Third primary branch of the posterior ramus of the spinal nerve at the thoracolumbar region: a cadaveric study.

PURPOSE: Spinal column procedures require an accurate understanding of neural pathways relative to the anatomic structure. Since Bogduk's report in 1982, it has been known that the human lumbar posterior ramus of the spinal nerve (PRSN) comprise not two but three primary branches at least in some lumbar segments. The purpose of the current study was to examine the existence of the three primary branches in the thoracic and lumbar segments. METHODS: In this study, we investigated the anatomy of the human PRSN in the thoracic and lumbar segments. Ventral dissection was performed in eight cadavers to determine the anatomy of the PRSN between T1 and L5. RESULTS: At the distal end of a given PRSN, the PRSN divided into three primary branches-medial, intermediate and lateral-in 196 out of 272 segments in the thoracic and lumbar regions in eight cadavers. The medial branch supplied the spinalis compartment, and reached the skin. The lateral branch supplied the iliocostalis muscle compartment, and reached skin. The intermediate branch supplied the longissimus muscle and the area between the medial and the lateral branch, which was a seemingly shorter branch. CONCLUSION: The triplication of the primary branch of the PRSN is considered not uncommon. The third branch should be recognized in the literature and in textbooks.

Expression of the JAK/STAT signaling pathway in the ligamentum flavum of patients with lumbar spinal canal stenosis.

BACKGROUND: Ligamentum flavum (LF) hypertrophy is an important cause of lumbar spinal canal stenosis (LSS), one of the most common spinal disorders in the elderly. Although many cytokines are reported to be associated with LF hypertrophy, the intracellular signaling system is rarely discussed. The purpose of this study was to identify the JAK/STAT signaling pathway and to examine the role of the JAK/STAT systems in the hypertrophied LF. METHODS: The LF of 10 LSS patients was analyzed and the expression of JAK1, STAT3, phosphorylated (p)-STAT3, and actin was examined by Western blot analysis. The expression of p-STAT3 was also examined by immunostaining and its positive cell ratio was compared between LSS and non-LSS samples. We measured the thickness of the LF on magnetic resonance images and studied the relationship between its thickness and the expression of p-STAT3. RESULTS: JAK1, STAT3, and p-STAT3 were detected in almost all samples by Western blot analysis. Immunoreactivity against p-STAT3 was observed mainly in endothelial- and fibroblast-like cells. The expression of p-STAT3 was significantly higher in LSS than non-LSS samples; it was significantly stronger on the dorsal than the dural side of the LF and positively correlated with the thickness of the LF on the dorsal side. CONCLUSIONS: The JAK/STAT signaling pathway is positively correlated with the thickness of the LF. Our findings suggest that JAK1 and STAT3 molecules are involved in and regulate LF hypertrophy.

[Multi-Layered Closure of Transorbital Penetrating Brain Injury without Bone Reconstruction: A Case Report].

A 26-year-old man was injured in a motor vehicle accident. He sustained a compound orbital fracture with brain contusion. The brain tissue protruded through the orbit. Computed tomography showed a long contusion with a moderate amount of hematoma in the right frontal lobe. No foreign body was observed in the cranium. On 3D CTA, the major cerebral vessels were found to be intact. An urgent surgery was first performed by neurosurgeons and subsequently by ophthalmologists. The periosteum was left on the skull. A frontal periosteal, a right temporal fascial, and a right temporal muscular flap were prepared. After debridement and irrigation, the dural tear was closed with the right periosteal and fascial flaps. Finally, the frontal fascia was used to cover the orbital defect. The patient's clinical course was favorable. The patient was able to walk when discharged 46 days after the surgery. A penetrating brain injury through the orbit is rare, and its treatment is not established. A key to successful management of this injury is immediate assessment. Foreign bodies in the cranium, especially metal, should be checked for immediately. The cerebral vessels should also be evaluated. Usually, a surgical intervention is necessary. Since bone reconstruction can be associated with a risk of infection, a multi-layered closure, as described in this report, could prevent leakage of cerebrospinal fluid and subsequent meningitis.

Chordomas of the skull base and cervical spine: clinical outcomes associated with a multimodal surgical resection combined with proton-beam radiation in 40 patients.

Previous studies of chordoma have focused on either surgery, radiotherapy, or particular tumor locations. This paper reviewed the outcomes of surgery and proton radiotherapy with various tumor locations. Between 2001 and 2008, 40 patients with chordomas of the skull base and cervical spine had surgery at our hospital. Most patients received proton therapy. Their clinical course was reviewed. Age, sex, tumor location, timing of surgery, extent of resection, and chondroid appearance were evaluated in regard to the progression-free survival (PFS) and overall survival (OS). The primary surgery (PS) group was analyzed independently. The extensive resection rate was 42.5%. Permanent neurological morbidity was seen in 3.8%. Radiotherapy was performed in 75% and the mean dose was 68.9 cobalt gray equivalents. The median follow-up was 56.5 months. The 5-year PFS and OS rates were 70% and 83.4%, respectively. Metastasis was seen in 12.5%. The tumor location at the cranio-cervical junction (CCJ) was associated with a lower PFS (P = 0.007). In the PS group, a younger age and the CCJ location were related to a lower PFS (P = 0.008 and P < 0.001, respectively). The CCJ location was also related to a lower OS (P = 0.043) and it was more common in young patients (P = 0.002). Among the survivors, the median of the last Karnofsky Performance Scale score was 80 with 25.7% of patients experiencing an increase and 11.4% experiencing a decrease. Multimodal surgery and proton therapy thus improved the chordoma treatment. The CCJ location and a younger age are risks for disease progression.

Transvertebral anterior key hole foraminotomy without fusion for the cervicothoracic junction.

BACKGROUND: Various surgical procedures have been used to repair disc herniations and osteophytes at the cervicothoracic junction. Among these procedures, transvertebral anterior foraminotomy without fusion is a relatively less invasive, safe and useful method, although the majority of spinal surgeons remain unfamiliar with this method. We describe the surgical procedure for a transvertebral anterior keyhole foraminotomy without fusion at the cervicothoracic junction, and we assess the middle-term clinical and radiological outcomes. METHODS: Of 118 patients undergoing this surgery in our institute between 2007 and 2010, five (4.2 %) had C8 radiculopathy causing C7/T1 disc herniations or osteophytes. We studied five patients who underwent trans-C7 vertebral keyhole foraminotomy without fusion. We retrospectively examined clinical data, pre- and postoperative neurological status. RESULTS: In all cases, surgical decompression was successfully achieved without difficulty when accessing the pathology. No complications related to the surgical procedure were reported. The follow-up period was 12-28 (mean 20) months. In all patients, the visual analogue scale (VAS) due to radicular pain immediately decreased after the operation and did not increase thereafter. The mean VAS decreased from 7.8 (4.5-9.6) to 1.0 (0-2.1). The Cobb angle at C2-T1 in a neutral position improved from -12.6 (-2.8 to -24.7) degrees to -6.9 (4.2 to -25.4). The postoperative C7/T1 disc height decreased from 5.4 to 4.9 mm, indicating minimal loss. CONCLUSIONS: This procedure allows for direct access to the pathology and is less invasive. In this study, we clarified that this technique yields excellent radiological and clinical outcomes.

A spinal epidural hematoma with symptoms mimicking cerebral stroke.

A spontaneous cervical epidural hematoma (SCEH) is a rare condition, which usually requires urgent treatment. However, unusual manifestations, such as hemiparesis, may lead to a misdiagnosis. We herein report a case of SCEH that presented with pure motor hemiparesis to discuss the appropriate and prompt diagnosis and treatment of such cases. An 84-year-old female was brought to our emergency department complaining of nuchal pain, followed by right hemiparesis. A contrast-enhanced computed tomography (CT) scan of the neck demonstrated a spinal epidural hematoma right posterolateral to the spinal cord, extending from C2 to C3. She was managed conservatively and her symptoms improved significantly. The authors emphasize that cervical spinal lesions should be considered in the differential diagnosis for patients with acute onset of hemiparesis, when they are associated with neck pain. Even though magnetic resonance imaging is the gold standard, a CT scan is also useful for quick screening for SCEH.

[Surgical method for lumbar foraminal stenosis].

OBJECTIVE: There are mainly two surgical methods for lumbar foraminal stenosis, simple decompression of the extra-foraminal portion or decompression with fixation surgery. However the indication of either method is controversial. The aim of this study is to show our surgical method and results. METHOD: In six cases diagnosed as lumbar foraminal stenosis with or without far lateral disc herniation by X-ray, CTscan, MRI and nerve conduction velocity, decompression surgery was performed by our paramedian method (Wiltse approach). The apex and lateral portion of the superior articular facet (one third to one fourth) and the transforaminal ligament without fixation for lumbar foraminal stenosis. All patients were followed up for more than 10 months after the surgery. Japanese Orthopaedic Association (JOA) score and Visual Analogue Scale (VAS) were assessed before surgery and more than 10 months after the surgery. Postoperative radiological assessments were examined by neutral, flexion and extension X-ray. RESULT: Foraminal stenosis was successfully decompressed in all cases. The postoperative JOA score and VAS were significantly improved in comparison to the preoperative score (Recovery Rate ware of 74.9% and 85.8%). There was no recurrence of symptoms or necessity for secondary surgery. The radiological evaluation did not indicate significant instability or decrease in the disc height. CONCLUSION: Our surgical method, removing the apex and lateral part of the superior articular process and transforaminal ligament without fusion led to a good outcome and recurrence 10 months after the surgery had not occurred.

Activation of STAT1 in neurons following spinal cord injury in mice.

The signal transducer and activator of transcription 1 (STAT1) has been reported to be associated with neuronal cell death after cerebral ischemia. On the contrary, STAT3 has been revealed to regulate cell survival. We examined the chronological alteration and cellular localization of phosphorylated (p)-JAK1, p-STAT1 and p-STAT3 following mild spinal cord injury (SCI) in mice. Western blot analysis indicated that JAK1 is significantly phosphorylated, accompanied by the phosphorylation of STAT1 at Tyr(701) within a similar timeframe. Immunofluorescence staining indicated that signal transduction of STAT3 is introduced into the nucleus of the neurons within the anterior horns; however, in mirror sections, that of STAT1 is limited to the cytoplasm. These findings suggest that STAT3 signal is predominantly transduced into the nucleus and plays a stronger role in neuronal survival than STAT1. Modulation of the functional balance between STAT1 and STAT3 might determine the survival or death of neurons after SCI.

Endoscopic endonasal extreme far-medial approach for a lower clivus osteochondroma in a patient with hereditary multiple exostoses: illustrative case.

BACKGROUND: The authors reported on the use of endoscopic endonasal surgery (EES) for clivus osteochondroma in a patient with hereditary multiple exostoses (HME), a rare pediatric disorder characterized by the formation of osteochondromas adjacent to the growth plates of the axial and appendicular skeletal elements. OBSERVATIONS: A 26-year-old man with a family history of HME reported progressive hoarseness and dysphagia over the previous 6 months. He was referred to us after magnetic resonance imaging (MRI) showed a bone tumor in the lower clivus. MRI revealed tumor proliferation in the lower clivus and its extension to the bilateral occipital condyle and jugular tubercle. The hypoglossal canal and jugular foramen were encased on the right side, whereas the medulla oblongata was compressed. The tumor was subtotally resected with EES, and the brainstem was successfully decompressed. The pathological diagnosis was exostoses. Transient postoperative worsening of dysphagia improved within 1 month without other neurological deficits. The patient underwent posterior occipitoaxial fixation 3 months after EES to correct instability and local lateral tilt of the right atlanto-occipital joint. LESSONS: The authors' experience showed that EES is effective for resection of lower clivus osteochondromas, including the cartilaginous cap, and may improve clinical outcomes in patients with HME.

Disseminated neurenteric cyst.

This case report presents the unusual holospinal dissemination of a neurenteric cyst, which was successfully treated by fenestration and placement of a subarachnoid-peritoneal (SP) shunt. The patient was a 46-year-old Japanese woman with a history of fourth ventricle neurenteric cysts, which were managed with cyst fenestration in 1996 and 2005. She had been doing well until January 2006, when she developed dizziness and an unsteady gait. A neurological examination revealed a disturbance in the deep sensation of the feet. A neuroimaging evaluation demonstrated multiple cystic lesions in the whole spinal canal, which significantly distorted the spinal cord. Because the spinal cord distortion was the most severe in the lower cervical to upper thoracic areas, a unilateral osteoplastic laminotomy with an endoscopic cyst fenestration was performed in these areas, followed by placement of an SP shunt. The pathological diagnosis was a disseminated neurenteric cyst. There was no malignancy, and the patient has been well, with an improved gait and no signs of peritoneal dissemination, for > 1 year. The present case showed a unique extent of dissemination, which was most likely a secondary characteristic. Neurenteric cysts are well known for their tendency to recur, and total removal is usually difficult because of adhesion of the cyst membrane to important structures. The lesion also compromises cerebrospinal fluid circulation. Cyst fenestration combined with SP shunt placement might be a treatment option in such a case.

Posterior inferior cerebellar artery with an extradural origin from the V3 segment: higher incidence on the nondominant vertebral artery.

OBJECTIVE The posterior inferior cerebellar artery (PICA) and the vertebral artery (VA) often exhibit anatomical variations at the craniovertebral junction (CVJ). An example of this is the PICA originating extradurally from the V3 segment of the VA. To date, some cadaveric investigations have been reported, but the incidence and relationship of this variation to the VA and the atlas as observed on clinical imaging have not been discussed. This study evaluated the prevalence of PICAs originating from the V3 on CT scanning. Other variations of the atlas and VA were also analyzed. METHODS CT images from a series of 153 patients who underwent 3D CT angiography (CTA) were analyzed, and variations of the PICA, VA, and atlas were investigated. RESULTS A total of 142 patients (284 sides) were analyzed; 11 patients (7.2%) were excluded due to poor image quality. The most common VA variation was the PICA originating from V3 (9.5% of 284 sides), which was more frequently observed on the nondominant VA than the dominant VA (22.5% vs 6.25%, p = 0.0005). A VA with a PICA end was identified in 4 sides (1.4%), which is the same incidence as observed in the persistent first intersegmental VA (1.4%). VA fenestration was only found in 1 side (0.35%). Regarding the atlas, ponticulus posticus was observed in 24 sides (8.5%). There was no relationship between the incidence of ponticulus posticus and the variations of the VA. CONCLUSIONS A PICA originating from V3 was the most common VA variation at the CVJ and was more common on the nondominant VA. Three-dimensional CTA is useful for the evaluation of this variance. Surgeons should be mindful of this variation during operations.

Improved Vision from Severe Compressive Optic Neuropathy by Apical Cavernous Hemangioma.

A 59-year-old woman had a 1-year history of right vision loss. Her visual acuity was then 0.01 OD, and the critical flicker frequency (CFF) was 8 Hz OD. Goldmann perimetry examination showed inferior suppression of the right visual field center. Funduscopic examination revealed normal coloring of the right optic disc. Imaging studies showed an apical oval tumor. The optic nerve was compressed by both the tumor and the superior rectus muscle/levator palpebrae superioris complex. The tumor was dissected from the surrounding tissues and completely extracted. Histopathologic examination confirmed a cavernous hemangioma. The patient underwent three cycles of postoperative steroid pulse therapy. One year after the surgery, her visual acuity and CFF improved to 1.0 and 32 Hz OD, respectively. Her right visual field was within the normal range.

Exploitation of Simple Classification and Space Created by the Tumor for the Treatment of Foramen Magnum Meningiomas.

OBJECTIVE: The resection of foramen magnum meningiomas (FMMs) presents neurosurgical challenges. We propose a simple classification of the tumor location and the operating space created by the tumor to help treatment planning. METHODS: We retrospectively analyzed 16 FMMs and divided them into 3 groups based on the tumor location--clival, foraminal, and atlantal tumors. The distance between the condyle and the neuraxis at the level of the foramen magnum was measured and defined as the available operative space (AOS). We also reviewed intraoperative video recordings to assess the surgical exposure of the tumor by the space created by the FMM and compared it with the AOS. RESULTS: There were 4 clival, 8 foraminal, and 4 atlantal tumors. The AOS of the clival tumors was 10 mm ± 1.7, the AOS of the foraminal tumors was 18 mm ± 3.7, and the AOS of the atlantal tumors was 12 mm ± 2.1. All foraminal and atlantal tumors could be detached without a brain retractor. Because a major portion of the clival tumors was covered by the spinomedullary junction, a brain spatula was needed to obtain the required surgical space. The difference in AOS between clival and foraminal/atlantal tumors was statistically significant (P = 0.044). Although 4 patients experienced postoperative complications, the average postoperative Karnofsky performance scale score improved. The surgical complication rate was significantly lower in foraminal and atlantal FMMs than in clival FMMs (P = 0.027). CONCLUSIONS: The simple classification of the tumor location helped to assess surgical difficulties. Knowledge of the space created by the FMMs between the condyle and the neuraxis is useful for planning the approach strategy, especially for estimating the available working space without resection of the occipital condyle.

Pitfalls in the Management of Atlanto-Occipital Dislocation.

Atlanto-occipital dislocation (AOD) is rarely seen in clinic because it is characteristically immediately fatal. With recent progress in the pre-hospital care, an increasing number of AOD survivors have been reported. However, because the pathophysiology of AOD is not clearly understood yet, the appropriate strategy for the initial management remains still unclear. We report a case of successful AOD treatment and describe important points in the management of this condition. It is important to note that abducens nerve palsy is a warning sign of AOD and that AOD can result in a life-threatening distortion of the arteries and the brain stem. We recommend the application of a halo vest to protect the patient's neural and vascular competence as the immediate initial step in the treatment of AOD. Horn's grading system is useful in assessing indications for surgery. Finally, when performing posterior fixation, C2 should be included because of the anatomy of the ligamentous architecture.

Head and neck extension-fixation with a head frame for exposure of the distal internal carotid artery in carotid endarterectomy--technical note.

Adequate exposure of the distal internal carotid artery (ICA) for carotid endarterectomy may be difficult to achieve because of the position of the mandible and associated soft tissues. A simple yet effective use of a head frame is described to gain several centimeters of exposure of the distal ICA. The patient's head and neck are fixed in an extension position using a radiolucent head frame. Nasotracheal intubation and secure taping of the chin are also employed to keep the mouth closed and to prevent the mandible from spontaneously hanging down. The head frame tightly fixes the patient's neck, so the mandible does not disturb the surgical field throughout the operation. This simple method maximizes exposure of the distal ICA. The radiolucent head frame also enables intraoperative angiography to confirm the patency of the ICA and the absence of flap formation. This simple technique is useful for exposing the distal ICA.

Trumpet laminectomy microdecompression for lumbal canal stenosis.

Microsurgery techniques are useful innovations towards minimizing the insult of canal stenosis. Here, we describe the trumpet laminectomy microdecompression (TLM) technique, advantages and disadvantages. Sixty-two TLM patients with lumbar disc herniation, facet hypertrophy or yellow ligament or intracanal granulation tissue. The symptoms are low back pain, dysesthesia and severe pain on both legs. Spine levels operated Th11-S1; the patients who had trumpet-type fenestration, 62.9% had hypertrophy of the facet joint, 11.3% had intracanal granulation tissue, 79.1% had hypertrophy of the yellow ligament and 64.5% had disc herniation. The average of procedure duration was 68.9 min and intraoperative blood loss was 47.4 mL. Intraoperative complications were found in 3.2% of patients, with dural damage but without cerebrospinal fluid leakage. The TLM can be performed for all ages and all levels of spinal canal stenosis, without the complication of spondilolistesis. The TLM has a shorter duration, with minimal intraoperative blood loss.

Long-term progressive deterioration of visual function after papilledema improved by embolization of a dural arteriovenous fistula in the sigmoid sinus: a case report.

INTRODUCTION: It is generally believed that people affected by papilledema will not have progressive damage to their eyesight if they receive adequate medical care to treat the underlying cause of the papilledema. We present a case that appears to contradict this widely accepted belief. CASE PRESENTATION: A 53-year-old Japanese man with tinnitus visited our hospital. His initial best-corrected visual acuity in either eye was not impaired, although they both exhibited papilledema. Magnetic resonance imaging did not reveal a mass or hemorrhagic lesion in our patient's brain. Nevertheless, his best-corrected visual acuity gradually deteriorated over the following three months. Angiography demonstrated a dural arteriovenous fistula in his sigmoid sinus. After embolization therapy, the papilledema improved in both eyes. However, over the subsequent four years, his best-corrected visual acuity progressively deteriorated due to an unknown cause, despite the successful embolization of the dural arteriovenous fistula. CONCLUSION: There may be delayed onset of an unknown pathophysiology in the visual system after treatment for the underlying cause of papilledema, implying an uncertain visual prognosis for patients with this condition.

Expression of the JAK/STAT3/SOCS3 signaling pathway in herniated lumbar discs.

The inflammatory cytokine interleukin-6 (IL-6) plays an important role in causing symptoms of lumbar disk herniation. The present study clarifies the expression of the signaling pathway of IL-6 in herniated discs. Homogenates prepared from lumbar herniated discs from 10 patients were assessed. The expression of janus kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), phosphorylated (p)-STAT3 at Tyr(705), suppressor of cytokine signaling 3 (SOCS3) and actin was examined by Western blot analysis. The expression of JAK1, STAT3, and p-STAT3 at Tyr(705) was also examined by immunostaining. JAK1, STAT3, p-STAT3 at Tyr(705) and SOCS3 were detected in almost all cases. Immunoreactivity against JAK1 and STAT3 was observed mainly in chondrocytes, whereas immunoreactivity against p-STAT3 at Tyr(705) was observed in the nuclei of chondrocytes. The JAK/STAT signaling pathway might be activated by IL-6 and transmit messages from the cell surface to the nucleus, and the pathway is negatively regulated by SOCS3. These JAK1, STAT3 and SOCS3 molecules might tightly regulate and play a role in the degeneration of chondrocytes within herniated discs.