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OBJECTIVEEndoscopic resection of pituitary adenomas has been reported to improve vision function in up to 80%–90% of patients with visual impairment due to these adenomas. It is unclear how these reported rates translate into improvement in visual outcomes and general health as perceived by the patients. The authors evaluated self-assessed health-related quality of life (HR-QOL) and vision-related QOL (VR-QOL) in patients before and after endoscopic resection of pituitary adenomas.METHODSThe authors prospectively collected data from 50 patients who underwent endoscopic resection of pituitary adenomas. This cohort included 32 patients (64%) with visual impairment preoperatively. Twenty-seven patients (54%) had pituitary dysfunction, including 17 (34%) with hormone-producing tumors. Patients completed the National Eye Institute Visual Functioning Questionnaire and the 36-Item Short Form Health Survey preoperatively and 6 weeks and 6 months after surgery.RESULTSPatients with preoperative visual impairment reported a significant impact of this condition on VR-QOL preoperatively, including general vision, near activities, and peripheral vision; they also noted vision-specific impacts on mental health, role difficulties, dependency, and driving. After endoscopic resection of adenomas, patients reported improvement across all these categories 6 weeks postoperatively, and this improvement was maintained by 6 months postoperatively. Patients with preoperative pituitary dysfunction, including hormone-producing tumors, perceived their general health and physical function as poorer, with some of these patients reporting improvement in perceived general health after the endoscopic surgery. All patients noted that their ability to work or perform activities of daily living was transiently reduced 6 weeks postoperatively, followed by significant improvement by 6 months after the surgery.CONCLUSIONSBoth VR-QOL and patient's perceptions of their ability to do work and perform other daily activities as a result of their physical health significantly improved by 6 months after endoscopic resection of pituitary adenoma. The use of multidimensional QOL questionnaires provides a precise assessment of perceived outcomes after endoscopic surgery.

OBJECTIVEThe goal of this study was to compare the recovery of neuronal metabolism and functional reorganization in the primary motor cortex (M1) between mild and moderate cervical spondylotic myelopathy (CSM) following surgical intervention.METHODSTwenty-eight patients with CSM underwent 3-T MRI scans that included spectroscopy and functional MRI, before surgery and 6 months postsurgery. The classification of severity was based on the modified Japanese Orthopaedic Association questionnaire. Mild and moderate myelopathy were defined by modified Japanese Orthopaedic Association scores > 12 of 18 (n = 15) and 9–12 (n = 13), respectively. Ten healthy control subjects underwent 2 MRI scans 6 months apart. Metabolite levels were measured in the M1 contralateral to the greater deficit side in patients with CSM and on both sides in the controls. Motor function was assessed using a right finger–tapping paradigm and analyzed with BrainVoyager QX.RESULTSPatients with mild CSM had a lower preoperative N-acetylaspartate to creatine (NAA/Cr) ratio compared with moderate CSM, suggesting mitochondrial dysfunction. Postsurgery, NAA/Cr in moderate CSM decreased to the levels observed in mild CSM. Preoperatively, patients with mild CSM had a larger volume of activation (VOA) in the M1 than those with moderate CSM. Postoperatively, the VOAs were comparable between the mild and moderate CSM groups and had shifted toward the primary sensory cortex.CONCLUSIONSThe NAA/Cr ratio and VOA size in the M1 can be used to discriminate between mild and moderate CSM. Postsurgery, the metabolite profile of the M1 did not recover in either group, despite significant clinical improvement. The authors proposed that metabolic impairment in the M1 may trigger the recruitment of adjacent healthy cortex to achieve functional recovery.

Ageing is associated with a decline in motor function that critically interferes with activities of daily living involving manual dexterity. Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that has been shown to enhance manual dexterity in healthy aging adults. The supplementary motor area (SMA) is involved in motor preparation and bimanual control; therefore, bihemispheric tDCS incorporating the SMA may preferentially enhance bimanual motor movements in healthy older adults. The aim of the current study was to determine if tDCS incorporating SMA could improve manual dexterity in older adults. Twenty-four adults, aged 67–84 participated in this double-blind, randomized, cross over design, pilot study. One group of participants (n = 17) were randomized to receive stimulation or sham on their first visit and received the contrary on their second visit, seven days later. A second group of participants (n = 10) received three consecutive days of tDCS while performing a motor task. Participants performed unimanual and bimanual hand movements while receiving 2 mA of tDCS. The total time for participants to complete three trials of each task was recorded. No significant differences in performance times were observed between single or tri session tDCS and sham conditions. However, tDCS had opposing effects on the motor consolidation of anti-phase and in-phase bimanual tasks. During the tri session paradigm, older adults improved performance learning of antiphase bimanual movements more quickly than inphase bimanual movements, suggesting a different mechanism of action of these two movements.

© 2019 Elsevier Inc. Background: In patients with neurological disorders, a divergence can exist between patients' perceptions regarding the outcomes and the objective neurological findings. Degenerative cervical myelopathy (DCM), a prevalent condition characterized by progressive compression of the cervical spinal cord, can produce debilitating symptoms and profound neurological findings. The purpose of the present study was to determine whether the physician-derived neurological examination findings, as recorded by American Spine Injury Association (ASIA) summary score, correlated with the patient-derived outcome measures for DCM. Methods: A total of 78 patients underwent surgical management of DCM with completion of preoperative and 6-month follow-up assessments. Surgical management consisted of either anterior or posterior cervical decompression. All patients underwent a neurological evaluation, including an ASIA assessment before surgery and 6 months after surgery, and completed the modified Japanese Orthopaedic Association (mJOA), neck disability index (NDI), and Short-Form 36-item (SF-36) scales pre- and postoperatively to measure both disease-specific and general perceived outcomes. Results: The objective physician-derived neurological testing (ASIA) did not correlate with the patient-derived scales (mJOA, NDI, and SF-36) pre- or postoperatively. Patients reported significant improvements (P < 0.001) at 6 months postoperatively in extremity functioning (mJOA), neck pain (NDI), overall physical health (SF-36), and objective strength and sensory functioning (ASIA). All patient-perceived outcome measures correlated with each other pre- and postoperatively (P < 0.01). Conclusions: Objective scoring of postoperative neurological function did not correlate with patient-perceived outcomes before and after surgery for DCM. Traditional testing of motor and sensory function as part of the neurological assessment may not be sensitive enough to assess the scope of neurological changes experienced by patients with DCM.

Purpose: To characterize longitudinal metabolite alterations in the motor cortex of patients with cervical spondylotic myelopathy (CSM) by using proton magnetic resonance (MR) spectroscopy and to evaluate white matter integrity with diffusion-Tensor imaging in patients who are recovering neurologic function after decompression surgery. Materials and Methods: Informed written consent was obtained for all procedures and the study was approved by Western University's Health Sciences Research Ethics Board. Twentyeight patients with CSM and 10 healthy control subjects were prospectively recruited and underwent two separate 3-T MR imaging examinations 6 months apart. Patients with CSM underwent surgery after the first examination. N-Acetylaspartate (NAA), an indicator of neuronal mitochondrial function, normalized to creatine (Cr) levels were measured from the motor cortex contralateral to the greater functional deficit side in the patient group and on both sides in the control group. Fractional anisotropy and mean diffusivity were measured by means of diffusiontensor imaging in the white matter adjacent to the motor and sensory cortices of the hand and the entire cerebral white matter. Clinical data were analyzed by using Student t tests. Results: In patients with CSM, NAA normalized to Cr (NAA/Cr) levels were significantly lower 6 months after surgery (1.48 6 0.08; P , .03) compared with preoperative levels (1.73 6 0.09), despite significant improvement in clinical questionnaire scores. Fractional anisotropy and mean diffusivity were the same (P . .05) between the patient and control groups in all measured regions at all time points. Conclusion: NAA/Cr levels decreased in the motor cortex in patients with CSM 6 months after successful surgery. Intact white matter integrity with decreased NAA/Cr levels suggests that mitochondrial metabolic dysfunction persists after surgery. q RSNA, 2016.

OBJECTIVEThe authors used functional MRI to assess cortical reorganization of the motor network after chronic spinal cord compression and to characterize the plasticity that occurs following surgical intervention.METHODSA 3-T MRI scanner was used to acquire functional images of the brain in 22 patients with reversible cervical spinal cord compression and 10 control subjects. Controls performed a finger-tapping task on 3 different occasions (baseline, 6-week follow-up, and 6-month follow-up), whereas patients performed the identical task before surgery and again 6 weeks and 6 months after spinal decompression surgery.RESULTSAfter surgical intervention, an increased percentage blood oxygen level–dependent signal and volume of activation was observed within the contralateral and ipsilateral motor network. The volume of activation of the contralateral primary motor cortex was associated with functional measures both at baseline (r = 0.55, p < 0.01) and 6 months after surgery (r = 0.55, p < 0.01). The percentage blood oxygen level–dependent signal of the ipsilateral supplementary motor area 6 months after surgery was associated with increased function 6 months after surgery (r = 0.48, p < 0.01).CONCLUSIONSPlasticity of the contralateral and ipsilateral motor network plays complementary roles in maintaining neurological function in patients with spinal cord compression and may be critical in the recovery phase following surgery.

STUDY DESIGN This was a prospective, randomized control pilot study. OBJECTIVE The aim of this study was to determine whether continuous monitoring and adjustment of the endotracheal tube cuff pressure (ETTCP) to 15 mm Hg during ACSS would alter the incidence of postoperative dysphagia. SUMMARY OF BACKGROUND DATA Postoperative dysphagia is a recognized potential complication of anterior cervical spine surgery (ACSS). Recent findings on preventive measures suggest that certain intraoperative practices may minimize this complication. METHODS Fifty patients undergoing ACSS, arthroplasty, or fusion, completed routine lateral cervical preoperative plain films and questionnaires [Dysphagia Disability Index (DDI), Bazaz-Yoo Dysphagia Score (BYDS), and Short Form (36) Health Survey]. Patients were randomized into 2 groups: treatment group with ETTCP maintained at 15 mm Hg and control group with cuff pressure monitored without manipulation. Radiographs and questionnaires were obtained at 24 hours, 6 weeks, and 3 and 6 months postsurgery to assess soft tissue thickness and rates of dysphagia. RESULTS There were no significant differences between the groups in the soft tissue thickness or questionnaire scores at any timepoint (P>0.05). Within-group analysis revealed treatment and control groups had a significantly higher 24-hour postoperative soft tissue thickness and questionnaire scores compared with follow-up measurements (P

OBJECTIVE Cervical spondylotic myelopathy (CSM) is the most common cause of reversible spinal cord dysfunction in people over the age of 55 years. Following surgery for symptomatic CSM, patients demonstrate motor improvement early in the postoperative course, whereas sensory improvement can lag behind. The authors of the present study hypothesized that changes in the concentration of N-acetylaspartate (NAA) in the motor and sensory cortices in the brain would emulate the time course of neurological recovery following decompression surgery for CSM. Their aim was to compare and contrast how metabolite levels in the motor and sensory cortices change after surgery to reverse downstream spinal cord compression. METHODS Twenty-four patients with CSM and 8 control subjects were studied using proton MR spectroscopy (1H-MRS) images acquired on a 3.0-T Siemens MRI unit. The 1H-MRS data (TE 135 msec, TR 2000 msec) were acquired to measure absolute levels of NAA from the motor and sensory cortices in the cerebral hemisphere contralateral to the side of greater deficit at baseline in each subject. Data were also acquired at 6 weeks and 6 months following surgery. Control subjects were also evaluated at 6 weeks and 6 months following baseline data acquisition. Neurological function was measured in each subject at all time points using the Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA) questionnaire, and the American Spinal Injury Association (ASIA) neurological classification. RESULTS In the motor cortex of patients, NAA levels decreased significantly (p < 0.05) at 6 weeks and 6 months postsurgery compared with baseline levels. In the sensory cortex of patients, NAA levels decreased significantly (p < 0.05) only at 6 months after surgery compared with baseline and 6-week levels. No significant changes in NAA were found in control subjects. Clinical scores demonstrated significant (p < 0.05) motor recovery by 6 weeks, whereas sensory improvements (p < 0.05) appeared at only 6 months. CONCLUSIONS Findings suggest that metabolite changes in both the motor and sensory cortices mimic the time course of functional motor and sensory recovery in patients with CSM. The temporal course of neurological recovery may be influenced by metabolic changes in respective cortical regions.

ObjectiveTo analyze MRI characteristics of lumbar facet synovial cysts and distinguish those requiring subsequent surgical management for recurrence, after percutaneous synovial cyst rupture.Methods and materialsRetrospective chart review conducted in patients undergoing percutaneous synovial cyst rupture between February 2012 and April 2015. Pre- and post-percutaneous rupture procedure MRI spine studies were serially reviewed. Synovial cyst sizes, T1 and T2 signal characteristics and changes therein, T2 hypointense (or ‘dark rim’) thickness and change, and changes in the complexity of cyst signals were compared. Operative notes for patients who underwent subsequent surgical removal of recurrent synovial cysts were reviewed.Results24 patients received 41 percutaneous synovial cyst rupture procedures, with a technical success rate of 82.9%. There was a significant difference in the mean increased thickness of the T2 hypointense rim on the first post-rupture MRI scan (p=0.0411) between patients requiring subsequent surgery and those who did not. There was a significant difference in the average sizes of synovial cysts before the procedure (p=0.0483) in those requiring subsequent surgery and those who did not. Five complications were noted (12.2%), mostly involving leg pain or weakness. Of the nine patients who underwent subsequent surgery post-synovial cyst rupture, six of the surgeries had recorded difficulty pertaining to scarring and/or adherence of the cyst to dura.ConclusionsA larger increase in thickness of the T2 hypointense rim on the first post-rupture MRI scan and a larger synovial cyst size were associated with the need for subsequent surgical resection.

Background:Spontaneous intracranial hypotension (SIH) is an increasingly described entity, with over 70 cases reported in the literature. The classic triad includes orthostatic headache, diffuse pachymeningeal enhancement on magnetic resonance imaging (MRI) with gadolinium, and low cerebrospinal fluid pressure (CSF) in the lateral decubitus (2O) and sitting positions.Method:We present four rare clinical presentations of SIH, two of which have not been previously described in the literature, to the best of our knowledge.Results:Patient 1 presented with dyspnea, dysphagia, bilateral ptosis, diplopia and seizures. Patient 2 presented with a paradoxical positional pattern of orthostatic hypotension. In Patient 3, bilateral subdural hematomas (SDH) were encountered; while in Patient 4, a recurrent unilateral SDH requiring multiple surgical interventions was demonstrated.Conclusion:Although uncommon clinical presentations, all four cases of intracranial hypotension were spontaneous, demonstrated diagnostic MRI findings, and responded favorably to blood patches or saline injections.

Objectives:To describe the tumor characteristics and visual function in conservatively managed patients with non-functioning pituitary macroadenoma (NFMA) that contacted/compressed the visual pathway.Design:Retrospective case-series.Setting:Tertiary-care academic institution.Participants:Six patients with diagnosis of NFMA.Main Outcome:Visual function and radiological characteristics of the optic apparatus and pituitary tumor.Results:All patients had radiological evidence of optic apparatus compression but only one had visual field defect at the initial presentation. While two of the six patients developed visual field changes during follow-up (41±34.8 months), the patient with visual field defect at the time of diagnosis improved to normal vision.Conclusions:Select NFMAs that contact the optic apparatus, without visual dysfunction, may be managed with close ophthalmological and radiographic monitoring, depending on tumor and imaging characteristics. This may be of particular relevance in patients considered to have a high peri-operative risk, such as advanced age or significant co-morbidities.

Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that may modulate cortical excitability, metabolite concentration, and human behaviour. The supplementary motor area (SMA) has been largely ignored as a potential target for tDCS neurorehabilitation but is an important region in motor compensation after brain injury with strong efferent connections to the primary motor cortex (M1). The objective of this work was to measure tissue metabolite changes in the human motor cortex immediately following tDCS. We hypothesized that bihemispheric tDCS would change levels of metabolites involved in neuromodulation including N-acetylaspartate, glutamate, and creatine. In this single-blind, randomized, cross-over study, fifteen healthy adults aged 21-60 participated in two 7T MRI sessions, to identify changes in metabolite concentrations by magnetic resonance spectroscopy. Immediately after 20 minutes of tDCS, there were no significant changes in metabolite levels or metabolite ratios comparing tDCS to sham. However there was a trend toward increased NAA/tCr concentration (p=0.08) in M1 under the stimulating cathode. There was a strong, positive correlation between the change in the absolute concentration of NAA and the change in the absolute concentration of tCr (pimmediately following application of bihemispheric tDCS.

Study design Multicenter retrospective analysis. Objectives To review the results of surgical treatment during the last 6 years of C2 fractures in patients over the age of 70. Summary of background data Little information exists about the clinical outcome of surgical treatment of elderly patients with C2 fractures, their ability to return to their previous environment, and their postoperative level of independence. Methods The medical records and radiographs of 29 patients who had undergone surgical treatment for C2 fractures were reviewed. The type of C2 fracture, neurologic examination at presentation, type of surgical treatment, perioperative morbidity and mortality, presence of osseous union, and stability of alignment were recorded. Long-term disposition was determined from office visits or by telephone interview. Results Twenty-four of 29 patients had type II dens fractures alone. The remaining 5 had associated C1 fractures. All patients were neurologically intact at presentation except for 2 patients with signs and symptoms of central cord syndrome. Perioperative complications occurred in 3 patients (10.3%). One patient died on postoperative day 6 from a myocardial infarction. Mean+/-SD radiographic follow-up was 9+/-3.2 months (range, 3 to 24). Of the 16 patients who underwent odontoid screw fixation, 6 (37.5%) had osseous union, and 9 (56.2%) were stable on radiographs. An additional patient who had odontoid screw initially required a posterior approach reoperation. Of the 13 posterior fusions, 4 (30.7%) had osseous unions and 9 (69.2%) were stable on flexion extension radiographs. Mean+/-SD clinical follow-up was 18+/-2.2 months (range, 3 to 72 mo). Twenty-five of 29 patients (86.2%) returned to their previous environment. Two patients died of unrelated etiology. Conclusions C2 fractures in the elderly can be treated surgically with both anterior and posterior approaches with acceptable morbidity and mortality rates. The majority of patients can be mobilized early and return to their previous levels of independence.

Background context Cervical arthroplasty is designed to maintain cervical motion of the functional spinal unit after cervical discectomy. The impact of the ProDisc-C (Synthes Spine, Paoli, PA) on in vivo kinematics and sagittal alignment requires further assessment. Purpose The purpose of this study is to test the hypothesis that the ProDisc-C increases range of motion (ROM) in flexion and extension at the surgical level, and assess its impact on cervical alignment. Study design Clinical study. Patient sample Fifteen patients with a mean age of 49 years were included in this study. Each patient had a single-level arthroplasty. Patients with multilevel arthroplasty, previous cervical spine surgery, and length of follow-up less than 6 months were excluded from this study. Outcome measure Lateral dynamic radiographs of the cervical spine were analyzed using quantitative measurement analysis (QMA) preoperatively and postoperatively. QMA software was also used to determine the ROM and sagittal translation at the surgical level. Methods Flexion/extension lateral radiographs of the cervical spine were prospectively collected and reviewed in 15 patients preoperatively and at early (1–3 months) and late (6–14 months) follow-up after placement of the ProDisc-C. Shell angle (SA) and C2–C7 Cobb angles were measured. Sagittal translation and ROM were calculated at each time point. Preoperative values were compared with early and late follow-up values using paired Student t tests and Pearson's correlation. Results The C2–C7 Cobb angle did not change significantly after surgery. Segmental ROM increased significantly from neutral to flexion (p=.02) and neutral to extension (p=.002) at late follow-up. SA correlated significantly with ROM from neutral to extension (Pearson's r =−0.55; p=.02) and translation from neutral to extension (Pearson's r =−0.58; p=.02). Conclusions The ProDisc-C increased overall segmental ROM. A lordotic SA may be associated with restricted segmental ROM and translation in extension. This study did not detect any change in overall cervical spinal alignment after insertion of the device.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) for the management of cervical spondylosis may contribute to further degenerative changes at adjacent levels secondary to abnormal spinal motion. Insertion of a Bryan Cervical Disc (AD) (Medtronic Sofamor Danek, Memphis, TN) may prevent this accelerated degeneration. This retrospective study compares the in vivo x-ray cervical spine kinematics in patients with ACDF and AD. METHODS: Ten patients with single-level AD were matched to 10 patients with single-level ACDF based on age and sex. Lateral neutral, flexion and extension cervical x-rays were obtained preoperatively and at regular intervals up to 24 months postoperatively. Kinematic parameters, including range of motion, anteroposterior translation, and disc height, were assessed for all cervical functional spinal units using quantitative motion analysis software. Changes in these parameters were compared between matched patients from both groups using paired Student's t tests. RESULTS: The range of motion at the operated level was greater in the AD group compared with the ACDF group at early (6.9 versus 0.89 degrees, P < 0.01) and late (8.4 versus 0.53 degrees, P < 0.01) follow-up evaluations. Translation was greaterat the operated level in patients with AD at late follow-up (6.8 versus 0.8%, P< 0.03) evaluation. No significant between-group kinematic differences were seen at adjacent levels. CONCLUSION: Patients with AD and those with ACDF demonstrated similar in vivo adjacent level kinematics within the first 24 months after anterior cervical decompression.

Study Design. Prospective, randomized, controlled and double-blinded study on imaging of artificial discs. Objective. The purpose of this study is to compare postoperative imaging characteristics of the 4 currently available cervical arthroplasty devices at the level of implantation and at adjacent levels. of Background Data. Cervical arthroplasty is being performed increasingly frequently for degenerative disc disease and, in most cases, with frank neural compression. Unlike lumbar arthroplasty, performed mainly for axial back pain, decompression of neural elements may need to be confirmed with postoperative imaging after cervical arthroplasty. Methods. Preoperative and postoperative magnetic resonance imaging scans of 20 patients who had undergone cervical arthroplasty were assessed for imaging quality. Five cases each of the Bryan® (Medtronic Sofamor Danek, Memphis, TN), Prodisc-C® (Synthes Spine, Paoli, PA), Prestige LP® (Medtronic Sofamor Danek), and PCM® devices (Cervitech, Rockaway, NJ) were analyzed. Six blinded spinal surgeons scored twice sagittal and axial T2-weighted images using the Jarvik 4-point scale. Statistical analysis was performed comparing quality before surgery and after disc implantation at the operated and adjacent levels and between implant types. Results. Moderate intraobserver and interobserver reliability was noted. Preoperative images of patients in all implant groups had high-quality images at operative and adjacent levels. The Bryan and Prestige LP devices allowed satisfactory visualization of the canal, exit foramina, cord, and adjacent levels after arthroplasty. Visualization was significantly impaired in all PCM® and Prodisc-C® cases at the operated level in both the spinal canal and neural foramina. At the adjacent levels, image quality was statistically poorer in the PCM® and Prodisc-C® than those of Prestige LP® or Bryan®. Conclusions. Postoperative visualization of neural structures and adjacent levels after cervical arthroplasty is variable among current available devices. Devices containing nontitanium metals (cobalt-chrome-molybdenum alloys in the PCM® and Prodisc-C®) prevent accurate postoperative assessment with magnetic resonance imaging at the surgical and adjacent levels. Titanium devices, with or without polyethylene (Bryan® disc or Prestige LP®), allow for satisfactory monitoring of the adjacent and operated levels. This information is crucial for any surgeon who wishes to assess adequacy of neural decompression and where monitoring of adjacent levels is desired.

The early clinical results with the Bryan Cervical Disc prosthesis are encouraging but 2 recent small published series have noted postoperative radiologic kyphosis of the functional spinal unit (FSU) of 4 and 6 degrees. The current study was undertaken to accurately assess the extent of any sagittal deformity after the use of this prosthesis in a substantial, multisurgeon case series. The neutral, erect x-rays of 67 consecutive patients (88 disc levels) operated by one of 3 surgeons, were examined using manual and digital image analysis techniques for FSU sagittal angulation (lordosis), prosthesis shell angulation, segmental olisthesis, and overall cervical alignment. Measurement accuracy was confirmed using interobserver and intraobserver studies. There was a median loss of 2 degrees in FSU lordosis when compared with preoperative imaging (P

STUDY DESIGN In vitro biomechanical flexibility experiment studying 5 sequential conditions. OBJECTIVE To determine the biomechanical differences among 3 fixation techniques after a simulated hangman's fracture. SUMMARY OF BACKGROUND DATA Type II hangman's fractures are often treated surgically with a C2-C3 anterior cervical discectomy, fusion, and plating. Other techniques include direct fixation with C2 pars interarticularis screws or posterior C2-C3 fixation connecting C2 pars screws to C3 lateral mass screws. METHODS Seven cadaveric specimens (Oc-C4) were tested intact, after a simulated hangman's fracture, and after each fixation technique. Flexion, extension, lateral bending, and axial rotation were induced using nonconstraining torques while recording angular motions stereophotogrammetrically. RESULTS Direct screw fixation reduced motion an average of 61% +/- 13% during lateral bending and axial rotation compared to the injured state (P < 0.007). However, instability remained during flexion and extension. Posterior C2-C3 rod fixation provided significantly greater rigidity than anterior plate fixation during lateral bending (P < 0.008) and axial rotation (P < 0.04). CONCLUSIONS Direct fixation of the pars ineffectively limits flexion and extension after a Type II hangman's fracture. If pars screw fixation can be achieved, posterior C2-C3 fixation more effectively stabilizes a hangman's fracture than anterior cervical plating.

OBJECT The relationship between headaches, pituitary adenomas, and surgical treatment of pituitary adenomas remains unclear. The authors assessed the severity and predictors of self-reported headaches in patients referred for surgery of pituitary adenomas and evaluated the impact of endoscopic transsphenoidal surgery on headache severity and quality of life (QOL). METHODS In this prospective study, 79 patients with pituitary adenomas underwent endoscopic transsphenoidal resection and completed the Headache Impact Test (HIT-6) and the 36-Item Short Form Health Survey (SF-36) QOL questionnaire preoperatively and at 6 weeks and 6 months postoperatively. RESULTS Preoperatively, 49.4% of patients had mild headache severity, 13.9% had moderate severity, 13.9% had substantial severity, and 22.8% had intense severity. Younger age and hormone-producing tumors predisposed greater headache severity, while tumor volume, suprasellar extension, chiasmal compression, and cavernous sinus invasion of the pituitary tumors did not. Preoperative headache severity was found to be significantly associated with reduced scores across all SF-36 QOL dimensions and most significantly associated with mental health. By 6 months postoperatively, headache severity was reduced in a significant proportion of patients. Of the 40 patients with headaches causing an impact on daily living (moderate, substantial, or intense headache), 70% had improvement of at least 1 category on HIT-6 by 6 months postoperatively, while headache worsened in 7.6% of patients. The best predictors of headache response to surgery included younger age, poor preoperative SF-36 mental health score, and hormone-producing microadenoma. CONCLUSIONS The results of this study confirm that surgery can significantly improve headaches in patients with pituitary adenomas by 6 months postoperatively, particularly in younger patients whose preoperative QOL is impacted. A larger multicenter study is underway to evaluate the long-term effect of surgery on headaches in this patient group.

STUDY DESIGN: Retrospective review. OBJECTIVE: To describe the incidence, clinical features, and treatment of traumatic spinal cord injury (SCI) treated at a Canadian tertiary care center. SUMMARY OF BACKGROUND DATA: Understanding the current epidemiology of acute traumatic SCI is essential for public resource allocation and primary prevention. Recent reports suggest that the mean age of patients with SCI may be increasing. METHODS: We retrospectively reviewed hospital records on all patients with traumatic SCI between January 1997 and June 2001 (n = 151). Variables assessed included age, gender, length of hospitalization, type and mechanism of injury, associated spinal fractures, neurologic deficit, and treatment. RESULTS: Annual age-adjusted incidence rates were 42.4 per million for adults aged 15-64 years, and 51.4 per million for those 65 years and older. Motor vehicle accidents accounted for 35% of SCI. Falls were responsible for 63% of SCI among patients older than 65 years and for 31% of injuries overall. Cervical SCI was most common, particularly in the elderly, and was associated with fracture in only 56% of cases. Thoracic and lumbar SCI were associated with spinal fractures in 100% and 85% of cases, respectively. In-hospital mortality was 8%. Mortality was significantly higher among the elderly. Treatment of thoracic and lumbar fractures associated with SCI was predominantly surgical, whereas cervical fractures were equally likely to be treated with external immobilization alone or with surgery. CONCLUSION: A large proportion of injuries was seen among older adults, predominantly as a result of falls. Prevention programs should expand their focus to include home safety and avoidance of falls in the elderly. Language: en

Object. The potential role of cervical arthroplasty in patients who have undergone previous cervical surgery is unknown. The authors performed a prospective study involving nonrandomized clinical and radiological assessment in patients who had undergone either previous posterior cervical foraminotomy or anterior interbody fusion and who suffered new or persistent arm/neck symptoms related to neural compression. Methods. During a 30-month period, 15 patients who had previously undergone cervical spinal surgery underwent cervical arthroplasty that involved placement of the Bryan disc for neck or arm symptoms related to cervical disc disease. A total of 24 devices were implanted. Six of the 15 patients had undergone a previous posterior foraminotomy, and in nine cases an anterior interbody fusion had been perfomed at some stage prior to surgery. Clinical and radiological evaluations were performed preoperatively and after surgery to assess outcomes. A total of 24 arthroplasties were performed encompassing between one and three levels. There were no major perioperative complications or immediate device-related failures. Two patients were lost to follow up. The follow-up period ranged from 12 to 43 months (mean 24.2 ± 10.5 months). Good results were obtained in all cases as reflected by an increase in the visual analog scale score of 6.4 in terms of neck/arm pain (p < 0.05). There was no difference in Oswestry Disability Index scores for neck pain (p > 0.05) and no patient required surgery at the same level. In one patient hypermobility developed with internal subluxation of the device, which suggested a compromise adjacent to a two-level fusion at 21 months. The segment was hypermobile preoperatively. The patient has experienced recurrent neck pain but otherwise remains clinically well and has not required revision surgery to date. Conclusions. Insertion of the Bryan artificial cervical disc in patients who have previously undergone cervical fusion or posterior foraminotomy, in general, appears to be safe. It provided encouraging early clinical results, although patients with preoperative hypermobility should be treated with caution. Issues such as accelerated device-related wear and the use of arthroplasty after aggressive facetectomy resection will need further study; however, in carefully selected patients who have undergone previous surgery cervical arthroplasty may provide an additional tool in the management of cervical disc disease.

STUDY DESIGN Unilateral facet dislocation was created in human cadaveric cervical spines. Specimens were sequentially instrumented with posterior or anterior screws and plates, and studied biomechanically. OBJECTIVE To determine the biomechanical differences between anterior and posterior fixation for stabilization of a reduced unilateral cervical facet dislocation. SUMMARY OF BACKGROUND DATA Although previous studies have compared anterior to posterior instrumentation, no data exist on the biomechanics of either type of stabilization after this particular injury. METHODS In 6 human cadaveric cervical spine segments, a reproducible unilateral facet dislocation was created and then unlocked (reduced). Nondestructive torques were applied to specimens that were intact, injured-reduced, fixated using posterior nonlocking lateral mass plates, and fixated using a bone graft plus an anterior nonlocking plate. Flexion, extension, lateral bending, and axial rotation were measured stereophotogrammetrically. RESULTS Lateral mass plating was more effective than anterior plating in limiting motion after reduction of a unilateral facet dislocation. Averaged, over all loading directions, lateral mass plates reduced the range of motion to 17% of normal; anterior plates reduced range of motion to 89% of normal. In all loading directions, lateral mass plates performed significantly better than anterior plates (P < 0.05, paired Student t-tests). CONCLUSIONS Anterior and posterior plating effectively stabilized a reduced unilateral facet dislocation. Lateral mass fixation provided better immobilization than anterior graft and plate.

Angiolipomas are rarely encountered in the spine. We report the case of a 47-year-old man with a thoracic angiolipoma involving the T9 vertebral body. A preoperative spinal angiogram confirmed a highly vascular neoplasm. The lesion was treated with endovascular embolization prior to a T9 corpectomy and resection of the epidural component of the tumor. At time of surgery, minimal blood loss occurred during resection of the vertebral body and the epidural mass. Pathologic examination demonstrated features consistent with spinal angiolipoma. This report emphasizes the clinical, radiographic, and pathologic features of infiltrating spinal angiolipoma and discusses therapeutic management options.

Object Spinal arthroplasty may become the next gold standard for the treatment of degenerative cervical spine disease. This new modality must be studied rigorously to ensure in vivo efficacy and safety. The authors review the preliminary clinical experience and radiographic outcomes following insertion of the Bryan Cervical Disc Prosthesis (Medtronic Sofamor Danek, Memphis, TN). Methods This prospective cohort study included 26 patients undergoing single- or two-level implantation of the Bryan artificial cervical disc for treatment of cervical degenerative disc disease resulting in radiculopathy and/or myelopathy. Radiographic and clinical assessments were made preoperatively 1.5, 3 months, and at 6, 12, and up to 24 months postoperatively. The Neck Disability Index (NDI) and Short Form–36 (SF-36) questionnaires were used to assess pain and functional outcomes. Segmental sagittal rotation from C2–3 to C6–7 was measured using quantitative motion analysis software. A total of 30 Bryan discs were placed in 26 patients. A single-level procedure was performed in 22 patients and a two-level procedure in the other four. Follow-up duration ranged from 1.5 to 27 months, with a mean duration of 12.3 months. A statistically significant improvement in the mean NDI scores was seen between pre- and late postoperative follow-up evaluations. A trend toward improvement in the SF-36 physical component was also found. Motion was preserved in the treated spinal segments (mean range of motion 7.8°) for up to 24 months postsurgery. The relative contribution of each segment to overall spinal sagittal rotation differed depending on whether the disc was placed at C5–6 or C6–7. Overall cervical motion (C2–7) was moderately increased on late follow-up evaluations. Conclusions The Bryan artificial cervical disc provided in vivo functional spinal motion at the treated level. Overall cervical spinal motion was not significantly altered. Sagittal rotation did not change significantly at any level after surgery.

Object Cervical arthroplasty offers the promise of maintaining motion of the functional spinal unit (FSU) after anterior cervical discectomy. The impact of cervical arthroplasty on sagittal alignment of the FSU needs to be addressed, together with its effect on overall sagittal balance of the cervical spine. Methods The authors prospectively reviewed radiographic and clinical outcomes in 14 patients who received the Bryan Cervical Disc prosthesis (Medtronic Sofamor Danek, Memphis, TN), for whom early (< 6 months) and late (6–24 months) follow-up data were available. Static and dynamic radiographs were measured by hand and computer to determine the angles formed by the endplates of the natural disc preoperatively, those formed by the shells of the implanted prosthesis, the angle of the FSU, and the C2–7 Cobb angle. The range of motion (ROM) was also determined radiographically, whereas clinical outcomes were assessed using the Neck Disability Index (NDI), and Short Form–36 (SF-36) questionnaires. The ROM was preserved following surgery, with a mean preoperative sagittal rotation angle of 8.96°, which was not significantly different from the late postoperative value of 8.25°. When compared with the preoperative disc space angle, the shell endplate angle in the neutral position became kyphotic in the early and late postoperative periods (mean change −3.8° in the late follow-up period; p = 0.0035). The FSU angles also became significantly more kyphotic post-operatively, with a mean change of −6° (p = 0.0006). The Cobb angles varied widely preoperatively and did not change significantly after surgery. There was no statistical correlation between the NDI and SF-36 outcomes and cervical kyphosis. Conclusions Cervical arthroplasty preserves motion of the FSU. Both the endplate angle of the treated disc space and the angle of the FSU became kyphotic after insertion of the Bryan prosthesis. The overall sagittal balance of the cervical spine, however, was preserved.

STUDY DESIGN: Human cadaveric cervical spines were subjected to nondestructive repeated-measures flexibility tests before, during, and after unilateral facet dislocation. OBJECTIVES: To assess the relative stability and kinematics of the spine in the normal condition, after unilateral facet lock without bony injury and after reducing (unlocking) the facet dislocation. SUMMARY OF BACKGROUND DATA: Experimental unilateral facet dislocation has been studied only when associated with extensive damage to disc, bone, or both. The relative stability of the normal, locked, and unlocked cervical spine has not been studied. METHODS: Unilateral facet dislocation with minimal associated injury was created by slowly applying axial torque while specimens were bent laterally and flexed. Before and after injury, nondestructive torques were applied about each anatomic axis, while three-dimensional specimen motion was recorded stereophotogrammetrically. RESULTS: Unilateral facet dislocation was created with a mean axial torque of 10.2 +/- 2.7 Nm. After locking, range of motion, lax zone, and stiff zone were significantly reduced relative to normal (P < 0.05). After unlocking, the same parameters were significantly increased relative to normal. The position of the axis of rotation shifted when the facet was locked and the centrode elongated after the facet was unlocked. CONCLUSIONS: Unilateral facet dislocation without fracture can be created with moderate loads when axial torque is applied while the facet is distracted. The spine is stable while the articular masses are locked unilaterally; however, the motion segment becomes overtly unstable after the facet dislocation is reduced.

It has been suggested that gangliogliomas represent a neoplastic transformation of a dysplastic focus or heterotopia. Other theories propose that gangliogliomas arise from multipotent stem cells with the ability to differentiate along glial and neuronal cell lines. Our goal was to characterize the expression of nestin, a neuroepithelial precursor/stem cell antigen, in gangliogliomas along with other pathological and clinical features of this entity. The clinical and operative features of 18 recent cases meeting the histological criteria for ganglioglioma were reviewed. The expression of nestin, microtubule-associated protein 2 (MAP2), neurofilament, and glial fibrillary acidic protein (GFAP) was assessed by immunohistochemistry and confocal scanning laser microscopy. Abundant MAP2- and nestin-positive neuronal cells were found by immunohistochemistry in all 18 gangliogliomas. GFAP staining was found in reactive and lesional astrocytes but not in cells of neuronal morphology. Confocal microscopy demonstrated colocalization of nestin and MAP2 in select neuronal cells. The true lineage of gangliogliomas remains controversial. Our findings confirm the presence of cells within these lesions that harbor a persistent stem cell cytoskeletal protein (nestin). Further insight into the cytoskeletal derangement of nestin-positive neuronal cells may shed further light on the pathogenesis of gangliogliomas and its associated epilepsy.

✓ A 29-year-old man presented in 1984 with a recent onset of partial seizures marked by speech arrest. Electroencephalography identified a left frontotemporal dysrhythmia. Computerized tomography (CT) scanning revealed a superficial hypodense nonenhancing lesion in the midleft frontal convexity, with some remodeling of the overlying skull. The patient was transferred to the London Health Sciences Centre for subtotal resection of what was diagnosed as a “fibrillary astrocytoma (microcystic).” He received no chemotherapy or radiation therapy and remained well for 11 years.The patient presented again in late 1995 with progressive seizure activity. Both CT and magnetic resonance imaging demonstrated a recurrent enhancing partly cystic lesion. A Grade IV astrocytoma was resected, and within the malignant tumor was a superficial area reminiscent of a dysembryoplastic neuroepithelial tumor (DNT). Data on the lesion that had been resected in 1984 were reviewed, and in retrospect the lesion was identified as a DNT of the complex form. It was bordered by cortical dysplasia and contained glial nodules, in addition to the specific glioneuronal element. The glial nodules were significant for moderate pleomorphism and rare mitotic figures. The Ki67 labeling index averaged 0.3% in the glial nodules and up to 4% focally. Cells were rarely Ki67 positive within the glioneuronal component. This case is the first documented example of malignant transformation of a DNT. It serves as a warning of the potential for malignant transformation in this entity, which has been traditionally accepted as benign. This warning may be especially warranted when confronted with complex forms of DNT. The completeness of resection in the benign state is of paramount importance.

During central nervous system (CNS) development, intermediate filaments are subjected to a sequential remodelling process. Nestin is a distinct intermediate filament which is transiently expressed in proliferating neuroepithelial stem cells during the neurulation stage of development. Nestin re-expression in the adult rat was studied following transient (2 h) middle cerebral artery occlusion. Seven days after the ischemic insult, nestin reactive astrocytes were found in the border zone surrounding cerebral infarction. Nestin immunoreactivity delineated a zone between infarction and the surrounding intact cerebral parenchyma. In situ hybridization for nestin mRNA showed early changes in small cells in the surround of the ischemic lesion. These results with nestin, along with other stem cell markers expressed by reactive astrocytes, suggest an embryonic reversion of the mature cytoskeleton as a response of astrocytes to cerebral injury.

Background Postoperative hyposmia and anosmia is an often overlooked complication of endoscopic pituitary surgery. Septal flaps have been utilized as a strategy for repairing and preventing postoperative cerebrospinal fluid (CSF) leaks. The olfactory impact of raising this flap for sellar reconstruction and CSF repair needs qualitative assessment. This study aims to ascertain the effect of the Hadad-Bassagasteguy (HB) flap on olfaction in endoscopic pituitary surgery. Methods In this randomized controlled trial, patients undergoing pituitary surgery underwent computerized randomization. Those in Group 1 all had HB flaps raised and placed for sellar floor defects. Those in Group 2 underwent reconstruction with synthetic or nonautologous materials. The University of Pennsylvania Smell Identification Test (UPSIT) was administered preoperatively and 6 months postoperatively. Results were analyzed using nonparametric tests. Results Twenty subjects were enrolled, 10 in each group. Eight subjects in Group 1 vs 3 in Group 2 had intraoperative CSF leak. All were repaired intraoperatively and none required additional intervention. Preoperatively, UPSIT scores were not significantly different between groups (p = 0.62). Preoperative vs postoperative comparisons were significant for a decrease in scores in both groups postoperatively (Group 1, p < 0.001; Group 2, p < 0.001). Those undergoing HB flap reconstruction had significantly worse scores postoperatively (p = 0.001). Conclusion Endoscopic pituitary surgery results in decreased olfaction with or without deploying a septal flap. However, use of the HB flap for reconstruction can worsen hyposmia at least 6 months after surgery. Olfaction should be considered when use of the HB flap is planned. © 2013 ARS–AAOA, LLC.

Alterations in motor function in cervical myelopathy secondary to degenerative disease may be due to local effects of spinal compression or distal effects related to cortical reorganization. This prospective study characterizes differences in metabolite levels in the motor cortex, specifically N-acetylaspartate, creatine, choline, myo-inositol and glutamate plus glutamine, due to alterations in cortical function in patients with reversible spinal cord compression compared with healthy controls. We hypothesized that N-acetylaspartate/creatine levels would be decreased in the motor cortex of patients with cervical myelopathy due to reduced neuronal integrity/function and myo-inositol/creatine levels would be increased due to reactive gliosis. Twenty-four patients with cervical myelopathy and 11 healthy controls underwent proton-magnetic resonance spectroscopy on a 3.0 Tesla Siemens Magnetom Tim Trio MRI. Areas of activation from functional magnetic resonance imaging scans of a finger-tapping paradigm were used to localize a voxel on the side of greater motor deficit in the myelopathy group (n = 10 on right side and n = 14 on left side of the brain) and on each side of the motor cortex in controls. Neurological function was measured with the Neck Disability Index, modified Japanese Orthopaedic Association and American Spinal Injury Association questionnaires. Metabolite levels were measured relative to total creatine within the voxel of interest. No metabolite differences were detected between the right side and left side of the motor cortex in controls. The myelopathy group had significantly decreased neurological function compared with the control group (Neck Disability Index: P

Background context Cervical arthroplasty theoretically reduces the risk of adjacent level disc degeneration and segmental instability that may be seen after a cervical fusion. An essential argument in confirming the utility of cervical arthroplasty is long-term confirmation that cervical disc replacements can maintain physiological kinematics at the index and adjacent levels. Purpose The purpose of this in vivo prospective study was to characterize the long-term segmental kinematic outcomes after cervical arthroplasty. Study design/setting Prospective cohort study. Patient sample Twenty patients with a 5-year clinical follow-up who underwent anterior cervical discectomy with insertion of the Bryan cervical disc. Outcome measures Physiological measures (kinematic analysis of lateral neutral, flexion, and extension radiographic imaging). Methods Twenty consecutive patients with degenerative disc disease were followed with regular radiographic imaging after implantation of the Bryan cervical disc prosthesis. Lateral neutral, flexion, and extension radiographs (n=240) were analyzed using Quantitative Motion Analysis software (Medical Metrics, Inc., Houston, TX, USA) to measure the biomechanical profile at the index level and adjacent levels up to 5 years after surgery. Parameters collected included range of motion (ROM), functional spinal unit (FSU) angle, anterior and posterior disc heights, sagittal translation, and center of rotation (COR). Results Biomechanics of the implanted artificial cervical disc was maintained up to 5 years with no significant changes in ROM, FSU angle, disc height, sagittal translation, and COR values when compared with early postoperative performance. Artificial discs were able to adequately restore and maintain preoperative kinematics. Early differences seen in disc height and FSU angle did not change during the duration of follow-up. No significant kyphotic changes or decrease in ROM were seen at the adjacent spinal levels. Conclusions The Bryan cervical disc prosthesis provides for a durable solution for functional spinal motion at the operated level and maintained the preoperative kinematics at adjacent levels at the 5-year follow-up.

Cervical arthroplasty has emerged as a means of preventing adjacent segment disease by preserving motion, restoring sagittal balance, and mimicking natural spinal kinematics. The purpose of this retrospective in vivo study was to characterize the impact of arthroplasty on sagittal balance and segmental kinematics of the cervical spine.Sixty patients receiving the Bryan disc, ProDisc-C, or Prestige LP disc were retrospectively analyzed. Only single-level arthroplasty cases were included in this study. Lateral dynamic radiographs of the cervical spine were evaluated using quantitative measurement analysis software to determine the kinematics at the index level both preoperatively and 1 year postoperatively. Collected parameters included range of motion (ROM), disc angles, shell angles, anterior and posterior disc heights (ADHs/PDHs), translation, and center of rotation (COR). Preoperative and postoperative data were compared using the Student t-test, with p0.05 indicating significance.The Bryan and Prestige LP discs preserved motion, whereas the ProDisc-C increased segmental ROM from extension to flexion. Following surgery, the Bryan disc exhibited significant shell angle kyphosis, while ProDisc-C and Prestige LP retained lordosis. Both ADHs and PDHs decreased following insertion of the Bryan disc. In contrast, the ProDisc-C increased the ADHs and PDHs by 80% and 52%, respectively, and the Prestige LP disc increased the ADHs and PDHs by 20%. Only the ProDisc-C demonstrated significant translation of 0.7 mm. The ProDisc-C shifted the COR x by 0.9 mm anteriorly, while the Prestige LP disc demonstrated a significant superior shift of 2.2 mm in COR y.All discs adequately maintained ROM at the surgical level. The greatest difference among the 3 devices was in the disc height and index angle measurements.

Olfaction has been demonstrated to have a great impact on patients' lives. Transsphenoidal endoscopic pituitary surgery is associated with potentially significant damage to olfactory tissues, but to date this issue has been only poorly documented in the literature.Prospective cohort study comparing olfactory outcomes pre- and postpituitary surgery.Patients were administered the University of Pennsylvania Smell Identification Test (UPSIT) preoperatively and again at 6 months postoperatively. The endoscopic transsphenoidal pituitary surgery was carried out using a full middle turbinate preservation protocol. A Hadad-Bassagasteguy (HB) vascularized septal flap was raised in each case. Secondary outcomes included Lund-Kennedy endoscopy scores (LKES) and patient self-report of olfactory disturbance. The results were analysed using a paired t-tests.Seventeen patients met inclusion criteria for the study. Mean preoperative UPSIT value was 37.2 (normosmia), and mean postoperative UPSIT value was 30.8 (moderate hyposmia) (P.001). All patients were fully healed with normal LKES scores by 6 months. All patients complained of their olfactory dysfunction.This study is the first to describe postoperative olfactory perturbations suffered by patients undergoing endoscopic transsphenoidal pituitary surgery. We hypothesize that olfactory impairment results from use of the HB flap. We recommend that the possibility of permanent olfactory changes be added to routine patient counseling and consent for this procedure, and that HB flaps be raised judiciously during trannssphenoidal endoscopic procedures.

Study Design: A prospective study of 22 patients with single-level cervical spondylosis.Objective: To quantify the changes in the biomechanics of thecervical spine after the insertion of a ProDisc-C (Synthes Spine,Paoli, PA) artificial disc.Summary of Background Data: Cervical arthroplasty is designedto maintain cervical motion of the functional spinal unit (FSU)after cervical discectomy. The impact of the ProDisc-C on invivo kinematics and sagittal alignment requires further assess-ment.Methods: Flexion/extension lateral radiographs of the cervicalspine were prospectively collected and reviewed in 22 patientspreoperatively and after the placement of ProDisc-C. Discheight (DH), FSU angle, range of motion (ROM), and center ofrotation (COR) were calculated at each time point usingvalidated, computer-assisted methods. Preoperative values werecompared with the postoperative values using paired studentt tests.Results: Mean follow-up time was 11.0 months (SD, 2.4mo). Atthe surgical level, the ProDisc-C produced increased segmentalROM (P=0.03), an anterior shift of 1.1mm in COR X(P=0.004), and increased DH both anteriorly (P

Background and importance Spinal cord compression may induce cortical reorganization. This study follows a patient with cervical spondylotic myelopathy to investigate changes in cortical activation before and after decompressive surgery. The relationship with functional recovery is also described. Clinical presentation A 37-year-old right-hand-dominant man presented a 1-month history of rapidly worsening right-hand clumsiness, right-sided hemiparesis, and gait difficulties. Physical examination confirmed severe right-sided weakness, impaired dexterity, hyperreflexia, and wide-based gait. The patient underwent blood oxygenation level-dependent functional magnetic resonance imaging at 4 T. Images were obtained before and 6 months after an anterior cervical discectomy with insertion of an artificial disk. Blood oxygenation level-dependent functional magnetic resonance imaging was used to detect changes in cortical activation over time during a finger-tapping (motor) paradigm. Improvement in clinical function was recorded with validated clinical tools, including the Japanese Orthopedic Association scale for cervical spondylotic myelopathy, the Nurick neurological function score, and the Neck Disability Index, along with clinical examination. Conclusion After decompressive cervical spine surgery in a patient with cervical spondylotic myelopathy, functional magnetic resonance imaging detected increased cortical activation in the primary motor cortex during finger tapping. These changes occurred concomitantly with improvement in motor function. Upper- and lower-extremity motor subscores of the Japanese Orthopedic Association scale demonstrated 40% and 43% improvement, respectively. These observations suggest that cortical reorganization or recruitment may accompany the recovery of function after spinal cord injury.

OBJECTIVE: We examined the incidence of perioperative fever and its relationship to outcome among patients enrolled in the Intraoperative Hypothermia for Aneurysm Surgery Trial. METHODS: One thousand patients with initial World Federation of Neurological Surgeons grades of I to III undergoing clipping of intracranial aneurysms after subarachnoid hemorrhage were randomized to intraoperative normothermia (36 degrees C-37 degrees C) or hypothermia (32.5 degrees C-33.5 degrees C). Fever (> or =38.5 degrees C) and other complications (including infections) occurring between admission and discharge (or death) were recorded. Functional and neuropsychologic outcomes were assessed 3 months postoperatively. The primary outcome variable for the trial was dichotomized Glasgow Outcome Scale (good outcome versus all others). RESULTS: Fever was reported in 41% of patients. In 97% of these, fever occurred in the postoperative period. The median time from surgery to first fever was 3 days. All measures of outcome were worse in patients who developed fever, even in those without infections or who were World Federation of Neurological Surgeons grade I. Logistic regression analyses were performed to adjust for differences in preoperative factors (e.g., age, Fisher grade, initial neurological status). This demonstrated that fever continued to be significantly associated with most outcome measures, even when infection was added to the model. An alternative stepwise model selection process including all fever-related measures from the preoperative and intraoperative period (e.g., hydrocephalus, duration of surgery, intraoperative blood loss) resulted in the loss of significance for dichotomized Glasgow Outcome Scale, but significant associations between fever and several other outcome measures remained. After adding postoperative delayed ischemic neurological deficits to the model, only worsened National Institutes of Health Stroke Scale score, Barthel Activities of Daily Living index, and discharge destination (home versus other) remained independently associated with fever. CONCLUSION: These findings suggest that fever is associated with worsened outcome in surgical subarachnoid hemorrhage patients, although, because the association between fever and the primary outcome measure for the trial is dependent on the covariates used in the analysis (particularly operative events and delayed ischemic neurological deficits), we cannot rule out the possibility that fever is a marker for other events. Only a formal trial of fever treatment or prevention can address this issue.

Aims: Dysembryoplastic neuroepithelial tumours (DNTs) have been considered benign lesions characterised by a chronic, indolent clinical course. Previous studies have suggested that increased proliferation rates may be balanced by corresponding rates of apoptosis. The objective of this study was to determine whether a correlation exists between histological features and indices of proliferation/apoptosis. Methods: Fourteen consecutive surgical specimens meeting the histological criteria for DNT were retrospectively reviewed for evidence of aggressive histological features, including anaplasia, mitotic activity, and Ki67 labelling. Immunohistochemistry was performed semiquantitatively to evaluate and compare proliferation (Ki76) and apoptosis (TUNEL). The clinical course of the patients was also reviewed. Results: Atypical histological features were demonstrated in the glial component of select complex DNTs. TUNEL indices, however, had negligible correlation with proliferative indices. A balance between cell proliferation and apoptosis was not evident particularly in those cases displaying aggressive histological features. Conclusions: While there is no clearly defined clinical or pathological pattern to indicate aggressive growth of DNTs, elevated proliferative indices coupled with atypical histological features in complex DNTs should be taken into consideration in determining the aggressiveness of surgical extirpation and follow-up until experience with these uncommon tumours is greater.

Part 1 of the current study found that use of the Bryan Cervical Disc prosthesis resulted in a median loss of 2 degrees in functional spinal unit (FSU) lordosis when compared with preoperative imaging (P0.0001, range: 8-degree loss to 5-degree gain). The observed changes were generally small but varied among both the patients and the surgeons, suggesting that variables may exist which affect postoperative sagittal alignment. The aim of the current study was to identify which, if any, of a range of patient and surgical variables may contribute significantly to postoperative FSU malalignment. The change in FSU angulation between the preoperative and postoperative neutral, erect x-rays of 67 consecutive patients (88 disc levels) were correlated with 35 demographic and radiographic variables. Postoperative change in disc space height, angle of prosthesis insertion, and the amount of bone removed from the anterior aspect of the cephalad vertebra varied significantly among the 3 surgeons and correlated with change in FSU alignment. Intraoperative disc space distraction correlated with subsequent loss of disc space height. Multiple linear regression analysis confirmed that loss of disc space height and angle of prosthesis insertion contributed independently to a model with a coefficient of determination of 0.39 (P0.0001). Attempts to identify factors contributing to change in alignment have not shown any single factor to be wholly responsible. Although the prescribed surgical technique is relatively standardized, it seems likely that a number of surgical variables, particularly those leading to loss of disc space height and affecting annular tension are important.

Objective The Bryan disc prosthesis (Medtronic Sofamor Danek, Memphis, TN) relies on a precise fit between the device and the vertebral endplates to provide immediate stability after cervical arthroplasty. The safety of the cervical arthroplasty in the setting of trauma is unknown. We compare the segmental strength of the normal cervical spine and the cervical spine after single-level arthroplasty. Methods Fifteen cadaveric cervical spines with arthroplasty placed at the C5-C6 level were compared with 16 intact cadaveric controls. A pure moment was applied to induce flexion, extension, or axial rotation until the segment failed. Results The prosthesis provided 63, 45, and 69% of the strength of a normal spine during flexion, extension, and rotation, respectively. There were no cases of prosthesis expulsion. Conclusion After insertion of the Bryan disc, the remaining ligamentous tissues provide adequate acute stability to the spine.

Object Spinal arthroplasty is becoming more widely performed in the treatment of degenerative cervical disc disease. Although this new technology may offer benefits over arthrodesis, it also requires that the surgeon acquire new operative techniques, and new potential complications are introduced. To determine the incidence and distribution of perioperative complications, the authors analyzed their early data obtained in a series of patients treated with the Bryan Cervical Disc prosthesis. Methods The authors prospectively recorded operative data, complications, and clinical and radiographic outcome data in all patients treated with Bryan prosthesis–based arthroplasty at two tertiary care centers since 2001. Patients underwent standard anterior cervical discectomy followed by one- to three-level arthroplasty. Ninety-six discs were implanted in 74 patients. The perioperative complication rate was 6.2% per treated level. In one patient a retropharyngeal hematoma developed, requiring evacuation. Neurological worsening occurred in three patients. Intraoperative migration of the prosthesis was observed in one two-level case, whereas delayed migration occurred in one patient with postoperative segmental kyphosis. In another patient with severe postoperative segmental kyphosis, revision was required with a customized lordotic prosthesis. Heterotopic ossification and spontaneous fusion occurred in two cases; motion was preserved in the remaining 94 prostheses. Partial dislocation of the prosthesis in extension occurred in one patient with preoperative segmental hypermobility, the first reported failure of a Bryan prosthesis. Twenty-five percent of patients reported neck and shoulder pain during the late follow-up period. There was a trend toward increased kyphosis of the C2–7 curvature postoperatively. Conclusions The Bryan prosthesis was effective in maintaining spinal motion. Major perioperative and device-related complications were infrequent.

This article focuses on the clinical results of three prostheses (the Bryan Cervical Disc, the Bristol Disc, and the ProDisc-C) for cervical total disc replacement. Background on the development, design, and biomechanical characteristics of each prosthesis is given and surgical indications and clinical results are summarized and analyzed.

Objective and importance:Fusion following anterior cervical discectomy has been implicated in the acceleration of degenerative changes in the adjacent spinal segments. Discectomy followed by implantation of an artificial cervical disc maintains the functionality of the spinal unit, while still providing excellent symptomatic relief. We describe our preliminary experience with implantation of the Bryan Cervical Disc System in two cases of single-level cervical disc herniation.Clinical presentation:Two male patients presented with a left C6 radiculopathy, without evidence of myelopathy. Magnetic resonance imaging revealed a disc herniation at C5-6 in both cases. Pre-operative flexion and extension radiographs demonstrated preserved motion at the involved levels.Intervention/technique:Following a standard anterior cervical decompression, precision drilling of the vertebral endplates was carried out using a drill attached to a bed-mounted, gravitationally-referenced retraction frame. An artificial cervical disc, composed of a polyurethane nucleus with titanium endplates, was fitted between the contoured endplates without fixation to the vertebral bodies. No complications were experienced during the insertion of the prosthesis, or in the postoperative course. Both patients experienced immediate postoperative resolution of their radicular pain and were discharged from hospital the following day. At nine months following surgery, both patients continue to have complete relief of radicular symptoms. Postoperative radiographs at six months following surgery confirm accurate placement of the prosthesis and preserved mobility of the functional spinal unit.Conclusion:Insertion of the Bryan artificial cervical disc prosthesis following anterior cervical discectomy is a relatively straightforward procedure, which appears to be safe and provides good clinical results, without requiring additional surgical time. Long-term follow-up is required to assess its safety, efficacy, and ability to prevent adjacent segment degeneration.

OBJECTIVE: Anterior lumbar interbody fusion (ALIF) has gained popularity for the treatment of degenerative disease of the lumbar spine. In this report, we present our experience with the ALIF procedure for treatment of failed back surgery syndrome (FBSS) in a noncontrolled prospective cohort. METHODS: In a 2-year period, we treated patients diagnosed with FBSS with ALIF. Clinical and radiological outcomes were recorded in a prospective, nonrandomized, longitudinal manner. Neurological, pain, and functional outcomes were measured preoperatively and 12 months alter surgery. Operative data, perioperative complications, and radiological and clinical outcomes were recorded. RESULTS: Thirty-three patients with a preoperative diagnosis of FBSS, with degenerative disc disease (n = 17), postsurgical spondylolisthesis (n = 13), or pseudarthrosis (n = 3), underwent ALIF. Back pain, leg pain, and functional status improved significantly, by 76% (P < 0.01), 80% (P < 0.01), and 67% (P < 0.01), respectively. CONCLUSION: On the basis of our results, we found ALIF to be a safe and effective procedure for the treatment of FBSS for selected patients.

Object. It is recognized that cortical dysplasia (CD) is associated with an increased incidence of glioneuronal neoplasms. Among hypothetical considerations, there is the possibility that CD and other neuronal migration abnormalities harbor dysmature cells with the potential to give rise to glioneuronal neoplasms. Such cells, if present, would be reasonably expected to display immature features. The goal of the present study was to characterize the expression of nestin, a neuroepithelial precursor/stem cell antigen, in CD, along with other pathological and clinical features of this entity. Methods. Clinical and surgical features of 10 recent cases meeting the histological criteria for CD were reviewed. Expressions of nestin, MAP2, neurofilament, and glial fibrillary acidic protein (GFAP) were assessed using immunohistochemical analysis and confocal scanning laser microscopy. Immunoreactivity for both glial and neuronal antigens as well as nestin was found in a select group of cells within regions of CD. Immunohistochemical and confocal microscopic findings demonstrated that these cells with neuronal or ambiguous features are a mixed population, some of which are dysmature neurons (positive for nestin and MAP2), whereas others are astrocytic (positive for nestin and GFAP). Conclusions. Further insight into the nature of nestin-positive neurons may shed light on the cause and pathogenesis of the associated glioneuronal tumors and the accompanying chronic seizures.