scores was improved from preoperative 5.2±2.1 to 11.3±2.4 final follow up. Cobb angle was changed from preoperative (6.5±3.4)° to (13.2±4.9)° final follow up. Cervical range of motion was changed from preoperative (30.4±9.2)° to (26.5±8.4)° final follow up. CONCLUSIONS: As an effective treatment to CSM with cervical instability, single open door laminoplasty with lateral mass screw fixation has the advantage of extensive application scope, safety and steady, but the incidence rate of complication must be reduced.

[Outcomes and related factors of C5 nerve root palsy after cervical posterior single open-door laminoplasty].

OBJECTIVE: To analyze the clinical outcomes and related factors of C5 palsy following cervical laminectomy in treating multi-segments cervical spondylotic myelopathy. METHODS: From January 2010 to June 2014, 80 patients with spondylotic myelopathy underwent C3-C6 open-door laminoplasty(group A) and 80 patients C4-C6 open-door laminoplasty (group B). The mean age was (68.4±9.2) years (44 males and 36 females) in group A and the mean age was (66.8±8.9) years (48 males and 32 females) in group B. Japanese Orthopaedic Association(JOA) score, Visual Analogue Score, incidence of C5 palsy, time of onset, grade of muscle weakness, other accompanying cervical nerve root palsies, recovery time were used to evaluate clinical effects before operation and at last follow-up. Radiographically, changes of Cobb angle of sagittal plane from C2-C7, cervical range of motion, minimal spinal cord diameter on MRI were analyzed before operation and at last follow-up. RESULTS: All the patients were followed up from 6 to 15 months with an average of (12.4±3.2) months. No obvious differences were observed between change of VAS of cervical and upper limb, JOA, Cobb angle, cervical range of motion, minimal spinal cord diameter on MRI. C5 nerve root palsy occurred in 7 cases (8.75%) in group A, including 4 cases of upper limb pain, 3 cases of upper limb pain, and 2 cases of residual upper limb pain and sensory loss at the last follow-up. C5 nerve root palsy occurred in 5 cases (7.5%) in group B, 3 cases of upper limb pain, 2 cases of upper limb sensory loss, and all patients recovered normal radiation pain and sensory loss at the last follow-up. There was no significant difference in the incidence of C5 nerve root palsy between the two groups. C5 nerve root palsy, deltoid muscle, accompanied by neurological symptoms, recovery time were(2.3±1.0) N, 30 cases (37.5%), (11.4±1.0) weeks in group A, (2.8±0.8) N, 23 cases (28.8%), (8.2±0.8) weeks in group B, there was no significant difference on deltoid muscle decreased between the two groups, accompanied by neurological symptoms and the recovery time in group A was worse than the group B. CONCLUSIONS: Comparison of the two kinds of operation, the probability of postoperative C5 nerve root palsy was equal, but the C5 nerve root palsy in patients with C4-C6 open-door laminoplasty showed lighter symptom and faster recovery.

[Clinical application of unilateral axis translaminar screws in upper cervical instability with vertebral artery variations].

OBJECTIVE: To investigate the clinical outcomes of the posterior C1,2 screw-rod combined with C2 unilateral translaminar screw and contralateral pedicle screw fixation and autogenous bicortical iliac crest graft fusion in treating upper cervical instability with vertebral artery variations. METHODS: From June 2008 to December 2012, the clinical data of 12 patients with upper cervical instability underwent C1 lateral mass screws-C2 unilateral laminar and contralateral pedicle screws fixation combined with autogenous bicortical iliac crest graft fusion were analyzed retrospectively. There were 8 males and 4 females with a mean age of 47.5 years (ranged, 16 to 77 years). Patients suffered from occipitocervical activity limitation of motion with pain or not, VAS was 0-7 points with an average of (3.50 +/- 2.71) points. Unilateral vertebral artery hypoplasia was demonstrated by vertebral arteriography (VAG) or CTA in all patients. Cervical X-ray and CT scans were done within 7 days after surgery in order to confirm internal fixation position. Internal fixation loosening and breakage, reduction losing, bone fusion ratio were observed during follow-up. RESULTS: No nerves and vertebral artery injuries occurred during operation. Cervical pain obviously decreased and VAS was (0.92 +/- 0.90) points. Cervical alignment of 12 patients had well-recovered by X-ray while Atlantoaxial ventral lamina cortex of 1 case was encroached by CT scan without neurological symptom. All patients were followed up for 6 months to 3 years, no internal fixation loosening and breakage, reduction losing were found. All patients obtained bone fusion in 6-12 months after operation. CONCLUSION: Posterior C1 lateral mass screws-C2 unilateral laminar and contralateral pedicle screws fixation combined with autogenous bicortical iliac crest graft fusion can achieve biomechanical stability and raise the successful rate of bone fusion, while avoiding the risk of vertebral artery injury and overcoming the insufficient of bone fusion during bilateral laminar screws placement as well. Posterior C1 lateral mass screws fixation is a safe and effective additional method in treating upper cervical instability with vertebral artery variations.

Repulsive migration of Schwann cells induced by Slit-2 through Ca2+-dependent RhoA-myosin signaling.

Schwann cells migrate along axons before initiating myelination during development and their migration facilitates peripheral nerve regeneration after injury. Axon guidance molecule Slit-2 is highly expressed during peripheral development and nerve regeneration; however, whether Slit-2 regulates the migration of Schwann cells remains a mystery. Here we show that Slit-2 receptor Robo-1 and Robo-2 were highly expressed in Schwann cells in vitro and in vivo. Using three distinct migration assays, we found that Slit-2 repelled the migration of cultured Schwann cells. Furthermore, frontal application of a Slit-2 gradient to migrating Schwann cells first caused the collapse of leading front, and then reversed soma translocation of Schwann cells. The repulsive effects of Slit-2 on Schwann cell migration depended on a Ca(2+) signaling release from internal stores. Interestingly, in response to Slit-2 stimulation, the collapse of leading front required the loss of F-actin and focal adhesion, whereas the subsequent reversal of soma translocation depended on RhoA-Rock-Myosin signaling pathways. Taken together, we demonstrate that Slit-2 repels the migration of cultured Schwann cells through RhoA-Myosin signaling pathways in a Ca(2+)-dependent manner.

Intrinsic migratory properties of cultured Schwann cells based on single-cell migration assay.

The migration of Schwann cells is critical for development of peripheral nervous system and is essential for regeneration and remyelination after nerve injury. Although several factors have been identified to regulate Schwann cell migration, intrinsic migratory properties of Schwann cells remain elusive. In this study, based on time-lapse imaging of single isolated Schwann cells, we examined the intrinsic migratory properties of Schwann cells and the molecular cytoskeletal machinery of soma translocation during migration. We found that cultured Schwann cells displayed three motile phenotypes, which could transform into each other spontaneously during their migration. Local disruption of F-actin polymerization at leading front by a Cytochalasin D or Latrunculin A gradient induced collapse of leading front, and then inhibited soma translocation. Moreover, in migrating Schwann cells, myosin II activity displayed a polarized distribution, with the leading process exhibiting higher expression than the soma and trailing process. Decreasing this front-to-rear difference of myosin II activity by frontal application of a ML-7 or BDM (myosin II inhibitors) gradient induced the collapse of leading front and reversed soma translocation, whereas, increasing this front-to-rear difference of myosin II activity by rear application of a ML-7 or BDM gradient or frontal application of a Caly (myosin II activator) gradient accelerated soma translocation. Taken together, these results suggest that during migration, Schwann cells display malleable motile phenotypes and the extension of leading front dependent on F-actin polymerization pulls soma forward translocation mediated by myosin II activity.

[Clinical screening of patients with cerebral arteriosclerosis combined with vertebral artery abnormalies].

OBJECTIVE: To explore the clinical screening and value of vertebral artery ultrasound, Transcranial doppler (TCD), Magnetic resonance angiography (MRA) and Computed tomography angiography (CTA) in the diagnosis of cerebral arteriosclerosis combined with vertebral artery abnormalies according to vertebral artery digital subtraction angiography (DSA). METHODS: From January 2006 to September 2010, 186 patients with cerebral arteriosclerosis were retrospectively analyzed. Among the patients, 133 cases were males and 53 cases were females,ranged from 30 to 84 years (with a mean of 63.8 years). All the patients were estimated by DSA; 172 cases were estimated vertebral artery ultrasound and TCD; 53 cases were estimated by MRA; 25 cases were estimated by CTA. The positive results by DSA were seen as case group, while the negative results were seen as control group. The sensitivity, specificity and concordance rate among four groups were calculated. RESULTS: The abnormality rate of vertebral artery with DSA, vertebral artery ultrasound, TCD, MRA and CTA separately was 50.00% (93/186), 30.81% (53/172), 49.42% (85/172),15.10% (8/53) and 40.00% (10/25). According to DSA standard, the sensitivity of vertebral artery ultrasound in diagnosing was 50.57%, the specificity was 89.41%, and concordance rate was 69.77%; while the sensitivity of TCD was 68.48%, the specificity was 72.50%, and concordance rate was 70.35%; the sensitivity of MRA was 21.43%, specificity was 92.00%, and concordance rate was 54.72%; the sensitivity of CTA was 63.64%,the specificity was 78.57%, and concordance rate was 72.00%. CONCLUSION: The reasonable and combined application of vertebral artery ultrasound, TCD, MRA and CTA is helpful for diagnosing cerebral arteriosclerosis combined with vertebral artery abnormalies. For the patients with cerebrovascular disease, cervical massage technique should be paid highly attention, which may cause vertebral artery injury and other complications.