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BACKGROUND Spinal adhesive arachnoid pathology is a rare cause of myelopathy. Because of rarity and variability, mechanisms of myelopathy are unknown. The authors retrospectively analyzed patients to understand pathophysiology and provide implications for surgical treatment. OBSERVATIONS Nineteen consecutive patients were studied. Thirteen patients had a secondary pathology due to etiological disorders such as spinal surgery or hemorrhagic events. They received arachnoid lysis (4 patients), syringo-subarachnoid (S-S) shunt (8 patients) with or without lysis, or anterior decompression. Three of them developed motor deterioration after lysis, and 6 patients needed further 8 surgeries. Another 6 patients had idiopathic pathology showing dorsal arachnoid cyst formation at the thoracic level that was surgically resected. With mean follow-up of 44.3 months, only 4 patients with the secondary pathology showed improved neurological grade, whereas all patients with idiopathic pathology showed improvement. LESSONS The idiopathic pathology was the localized dorsal arachnoid adhesion that responded to surgical treatment. The secondary pathology produced disturbed venous circulation of the spinal cord by extensive adhesions. Lysis of the thickened fibrous membrane with preservation of thin arachnoid over the spinal veins may provide safe decompression. S-S shunt was effective if the syrinx extended to the level of normal subarachnoid space.

BACKGROUNDSecondary Chiari malformation can be caused by various disorders associated with cerebrospinal fluid (CSF) leakage at the spinal level. In this report, the authors describe a rare case of secondary Chiari malformation caused by excessive CSF absorption through the enlarged spinal arachnoid villi–like structure.OBSERVATIONSA 20-year-old woman presented with progressive severe headache and posterior neck pain. Magnetic resonance imaging showed tonsillar herniation and decreased subarachnoid space around the spinal cord. A hypointense signal area was observed in the ventral spinal canal on a T2-weighted image. An axial image revealed multiple small, arachnoid cyst–like structures at the right T1 nerve root sleeve. Direct surgery revealed that the cyst-like structures were continuous with the arachnoid membrane and protruded into the abnormally large epidural venous sinus. The cyst-like structures were resected, and the dural sleeve was repaired using fascia. The patient showed good improvement of symptoms after surgery.LESSONSExcessive CSF absorption through the enlarged spinal arachnoid villi–like structure can cause secondary Chiari malformation. Neurosurgeons should be aware of this unusual mechanism of CSF leakage. Simple posterior fossa decompression will be ineffective or even harmful.

The purpose of this study was to test the psychometric properties of the Japanese version of Frenchay Dysarthria Assessment (FDA-2) and to use this tool to describe the features of speech in patients with Duchenne muscular dystrophy (DMD).The Japanese version of FDA-2 was culturally adapted, and reliability and validity were examined in 22 and 50 patients, respectively. The Japanese version of FDA-2 was administered to 51 patients with DMD. Multiple regression analysis was performed to identify factors related to FDA-2 scores.Inter-/intra-rater reliabilities (ICCs) and internal consistency (Cronbach's α) for total scores were 0.76, 0.97, and 0.94 respectively. For construct validity, two-way ANOVA showed a significant interaction between the disorders and FDA-2 sections (The results showed that the Japanese version of FDA-2 has satisfactory reliability and validity. The present study demonstrated the features of dysarthria and related factors in patients with DMD.Implications for rehabilitationIn Duchenne muscular dystrophy (DMD), an absent or defective dystrophin protein causes progressive weakness of respiratory and oropharyngeal muscles, both of which are crucial contributors to speech production.This study shows that the Japanese version of FDA-2 has satisfactory reliability and validity compared to original version.The Japanese version of FDA-2 characterizes dysarthria in patients with DMD in this cohort.

Introduction: We studied the clinical and nerve pathological features in 6 patients whose low back pain (LBP) was relieved by superior cluneal nerve (SCN) neurectomy to determine whether nerve compression was the mechanism underlying this type of LBP. Methods: ALL 6 patients (7 nerves) underwent SCN neurectomy for intractable LBP. Their clinical outcomes and the pathological features of 7 nerves were reviewed. Results: All patients reported LBP relief immediately after SCN neurectomy. Pathological study of the 7 resected nerves showed marked enlargement, decreased myelinated fiber density, an increase in thinly myelinated fibers (n=2), perineurial thickening (n=5), subperineurial edema (n=4), and Renaut bodies (n=4). At the distal end of one enlarged nerve we observed a moderate reduction in the density, and marked reduction in the number, of large myelinated fibers. Discussion: The pathological findings and effectiveness of neurectomy suggest that in our patients, SCN neuropathy likely elicited LBP via nerve compression. This article is protected by copyright. All rights reserved.

Object Low back pain (LBP) attributable to fusion failure, implant failure, infection, malalignment, or adjacent segment disease may persist after lumbar fusion surgery (LFS). Superior cluneal nerve (SCN) entrapment neuropathy (SCNEN) is a clinical entity that can produce LBP. We report that SCNEN treatment improved LBP in patients who had undergone LFS. Methods Between April 2012 and August 2015, we treated 8 patients (4 men and 4 women ranging in age from 38 to 88 years; mean age, 69 years) with SCNEN for their LBP after LFS. Our criteria for the diagnosis of SCNEN included a trigger point over the posterior iliac crest 7 cm from the midline and numbness and radiating pain in the SCN area upon compression of the trigger point. Symptom relief was obtained in more than 75% of patients within 2 h of inducing a local nerve block at the trigger point in the buttocks. The mean postoperative follow-up period was 28 months (range, 9-54 months). Results LBP was unilateral in 3 and bilateral in 5 patients. The senior author (T.I.) operated all patients for SCNEN under local anesthesia because they reported recurrence of pain after the analgesic effect of repeat injections wore off. This led to a significant improvement of their LBP. Conclusions SCNEN should be considered in patients reporting LBP after LFS. Treatment of SCNEN may be a useful option in patients with failed back surgery syndrome after LFS.

STUDY DESIGN Prospective observational cohort study. OBJECTIVE The objective of this study was to present the long-term surgical outcomes of operative treatment for superior cluneal nerve (SCN) entrapment neuropathy (SCNEN) and to analyze the causes of poor results and further treatment required. SUMMARY OF BACKGROUND DATA There are a few reports of the outcomes of surgical treatment for SCNEN, and most studies describe results for operations conducted under general anesthesia with short follow-up periods. METHODS Surgery was performed for SCNEN in 52 consecutive patients on 79 sides, excluding patients who had undergone previous surgery on the lumbar spine. Entrapment was unilateral in 25 patients and bilateral in 27. The mean postoperative follow-up period was 41.3 months (range, 29-58 months). All patients had received conservative treatment without improvements, and operations were performed under local anesthesia. RESULTS Twenty-three cases (44%) involved only low-back pain (LBP), and 31 cases (60%) involved LBP associated with leg numbness or pain. The mean number of SCN branches decompressed in the operative field at the first operation was 1.4 (range, 1-4 branches). There were no local or systemic complications during or after the operation. All patients reported symptom improvement, but LBP caused by SCNEN recurrence was reported for 10 sides (13%) in seven patients who subsequently underwent repeat surgery. In the second surgery, the number of additionally treated SCN branches was 2.0 (range, 1-5). Additional surgeries were performed in two cases for lumbar disorders. All patients showed significant improvement at the last follow-up visit (P

Objective The diagnosis of common peroneal nerve entrapment neuropathy (CPNEN) is based on clinical symptoms and nerve conduction studies. However, nerve conduction studies may not detect abnormalities. Under the hypothesis that repetitive plantar flexion that loads the peroneal nerve (PN) at the entrapment point without lumbar loading would be a useful CPNEN provocation test, we evaluated the repetitive plantar flexion (RPF) test as an adjunct diagnostic tool for CPNEN. The study design was a retrospective analysis of prospectively collected data. Methods Our study population consisted of 18 consecutive patients whose ipsilateral CPNEN improved significantly after PN neurolysis. Using repetitive ankle plantar flexion as a CPNEN provocation test, results were recorded as positive when it elicited numbness and/or pain in the affected area of the PN. Results The RPF test induced symptoms on all affected sides in the course of 57.4 seconds (range, 14–120 seconds). In 3 patients it induced numbness in the affected area of the PN in the normal leg. Receiver operating characteristic analysis showed that the diagnostic sensitivity and accuracy of the test were 94.4% each. The suggested cutoff point was 110 seconds and the area under the receiver operating characteristic curve was 0.97 (95% confidence interval 0.93–1.02). The positive and the negative predictive values were 89.5% and 94.1%, respectively. Conclusions Our simple RPF test elicited the symptoms of CPNEN and our provocation test helped to identify dynamic PN entrapment neuropathy as the origin of intermittent claudication.

Here we report our treatment results of low back and leg pain(LBLP)considering para-lumbar spine disease(PLSD)and peripheral nerve neuropathy(PNN).We enrolled 103 patients who were admitted to our institute for LBLP treatment between January and December in 2014. For the treatment, we preferentially performed intensive block therapy for PLSD.Among 103 patients, 89 patients had PLSD. In 85 patients, we performed intensive block therapy and 82 patients experienced short-term improvement of symptoms. In 35 of these 82 patients, lumbar spine and/or PNN surgical treatment was required as the effect of block therapy was transient. Intensive block therapy was effective in 47 of 103 patients(45.6%), and the remaining patients required surgical treatment(PLSD and/or PNN:31 cases, lumbar spine:13 cases, both:8 cases).Among 103 patients with LBLP, intensive block therapy for PLSD and PNN was useful for short-term symptom improvement in 82 patients(79.6%), and for long-term symptom improvement in 47 patients(45.6%)as evaluated at the final follow-up. Surgical treatment of PLSD and/or PNN was required in 39 patients(37.9%). These results suggested that treatment of PLSD and PNN might yield good results for patients with LBLP.

Peroneal nerve entrapment neuropathy (PNEN) is one cause of numbness and pain in the lateral lower thigh and instep, and of motor weakness of the extensors of the toes and ankle. We report a less invasive surgical procedure performed under local anesthesia to treat PNEN and our preliminary outcomes. We treated 22 patients (33 legs), 7 men and 15 women, whose average age was 66 years. The mean postoperative follow-up period was 40 months. All patients complained of pain or paresthesia of the lateral aspect of affected lower thigh and instep; all manifested a Tinel-like sign at the entrapment point. As all had undergone unsuccessful conservative treatment, we performed microsurgical decompression under local anesthesia. Of 19 patients who had undergone lumbar spinal surgery (LSS), 9 suffered residual symptoms attributable to PNEN. While complete symptom abatement was obtained in the other 10 they later developed PNEN-induced new symptoms. Motor weakness of the extensors of the toes and ankle [manual muscle testing (MMT) 4/5] was observed preoperatively in 8 patients; it was relieved by microsurgical decompression. Based on self-assessments, all 22 patients were satisfied with the results of surgery. PNEN should be considered as a possible differential diagnosis in patients with L5 neuropathy due to lumbar degenerative disease, and as a causative factor of residual symptoms after LSS. PNEN can be successfully addressed by less-invasive surgery performed under local anesthesia.

Objective. Sacroiliac joint (SIJ) pain originating from the posterior ligament manifests in not only the buttocks but also the groin and lower extremities and thus may be difficult to discern from pain secondary to other lumbar disorders. We aimed to develop a simple clinical diagnostic tool to help physicians distinguish between patients with SIJ pain originating from the posterior ligament and those with lumbar disc herniation (LDH) or lumbar spinal canal stenosis (LSS). Design. Prospective case-control study. Patients and Methods. We evaluated 62 patients with SIJ pain originating from the posterior ligament and 59 patients with LDH and LSS. Pain areas, pain increasing positions, provocation test, and tenderness points were investigated. A scoring system based on multivariate logistic regression equations using the investigated items was developed. Results. Two pain areas (the posterosuperior iliac spine (PSIS) detected by the one-finger test and groin), pain while sitting on a chair, provocation test, and two tenderness points (PSIS and the sacrotuberous ligament) had high odds ratios (range, 25.87–1.40) and were used as factors in the scoring system. An integer score derived from the regression coefficient and clinical experience was assigned to each identified risk factor. The sum of the risk score for each patient ranged from 0–9. This scoring system had a sensitivity of 90.3% and a specificity of 86.4% for a positivity cutoff point of 4. Conclusion. The scoring system can help distinguish between patients with SIJ pain originating from the posterior ligament and those with LDH and LSS.

Previous studies have indicated that cerebrovascular diseases (CVDs) seem to increase the occurrence of unruptured intracranial aneurysms (UIAs). However, this maybe explained by the fact that CVDs and UIAs share common risk factors, such as hypertension (HT) and smoking. To clarify the impact of atherosclerotic risk factors on cerebral aneurysmal formation, we explored the incidence of UIAs and their locations in healthy controls and patients with CVD, who frequently have atherosclerotic risk factors. This study included consecutive 283 asymptomatic healthy adults and 173 acute stroke patients, from patients diagnosed with acute cerebral hemorrhage or cerebral infarction and admitted to our hospital. The incidence, maximum diameter, and location of UIAs were evaluated, and we also investigated the following factors: age, gender, current smoking, HT, diabetes mellitus (DM), and dyslipidemia. UIAs were found in 19 of the total 456 subjects (4.2%), 11 of 283 healthy subjects (3.9%), and 8 of 173 stroke patients (4.6%). These differences are not statically significant. The incidence of middle cerebral artery (MCA) aneurysms was significantly higher in the CVD patients than in the healthy controls ( P = .03), and the incidence of paraclinoid aneurysms was significantly higher in the healthy controls than in the CVD patients ( P = .03). Moreover, higher incidences of HTs and CVDs in the MCA aneurysms than in the other locations of UIAs were observed. These results indicate that the impact of atherosclerotic factors on cerebral aneurysmal formation depends on their location and that there is a stronger impact on MCA aneurysms than on paraclinoid aneurysms.

Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the posterior tibial nerve and its branches in the tarsal tunnel. We present our less invasive surgical treatment of TTS in 69 patients (116 feet) and their clinical outcomes. The mean follow-up period was 64.6 months. With the patient under local anesthesia we use a microscope to perform sharp dissection of the flexor retinaculum and remove the connective tissues surrounding the posterior tibial nerve and vessels. To prevent postoperative adhesion and delayed neuropathy, decompression is performed to achieve symptom improvement without excessive dissection. Decompression is considered complete when the patient reports intraoperative symptom abatement and arterial pulsation is sufficient. The sensation of numbness and/or pain and of foreign substance adhesion was reduced in 92% and 95% of our patients, respectively. In self-assessments, 47 patients (68%) reported the treatment outcome as satisfactory, 15 (22%) as acceptable, and 7 (10%) were dissatisfied. Of 116 feet, 4 (3%) required re-operation, initial decompression was insufficient in 2 feet and further decompression was performed; in the other 2 feet improvement was achieved by decompression of the distal tarsal tunnel. Our surgical method involves neurovascular bundle decompression to obtain sufficient arterial pulsation. As we use local anesthesia, we can confirm symptom improvement intraoperatively, thereby avoiding unnecessary excessive dissection. Our method is simple, safe, and without detailed nerve dissection and it prevents postoperative adhesion.

Background The threshold of ischemic tolerance has not been completely identified in human clinical studies. Distal carotid artery pressure can be easily measured through the internal shunt tube during carotid endarterectomy (CEA). To confirm the critical threshold of intracranial arterial pressure and its maximum duration, we investigated the distal internal carotid artery (ICA) pressure and motor-evoked potential (MEP) changes during ICA clamping. Material and Methods Between September 2012 and March 2014, 9 patients (10 sides) with carotid stenosis (70-99%) were surgically treated at our hospital. All CEAs were performed under general anesthesia, and we routinely used a carotid shunt with the intraoperative MEP monitors. When the MEP amplitude decreased to 50% of the control during carotid clamping, the MEP amplitude was defined as significantly reduced. Results The MEP amplitude significantly decreased in 2 of the 10 procedures (20%) during ICA clamping. The mean distal ICA pressure varied widely, ranging from 13 to 48 mm Hg. In seven cases with a mean distal ICA pressure 20 mm Hg, there were no significant changes in the MEP during ICA clamping. However, there were three cases with a mean distal ICA pressure 20 mm Hg, and the MEP amplitude significantly decreased in two of those three patients from 4 to 5 minutes after clamping. Conclusions The present study provides considerable information about a higher incidence of MEP amplitude deterioration in CEA patients with a mean distal ICA pressure 20 mm Hg during ICA clamping.

This study was designed to clarify the effects of donor age on biological features of bone marrow stromal cells (BMSC), one of the candidates for cell transplantation therapy for CNS disorders, because many aged patients might require such therapy. This study was also aimed to test whether ex vivo treatments with granulocyte-colony stimulating factor (G-CSF) could modify biological properties of BMSC from aged donors and enhance its therapeutic effects in an animal model of traumatic brain injury. The BMSC were harvested from young (6-week-old) and aged (100-week-old) rats. The ageing significantly increased the senescence-associated β-galactosidase (SA-β-gal) activity of the cultured BMSC, and decreased their proliferative capacity and production of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). As the next step, the rats were subjected to brain freezing injury by applying liquid nitrogen onto the neocortex through the thinned skull. The 6-week BMSC, 100-week BMSC, G-CSF-treated 100-week BMSC or vehicle were stereotactically injected into the ipsilateral striatum at 7 days post-injury. Transplantation of the 6-week BMSC, but not 100-week BMSC, significantly improved locomotor function. However, treatment of the 100-week BMSC with 0.1 µmol of G-CSF significantly improved their proliferation activity and growth factor production, and recovered therapeutic effects in the injured brain. In conclusion, donor age may largely determine biological aspects of BMSC. G-CSF may contribute to improve the outcome of BMSC transplantation therapy for CNS disorders in aged patients.

Objective Recent studies have indicated that bone marrow stromal cells (BMSCs) have the potential to improve neurological function when transplanted into animal models of cerebral infarct. However, it is still undetermined how the BMSCs should be transplanted to obtain the most efficient therapeutic benefits safely. The aim of this study was to assess whether a thermoreversible gelation polymer (TGP) hydrogel acts as a noninvasive, valuable scaffold in BMSC transplantation for infarct brain. Methods The mice were subjected to permanent middle cerebral artery occlusion. Vehicle, BMSC suspension, or the BMSC-TGP construct was transplanted onto the ipsilateral intact neocortex at 7 days after the insult. Neurological symptoms were assessed throughout the experiments. The fate of the transplanted BMSC was examined 8 weeks after transplantation with immunohistochemistry. Results TGP hydrogel completely disappeared and provoked no inflammation in the host brain. Many transplanted cells were widely engrafted in the ipsilateral cerebrum, including the dorsal neocortex adjacent to the cerebral infarct in the BMSC-TGP construct-treated mice. Their number was significantly larger than in the BMSC-treated mice. The majority were positive for both NeuN and MAP2 and morphologically simulated the neurons. Conclusion The findings suggest that surgical transplantation of tissue-engineered BMSCs onto the intact neocortex enhances the engraftment of donor cells around the cerebral infarct. These data may be useful in developing a noninvasive but efficient paradigm in neural tissue engineering. TGP hydrogel can be a promising candidate for valuable scaffolds in BMSC transplantation for central nervous system disorders because of its unique biochemical properties.

There are few studies that denote whether bone marrow stromal cells (BMSC) and bone marrow-derived mononuclear cells (MNC) show the same therapeutic effects, when directly transplanted into the infarct brain. This study therefore aimed to compare their biological properties and behaviors in the infarct brain. Mouse BMSC were harvested and cultured. Mouse MNC were obtained through centrifugation techniques. Their cell markers were analyzed with FACS analysis. The MNC (10(6) cells; n = 10) or BMSC (2 x 10(5) cells; n = 10) were stereotactically transplanted into the ipsilateral striatum of the mice subjected to permanent middle cerebral artery occlusion at 7 days after the insult. Their survival, migration, and differentiation in the infarct brain were precisely analyzed using immunohistochemistry 4 weeks after transplantation. The MNC were positive for CD34, CD45, CD90, but were negative for Sca-1. The BMSC were positive for CD90 and Sca-1. The transplanted BMSC, but not MNC, extensively migrated into the peri-infarct area. Approximately 20% of the transplanted BMSC expressed a neuronal marker, NeuN in the infarct brain, although only 1.4% of the transplanted MNC expressed NeuN. These findings strongly suggest that there are large, biological differences between MNC and BMSC as cell sources of regenerative medicine for ischemic stroke.

Transplanted bone marrow stromal cells (BMSC) promote functional recovery after spinal cord injury (SCI) through multiple mechanisms. A Rho kinase inhibitor, Fasudil also enhances axonal regeneration. This study was aimed to evaluate whether combination therapy of BMSC transplantation and Fasudil further enhances axonal regeneration and functional recovery in rats subjected to SCI. Fasudil or vehicle was injected for 2 weeks. BMSC or vehicle transplantation into the rostral site of SCI was performed at 7 days after injury. Neurological symptoms were assessed throughout the experiments. Fluoro-Ruby was injected into the dorsal funiculus of the rostral site of SCI at 63 days after injury. The fate of the transplanted BMSC was examined using immunohistochemistry. BMSC transplantation significantly increased the number of Fluoro-Ruby -labeled fibers of the dorsal corticospinal tracts at the caudal site of SCI, enhancing functional recovery of the hind limbs. Some of the engrafted BMSC were positive for Fluoro-Ruby, neuronal specific nuclear protein and microtubule-associated protein-2, suggesting that they acquired neuronal phenotypes and built synaptic connection with the host's neural circuits. Fasudil treatment also improved axonal continuity, but did not promote functional recovery. Combination therapy dramatically increased the number of Fluoro-Ruby-labeled fibers of the dorsal corticospinal tracts at the caudal site of SCI, but did not further boost the therapeutic effects on locomotor function by BMSC transplantation. The findings suggest that BMSC transplantation and Fasudil provide synergistic effects on axon regeneration after SCI, although further studies would be necessary to further enhance functional recovery.

Diffuse axonal injury (DAI) often leads to persistent cognitive dysfunction in spite of the lack of gross lesions on MRI. Therefore, this study was aimed to evaluate whether transplanted bone marrow stromal cells (BMSC) can improve DAI-induced cognitive dysfunction or not. The rats were subjected to impact acceleration head injury, using a pneumatic high-velocity impactor. The BMSC were harvested from the mice and were cultured. The BMSC (4.0 x 10(5) cells) or vehicle were stereotactically transplanted into the right striatum at 10 days post-injury. Cognitive function analysis was repeated at 1, 2, and 4 weeks post-injury, using the Morris water maze test. Histological analysis was performed at 2, 8 and 20 weeks post-injury, using double fluorescence immunohistochemistry. Transplanted BMSC were widely distributed in the injured brain and gradually acquired the phenotypes of neurons and astrocytes over 20 weeks. In addition, they significantly improved DAI-induced cognitive dysfunction as early as 2 weeks post-injury, although their processes of neuronal differentiation were not completed at this time point. The findings suggest that the engrafted BMSC may exhibit this early beneficial effect on cognitive function by producing neuroprotective or neurotrophic factors. In conclusion, direct transplantation of BMSC may serve as a novel therapeutic strategy to enhance the recovery from DAI-induced cognitive impairment.

OBJECTIVE: Recent studies have indicated that bone marrow stromal cells (BMSCs) have the potential to improve neurological function when transplanted into animal models of spinal cord injury (SCl). However, it is still unclear how the transplanted BMSCs promote functional recovery after SCI. In this study, therefore, we evaluated how the transplanted BMSCs restore the function of the dorsal corticospinal tracts in the injured spinal cord. METHODS: The rats were subjected to incomplete SCI by means of a pneumatic impact device. BMSC or vehicle transplantation into the rostral site of SCl was performed at 7 days after injury. Neurological symptoms were assessed throughout the experiments. Fluoro-Ruby was injected into the dorsal funiculus of the rostral site of SCl at 63 days after injury. The fate of the transplanted BMSCs was examined using immunohistochemistry. RESULTS: BMSC transplantation significantly enhanced functional recovery of the hind limbs. The number of Fluoro-Ruby-labeled fibers of the dorsal corticospinal tracts at the caudal site of SCI was significantly higher in the BMSC-transplanted animals than in the vehicle-transplanted animals. Some of the engrafted BMSCs were positive for Fluoro-Ruby, NeuN, and MAP2 in the gray matter, suggesting that they acquired neuronal phenotypes and built synaptic connection with the host's neural circuits. Others in the white matter morphologically simulated the astrocytes and were also positive for glial fibrillary acidic protein. CONCLUSION: The findings suggest that the transplanted BMSCs acquire neural cell phenotypes around the injury site and contribute to rebuild the neural circuits, including the corticospinal tract, promoting functional recovery of the hind limbs.

This study was aimed to assess whether ex vivo treatment with granulocyte-colony stimulating factor (G-CSF) modifies biological properties of bone marrow stromal cells (BMSC) and enhances functional recovery by BMSC transplantation into infarct brain. Immunohistochemistry was conducted to characterize the cultured BMSC. The pharmacological effects of G-CSF on their proliferation, cell cycle, and growth factor production were precisely analyzed, using FACS and ELISA techniques. Non-treated or G-CSF treated BMSC were stereotactically transplanted into the mice brain subjected to cerebral infarct, and its effects on functional and histological aspects were evaluated. The BMSC expressed the receptor for G-CSF. Treatment with 0.1muM of G-CSF significantly enhanced the proliferation of BMSC by increasing their population in S phase, and increased their production of SDF-1alpha, HGF, and NGF. When transplanted into infarct brain, G-CSF treated BMSC significantly improved motor function as early as 2 weeks after transplantation, whereas non-treated BMSC did 4 weeks after transplantation. These findings strongly suggest that G-CSF may enhance the proliferation and growth factor production of the cultured BMSC and accelerate functional restoration by BMSC transplantation. Such pharmacological "activation" of the BMSC may contribute to successful clinical application of BMSC transplantation therapy for ischemic stroke.

In this study, we propose a simple hopping mechanism using the vibration of a two-degree-of-freedom system for a wheel-based stair-climbing robot. The robot, consisting of two bodies connected by springs and a wire, hops by releasing energy stored in the springs and quickly travels using wheels mounted in its lower body. The trajectories of the bodies during hopping change in accordance with the design parameters, such as the reduced mass of the two bodies, the mass ratio between the upper and lower bodies, the spring constant, the control parameters such as the initial contraction of the spring and the wire tension. This property allows the robot to quickly and economically climb up and down stairs, leap over obstacles, and landing softly without complex control. In this paper, the characteristics of hopping motion for the design and control parameters are clarified by both numerical simulations and experiments. Furthermore, using the robot design based on the results the abilities to hop up and down a step, leap over a cable, and land softly are demonstrated.

We propose a simple hopping mechanism using vibration of a two-degrees-of-freedom (2-DOF) system for a fast stair-climbing robot. The robot, consisting of two bodies connected by springs and a wire, hops by releasing energy stored in springs and travels quickly using wheels mounted on its lower body. The trajectories of bodies during hopping change based on mechanical design parameters such as reduced mass of the two bodies, the mass ratio between the upper and lower bodies, and spring constant, and control parameters such as initial contraction of the spring and wire tension. This property allows the robot to quickly and economically climb stairs and land softly without complex control. In this paper, we propose a mathematical model of the robot and investigate required tread length for continuous hopping to climb a flight of stairs. Furthermore, we demonstrate fast stair-climbing and soft landing for a flight of stairs in experiments.

We propose a simple hopping mechanism using the vibration of a two-degrees-of-freedom (DOF) system for a fast stair-climbing robot. The robot, consisting of two bodies connected by springs, hops by releasing energy stored in springs and travels quickly using wheels mounted on its lower body. The trajectories of bodies during hopping change based on design parameters such as the reduced mass of the two bodies, mass ratio between the upper and lower bodies, spring constant, and control parameters such as initial contraction of the spring and wire tension. This property allows the robot to quickly and economically climb stairs and land softly. In this paper, the characteristics of hopping for the design and control parameters are clarified by both numerical simulation and experiments. Furthermore, fast stair climbing and soft landing are demonstrated.

当院におけるt-PAを用いた超急性期虚血性脳血管障害の治療は2005年12月より開始され2007年2月まで計41例に施行してきた. 今回, 我々はそれまでにおける全症例の経過とその成績について様々な角度から検討を加え, t-PA療法の有効性や問題点に関し考察したので報告する. 当院では搬入後の効率化を図るためにプロトコールを基に進めているが, 発症よりrt-PA投与までの平均時間は約106分と早期に対処できていた. 治療成績は24時間後のNIHSSに関し34例で改善しており, 7例がprogressive strokeであった. 1カ月を経過した症例38例中35例で改善しているが, 3カ月後の時点では32例中28例で改善を示し, 非常に有効性が認められた. 2例が原疾患である脳梗塞にて死亡している. 合併症である脳出血は一例も認められなかったが, 皮下出血を3例に認められた. 経過中増悪した症例の原因は再塞栓, 主幹動脈の狭窄性病変, dementiaなどが挙げられた. 病態は塞栓症が19例, アテローマ血栓症が14例, ラクナ梗塞が6例であり, いずれも同様な改善傾向を示した. rt-PAによる脳梗塞の治療は病態に関わらず1カ月後, 3カ月後と改善が認められ有効であると考えられた.

The clinical features and etiology of low back pain and buttock pain remain poorly understood. We report ten patients with buttock pain who underwent gluteus medius muscle (GMeM) decompression under local anesthesia. Between December 2012 and November 2013 we surgically treated ten patients (four men, six women; mean age 65.1 years) for buttock pain. The affected side was unilateral in seven and bilateral in three patients (total sites, n = 13). The interval from symptom onset to treatment averaged 174 months; the mean postoperative follow-up period was 24 months. Decompression of the tight gluteal aponeurosis over the GMeM was performed under local anesthesia. Assessment of the clinical outcomes was on the numeric rating scale (NRS) for low back pain (LBP), the Japanese Orthopedic Association (JOA) score, and the Roland–Morris Disability Questionnaire (RDQ) score before and at the latest follow-up after treatment. There were no intraoperative surgery-related complications. The buttock pain of all patients was improved after surgery; their NRS decreased from 7.0 to 0.8 and JOA and RMDQ scores indicated significant improvement (p

OBJECT Superior cluneal nerve (SCN) entrapment neuropathy (SCNEN) is a cause of low-back pain (LBP) that can be misdiagnosed as a lumbar spine disorder. The clinical features and etiology of LBP remain poorly understood. In this study, 5 patients with intermittent LBP due to SCNEN who had previously received conservative treatment underwent surgery. The findings are reported and the etiology of LBP is discussed to determine whether it is attributable to SCNEN. METHODS Intermittent LBP is defined as a clinical condition in which pain is induced by standing or walking but is absent at rest. Between April 2012 and March 2013, 5 patients in this study who had intermittent LBP due to SCNEN underwent surgery. The patients included 3 men and 2 women, with a mean age of 66 years. The affected side was unilateral in 2 patients and bilateral in 3 (total sites, 8). The interval from symptom onset to treatment averaged 51.4 months; the mean postoperative follow-up period was 17.6 months. The clinical outcomes were assessed using the numerical rating scale (NRS) for LBP, the Japanese Orthopaedic Association (JOA) scale, and the Roland-Morris Disability Questionnaire (RDQ) preoperatively and at the last follow-up; these data were analyzed statistically. RESULTS None of the 5 patients reported LBP at rest. Intermittent LBP involving the iliac crest and buttocks was induced by standing or walking an average of 136 m. In 2 patients with unilateral involvement, LBP was improved only by SCN block. Surgeries were performed on 6 sites in 5 patients because the SCN block was only transiently effective. Patients’ SCNs penetrated the orifice of the thoracolumbar fascia. SCN kinking at the orifice was exacerbated at the lumbar-extension provocation posture, and radiating pain increased upon manual intraoperative compression of the SCN in this posture. After releasing the SCN surgically, disappearance of the pain was intraoperatively confirmed by manual compression of the SCN with the patients in the lumbar-extension posture. Surgery was effective in all 5 patients, and all clinical outcome scores indicated significant improvement (p < 0.05). CONCLUSIONS To the authors’ knowledge, this is the first report of patients with intermittent LBP due to SCNEN. Clinical and surgical evidence presented suggests that their LBP was exacerbated by lumbar extension and that symptom relief was obtained by SCN block or surgical release of the SCN entrapment. These results suggest that SCNEN should be considered as a causal factor in patients for whom walking elicits LBP.

n patients with Parkinson disease (PD), postural abnormalities and increased muscle tonus lead to musculoskeletal I problems. The incidence of such problems was significantly higher in patients with PD than in an age-matched control group comprising patients with stroke and brain tumor. Low back pain (LBP) in particular was reported more frequently by patients with PD; in approximately 50%, it negatively affected their quality of life and activities of daily living (ADL). It is difficult to treat LBP in patients with PD, and the results of surgery to address their spinal diseases are unsatisfactory.

Background: Superior cluneal nerve entrapment neuropathy (SCN-EN) may contribute to low back pain (LBP). However, it is often misdiagnosed as lumbar spine disorder and poorly understood. Methods: Between April 2012 and September 2013, we treated 27 patients (3 men, 24 women; mean age 75.0 years) with LBP due to SCN-EN elicited by vertebral compression fractures. Symptoms were unilateral in 4 patients and bilateral in 23 patients. The interval between symptom onset and treatment averaged 10.8 months; the mean postoperative follow-up period was 19.0 months. The clinical outcomes were assessed utilizing the numeric rating scale (NRS) for LBP, the Japanese Orthopedic Association (JOA) score, and the Roland–Morris Disability Questionnaire (RDQ) before and after treatment (e.g., until the latest follow-up). Results: LBP in 17 patients was immediately improved by SCN block only. The remaining 10 patients required surgery (involving 18 sites) as SCN blocks were only transiently effective. Operative intervention resulted in the immediate and continued improvement of their LBP. Notably, their NRS decreased from 7.4 to 1.5, their RDQ scores from 19.6 to 7.0, and their JOA scores increased from 10.7 to 20.3. Conclusions: In this series, 27 patients with LBP due to SCN-EN responded either to SCN blocks (17 patients) or surgical release of SCN entrapment (10 patients at 18 sites).

Peroneal nerve entrapment neuropathy (PEN) is generally known as a drop foot with sensory disturbance. However, some patients experience numbness and pain in the affected area without severe paresis due to PEN. We report the clinical features and our surgical results of PEN cases.We encountered 17 cases of PEN. The patients were 7 females and 10 males and their ages ranged from 30 to 78 years(average 56.1 years). In these cases, conservative therapy was unsuccessful;therefore, we performed surgical treatment for PEN.Among the 17 cases, 4 were of bilateral and 13 were of unilateral PEN. There was no severe paresis, as in drop foot;however, mild paresis (4/5, manual muscle test, MMT) was noted in 15 cases. In all cases, intermittent claudication presented, which ranged from 10 to 800 m (average 150 m). In 13 cases, radiological abnormality of the lumbar region was noted and 8 cases had a history of lumbar surgery (they had failed back surgery syndrome). In all the cases, we performed neurolysis of the peroneal nerve under local anesthesia;there was no surgical complication. After the surgery, symptoms improved, and the numerical rating of the lower limb improved from 8.6/10 to 0.8/10. Intermittent claudication also improved in all of the cases.We successfully treated 17 cases of PEN, which had lower limb pain without severe paresis, as in drop foot. Our results indicate that PEN should be recognized as a cause of intermittent claudication. Neurolysis for PEN under local anesthesia is less invasive and is useful for the treatment of lower limb pain.

Background. We tested the flow characteristics of a new siphon-reducing device, the Shunt Assistant Valve™ (SAV) combined with a Codman-Hakim™ (CH) programmable valve and studied 4 clinical cases. We discussed the efficacy of the SAV at preventing low pressure syndrome secondary to overdrainage. Materials and methods. In the horizontal position the closing pressure (CP) of the SAV was 0. The SAV was available in five different pressure ranges for the vertical position: 15, 20, 25, 30, and 35 cmH2O. A bench test was performed in order to obtain pressure-flow curves for the SAV under various conditions. We investigated the simulation of the postural change of the flow performance of the new device. We implanted an SAV in 4 patients who already had an implanted CH valve. Postural changes of the shunt flow and intracranial pressure (ICP) were measured before and after the addition of the SAV. Results. Bench test: in the horizontal position the flow increased in proportion to the pressure difference. For all SAVs it reached 14 to 16 mL/min when the pressure difference was 50 cmH2O. A tantalum sphere determined the CP of the SAV with a maximum in the vertical position. The flow in the vertical position was significantly decreased in comparison with the horizontal position. The external pressures did not influence the flow. Simulation: in adults shunt flow in the supine position was sufficient at both the low and the high ICP stages. When the SAV 20 and the CH valve (CP=8 cmH2O) was used in the sitting position we found a reduction of the flow 70–80% compared with the flow-rate found for the CH valve alone. When the CP of the CH valve was adjusted up to 20 cmH2O, we found a further reduction of the flow of 27–50% in the sitting position and overdrainage was effectively prevented. With this combination the flow in the sitting position significantly decreased in paediatric hydrocephalus and became zero, indicating the possibility of underdrainage in children. Clinical results: in 4 patients with overdrainage symptoms we found that these subsided after the additional implantation of the SAV. The ICP increased and the shunt flow decreased in both the supine and the sitting positions. Conclusion. The SAV effectively decreased the shunt flow in the erect position. Combined use of the SAV with the CH valve is an alternative treatment for patients with overdrainage, especially in patients in whom the increase of the CP of the CH valve alone had failed to control overdrainage.

Since the introduction of carotid stenting (CAS), a combined treatment for bilateral lesions using carotid endarterectomy (CEA) and CAS has been developed. However, there has been only 1 report about CEA then CAS. Herein we describe 2 patients with bilateral severe carotid stenosis who were treated by CEA for the symptomatic side and CAS for the contralateral asymptomatic side. A 71-year-old man underwent CEA for the symptomatic side. Although the patient suffered hyperperfusion syndrome after CEA, he recovered fully after 3 weeks of rehabilitation. Two months later, CAS was performed for the asymptomatic side, and he was discharged with no deficit. A 67-year-old man underwent CEA for the symptomatic side. The patient developed no postoperative neurologic deficits except for hoarseness. Four weeks later, CAS was performed for the contralateral asymptomatic side. After the procedure, however, severe hypotension occurred, and treatment by continuous injection of catecholamine was necessary to maintain systematic blood pressure. The patient was ultimately discharged with no deficit. The combined therapy of CAS for the asymptomatic side and then CEA for the symptomatic side has been recommended by several authors. However, one of the problems of this strategy is the higher incidence of postprocedural hemodynamic complications, and hypotension after CAS may be dangerous for the symptomatic hemisphere. We suggest a combined therapy using CEA for the symptomatic side and then CAS for the asymptomatic side can be 1 beneficial treatment option for patients with bilateral carotid stenosis without coronary artery disease.

Superior cluneal nerve (SCN) entrapment neuropathy is a known cause of low back pain. Although surgical release at the entrapment point of the osteofibrous orifice is effective, intraoperative identification of the thin SCN in thick fat tissue and confirmation of sufficient decompression are difficult. Intraoperative indocyanine green video angiography (ICG-VA) is simple, clearly demonstrates the vascular flow dynamics, and provides real-time information on vascular patency and flow. The peripheral nerve is supplied from epineurial vessels around the nerve (vasa nervorum), and the authors now present the first ICG-VA documentation of the technique and usefulness of peripheral nerve neurolysis surgery to treat SCN entrapment neuropathy in 16 locally anesthetized patients. Clinical outcomes were assessed with the Roland-Morris Disability Questionnaire before surgery and at the latest follow-up after surgery. Indocyanine green video angiography was useful for identifying the SCN in fat tissue. It showed that the SCN penetrated and was entrapped by the thoracolumbar fascia through the orifice just before crossing over the iliac crest in all patients. The SCN was decompressed by dissection of the fascia from the orifice. Indocyanine green video angiography visualized the SCN and its termination at the entrapment point. After sufficient decompression, the SCN was clearly visualized on ICG-VA images. Low back pain improved significantly, from a preoperative Roland-Morris Questionnaire score of 13.8 to a postoperative score of 1.3 at the last follow-up visit (p < 0.05). The authors suggest that ICG-VA is useful for the inspection of peripheral nerves such as the SCN and helps to identify the SCN and to confirm sufficient decompression at surgery for SCN entrapment.

This study was designed to clarify the effects of donor age on biological features of bone marrow stromal cells (BMSC), one of the candidates for cell transplantation therapy for CNS disorders, because many aged patients might require such therapy. This study was also aimed to test whether ex vivo treatments with granulocyte-colony stimulating factor (G-CSF) could modify biological properties of BMSC from aged donors and enhance its therapeutic effects in an animal model of traumatic brain injury. The BMSC were harvested from young (6-week-old) and aged (100-week-old) rats. The ageing significantly increased the senescence-associated β-galactosidase (SA-β-gal) activity of the cultured BMSC, and decreased their proliferative capacity and production of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). As the next step, the rats were subjected to brain freezing injury by applying liquid nitrogen onto the neocortex through the thinned skull. The 6-week BMSC, 100-week BMSC, G-CSF-treated 100-week BMSC or vehicle were stereotactically injected into the ipsilateral striatum at 7 days post-injury. Transplantation of the 6-week BMSC, but not 100-week BMSC, significantly improved locomotor function. However, treatment of the 100-week BMSC with 0.1 µmol of G-CSF significantly improved their proliferation activity and growth factor production, and recovered therapeutic effects in the injured brain. In conclusion, donor age may largely determine biological aspects of BMSC. G-CSF may contribute to improve the outcome of BMSC transplantation therapy for CNS disorders in aged patients.

✓ Epidermal growth factor (EGF) content in urine from patients with glial tumors was examined by radioimmunoassay techniques with labeled human EGF and its rabbit EGF polyclonal antibody. There was no cross-reaction with transforming growth factor-α, which has a common receptor with EGF. Forty glial tumors were divided into three groups according to the clinical stage: Samples from Group A patients were obtained before therapy and/or after biopsy; in these patients a large volume of tumor was apparent on computerized tomography (CT). Group B samples were obtained after gross total removal of the tumor and/or chemo- and radiation therapy; these patients showed a small volume of residual tumor on CT. Samples from Group C patients were obtained after gross tumor total removal and/or chemo- and radiation therapy; no tumor was detected on CT scans in these patients. Urinary EGF levels in Group A samples were statistically significantly higher than in samples from healthy individuals (p < 0.001), Group B patients (p < 0.10), and Group C patients (p < 0.02). In addition, high-grade glial tumors in Group A cases showed a significantly higher level of urinary EGF than low-grade tumors in Group A patients (p < 0.05), or patients with meningioma (p < 0.02), metastatic brain tumor (p < 0.05), and cerebral infarction (p < 0.001). Longitudinal changes of urinary EGF levels in glioma patients mostly synchronized with the clinical course and therapeutic interventions. Therefore, urinary EGF, as a glial tumor marker, may be of practical value for diagnosing a malignant glioma and evaluating for the efficacy of chemo- and radiation therapy.

In this chapter, we introduce a stair-climbing robot developed in our laboratory. This robot consists basically of two body parts connected by springs, and hops as a result of the vibration of a two-degrees-of-freedom (2-DOF) system. The excellent combination between the frequencies of the robotic body vibration and the tread-riser interval of stairs enables a small and simple robot fast stair climbing, soft landing, and energy saving. In an attempt to give the robot mobility in an environment such as an office building having steps and stairs, various mechanisms have been proposed and developed. Each one of which has different characteristics. For example, wheel-based robots are very simple in terms of both mechanical design and control, and they can travel quickly and stably. But their size tends to be big for climbing stairs, as they cannot surmount a riser higher than their wheel radius. On the other hand, although crawler-type robots can climb over a riser higher than a wheel-based robot, they are slow and noisy. Typical examples of crawler-type robots are TAQT (Hirose et al., 1992) that can carry a human and Kenaf (Yoshida et al., 2007) for rescue operations. Legged robots, especially humanoid ones, are well suited for climbing stairs, but require many DOFs and complex control. Honda’s ASIMO (ASIMO OFFICIAL SITE), AIST’s HRP (Harada et al., 2006) and Waseda University’s legged robot (Sugahara et al., 2007) are good examples. In addition, the hybrids of these types have been proposed and have improved upon mutual demerits. Chari-be (Nakajima et al., 2004), with two wheels and four legs, travels quickly on its wheels over flat terrain, and climbs using its legs in rough terrain such as a step and stairs. A biped-type robot with a wheel at the tip of its legs (Matsumoto et al., 1999) climbs stairs smoothly. RHex (Altendorfer et al., 2001) has six compliant rotary legs and travels speedily not only up and down stairs, but also even uncertain terrain such as a swamp. Moreover, modular robots such as an articulated snakelike robot and special mechanisms for stairs have also been proposed. Yim’s snake-like robot (Yim et al., 2001) climbs stairs, transforming its own loop form into a stair shape. These excellent mechanisms have improved the manoeuvrability of the robot for rough terrain, but as most are general-purpose robots for rough terrain, a more specialized mechanism must be developed if we focus solely on stair-climbing ability in an office building. 3

Background and Purpose Diffuse axonal injury (DAI) often leads to persistent cognitive dysfunction in spite of the lack of gross lesions on magnetic resonance (MR) imaging. Therefore, in this study, we aimed to develop a highly controlled and reproducible model of DAI that simulates post-traumatic cognitive dysfunction in humans; we aimed to investigate whether the intracerebral transplantation of bone marrow stromal cells (BMSCs) improved cognitive function in this model.

Recent studies have indicated that bone marrow stromal cells (BMSCs) have the potential to improve neurologic function when transplanted into animal cerebral infarct models. However, it is still undetermined how the BMSCs should be transplanted to safely obtain the most efficient therapeutic benefits. Therefore, this study was carried out aiming to assess whether a thermoreversible gelation polymer (TGP) hydrogel would act as a noninvasive. valuable scaffold in BMSC transplantation for brain infarct. Mice were subjected to permanent middle cerebral artery occlusion. Vehicle, BMSC suspension, or a BMSC-TGP construct was transplanted onto the ipsilateral intact neocortex at 7 days after the insult. The TGP hydrogel completely disappeared and provoked no inflammation in the host brain. In the BMSC-TGP construct-treated mice, many transplanted cells were widely engrafted in the ipsilateral cerebrum, including the dorsal neocortex adjacent to the cerebral infarct. The number of these transplanted cells was significantly larger than that in the BMSC-treated mice; the majority of the cells were positive for both neuronal nuclear antigen (NeuN) and microtubule-associated protein 2 (MAP2) and morphologically simulated neurons. These findings suggest that the surgical transplantation of tissue-engineered BMSCs onto the intact neocortex enhances the engraftment of donor cells around a cerebral infarct. TGP hydrogel, because of its unique biochemical properties, could be a promising candidate as a valuable scaffold in BMSC transplantation for central nervous system disorders.

Recent studies have indicated that bone marrow stromal cells (BMSCs) have the potential to improve neurological function when transplanted into animal models of spinal cord injury (SCI). However, it is still unclear how the transplanted BMSCs promote functional recovery after SCI. In this study. therefore, we evaluated how transplanted BMSCs restore the function of the dorsal corticospinal tract (dCST) in the injured spinal cord. Rats were subjected to incomplete SCI, using a pneumatic impact device. Then BMSC suspension or vehicle was transplanted into the rostral site of the SCI at 7 days after the injury. Fluoro-ruby (FR; Molecular Probes), a fluorescent axonal tracer, was injected into the dorsal funiculus of the rostral site of the SCI 63 days after the injury. BMSC transplantation significantly enhanced functional recovery of the hind limbs. The number of FR-labeled fibers in the dCST at the caudal site of the SCI was significantly higher in the BMSC-transplanted animals than in the vehicle-transplanted animals. Some of the engrafted BMSCs were positive for FR, neuronal nuclear antigen (NeuN). and microtubule-associated protein 2 (MAP2) in the gray matter. The findings suggest that the transplanted BMSCs acquire neural cell phenotypes around the injury site and contribute to rebuilding neural circuits, including those in the CST. promoting functional recovery of the hind limbs.

Background and Purpose It is quite important to track donor cells transplanted into the central nervous system (CNS) in order to evaluate the therapeutic effects of cell transplantation therapy. Therefore, in this preliminary study we aimed to evaluate whether fluorescent quantum dots (QDs) would be useful in noninvasive cell tracking in cerebral infarcts of rats.

This paper deals with experimental investigation on the interaction between inlet freestream turbulence and boundary layers with separation bubble on a low-pressure turbine airfoil under several High Lift conditions. Solidity of the cascade can be reduced by increasing the airfoil pitch by 25%, while maintaining the throat in the blade-to-blade passage. Reynolds number examined is 57000, based on chord length and averaged exit velocity. Freestream turbulence intensity at the inlet is varied from 0.80% (no grid condition) to 2.1% by use of turbulence grid. Hot-wire probe measurements of the boundary layer on the suction surface for Low Pressure (LP) turbines rotor are carried out to obtain time-averaged and time-resolved characteristics of the boundary layers under the influence of the freestream turbulence. Frequency analysis extracts some important features of the unsteady behaviors of the boundary layer, including vortex formation and shedding. Numerical analysis based on high resolution Large Eddy Simulation is also executed to enhance the understanding on the flow field around the highly loaded turbine airfoils. Standard Smagorinsky model is employed as subgrid scale model. Emphasis of the simulation is placed on the relationship of inherent instability of the shear layer of the separation bubble and the freestream turbulence.Copyright © 2009 by ASME