Clinical Signs Of Myelopathy Research Articles

Risk predictive score and cord morphology classification for intraoperative neuromonitoring alerts in kyphosis surgery

BACKGROUNDIntraoperative neuromonitoring (IONM) alert is one of the worrying events of kyphosis corrective surgery, which can result in a postoperative neurological deficit. To our knowledge, there is no risk prediction score to predict such events in patients undergoing kyphosis surgery. PURPOSETo develop a new preoperative MRI-based cord morphology classification (CMC) and risk prediction score for predicting IONM alerts in patients with kyphotic deformity. STUDY DESIGNRetrospective analysis of prospectively collected data. PATIENT SAMPLEAbout 114 patients undergoing surgical correction for kyphotic deformity. OUTCOME MEASURESIntraoperative neuromonitoring alerts and postoperative neurological status using AIS grading. METHODSKyphotic deformity patients undergoing posterior spinal fusion were retrospectively reviewed. Based on the morphology of the spinal cord and surrounding CSF in MRI, there are 5 types of cord. Type 1 (normal cord): circular cord with surrounding visible CSF between the cord and the apex, Type 2 (flattened cord): cord with <50% distortion at the apex with obliteration of the anterior CSF; Type 3 (deformed cord): cord with >50% distortion at the apex with complete obliteration of the surrounding CSF; Type 4 (stretched cord): the cord is stretched and atrophied over the apex of the curve. Type 5 (translated cord): horizontal translation of the cord at the apex with buckling collapse of the vertebral column. Preoperative radiographs were used to measure the preoperative sagittal cobbs angle, sagittal deformity angular ratio (S-DAR), sagittal vertical axis (SVA), apex of the curve, and type of kyphosis. Clinical data like the duration of symptoms, clinical signs of myelopathy, neurological status (AIS grade), grade of myelopathy using the mJOA score, and type of osteotomy were documented. Multivariate logistic regression was used to determine the risk factors for IONM alerts and the risk prediction score was developed which was validated with new cohort of 30 patients. RESULTSA total of 114 patients met the inclusion criteria. IONM alerts were documented in 33 patients (28.9%), with full recovery of the signal in 25 patients and a postoperative deficit in 8 patients. Rate of IONM alerts was significantly higher in Type 5 (66%), followed by Type 4 (50%), Type 3 (21.1%), Type 2 (11.1%), and Type 1 (11.1%) (p-value<.001). Based on multiple logistic regression, 7 factors, namely preoperative neurological status, mJOA score≤6, presence of signs of myelopathy, apex of the curve above T5, preoperative sagittal cobbs, S-DAR, and MRI-based CMC, were identified as risk predictors. The value for the risk factors varies from 0 to 4, and the maximum total risk score was 13. The cut-off value of 6 had good sensitivity (84.9%) and specificity (77.8%) indicating a high risk for IONM alerts. The AUC of the predictive model was 0.92, indicating excellent discriminative ability. CONCLUSIONWe developed and validated a risk predictive score that identifies patients at risk of IONM alerts during kyphosis surgery. Identification of such high-risk patients (risk score≥6) helps in proper evaluation and preoperative counselling and helps in providing a proper evidence-based reference for treatment strategies.

Evidence-based commentary on the diagnosis, management, and further research of degenerative cervical spinal cord compression in the absence of clinical symptoms of myelopathy.

Degenerative cervical myelopathy (DCM) represents the final consequence of a series of degenerative changes in the cervical spine, resulting in cervical spinal canal stenosis and mechanical stress on the cervical spinal cord. This process leads to subsequent pathophysiological processes in the spinal cord tissues. The primary mechanism of injury is degenerative compression of the cervical spinal cord, detectable by magnetic resonance imaging (MRI), serving as a hallmark for diagnosing DCM. However, the relative resilience of the cervical spinal cord to mechanical compression leads to clinical-radiological discordance, i.e., some individuals may exhibit MRI findings of DCC without the clinical signs and symptoms of myelopathy. This degenerative compression of the cervical spinal cord without clinical signs of myelopathy, potentially serving as a precursor to the development of DCM, remains a somewhat controversial topic. In this review article, we elaborate on and provide commentary on the terminology, epidemiology, natural course, diagnosis, predictive value, risks, and practical management of this condition-all of which are subjects of ongoing debate.

Atypical Heterotopic Bone Formation Rear to the Functioning Cervical Artificial Disc Prosthesis Causing Cervical Spondylotic Myelopathy

Although heterotopic ossification (HO) might occur in a substantial proportion of cervical disc arthroplasty-switched spinal segments, it is predominantly discovered at the anterior vertebral edges of the treated interspace. Herein, we present the case of a 63-year-old woman who presented with clinical signs of myelopathy almost 5 years after the implantation of a Mobi-C disc prosthesis for C6-7 soft disc herniation. As shown by magnetic resonance imaging and computed tomography, spinal cord compression and a consequent signal change inside the cord were attributed to bony spurs from HO posterior to the still-moving prosthesis. Initial full posterior decompression through C6-7 bilateral laminectomy added to posterior stabilization almost fully relieved the patient’s functional and sensory changes from myelopathy. However, the device, as well as the ectopic bone deposits, had to be removed, and switching to anterior arthrodesis was necessary due to the imminent aggravation and progression of cervical kyphotic curvature from the still-functioning device. To the authors’ knowledge, such extensive bone accumulation posterior to a functional Mobi-C cervical prosthesis causing myelopathy has not yet been reported in the literature. Conversion to solid fusion would be preferred to posterior decompression for the sake of maintaining cervical curvature.

Clinical, MRI and histopathological findings in a dog with distemper meningomyelitis

A 14‐month‐old female entire German Shepherd dog presented with a five‐day history of acute onset, progressive, non‐ambulatory paraparesis, with lateralisation to the right. The neurolocalisation was to the L4‐S1 spinal cord segments. MRI of the thoracic, lumbar and sacral spinal cord revealed multifocal, ill‐defined, T2‐weighted hyperintense, intramedullary lesions, which were moderately contrast‐enhancing, becoming more defined and ovoid to nodular after injection of gadolinium‐containing contrast medium. The lesions affected both white and grey matter and were lateralised mainly to the right side. PCR tests on blood and cerebrospinal fluid were positive for canine distemper virus (CDV). Despite intensive treatment, the dog developed myoclonus and severe fever and was humanely euthanased. Postmortem examination confirmed the presence of spinal cord lesions consistent with CDV. Distemper rarely presents with clinical signs of myelopathy exclusively and there is a scarcity of description of MRI findings of distemper meningomyelitis in the literature.

RESULTS OF TREATMENT OF CERVICAL DISCOPATHY WITH PEEK INTERBODY CAGES AT THREE LEVELS WITHOUT PLATE FIXATION

ABSTRACT Objective: To present the results of treatment of patients with cervical discopathy by anterior cervical approach, discectomy and placement of a PEEK interbody cage without anterior plate fixation. Methods: Retrospective, cross-sectional study from March 2013 to March 2015. Sixteen patients with radiculopathy or clinical signs of myelopathy were included; all patients underwent cervical surgery through anterior approach, discectomy, and placement of PEEK cages on three levels. Decompression levels were determined according to the correlation between preoperative radiological and clinical findings. Results: Sixteen patients predominantly male were included, with mean age of 50 years at the onset of the condition. Ten patients had involvement of C4-C5, C5-C6, C6-C7 levels, and six patients C3-C4, C4-C5 and C5-C6. Fourteen patients had cervicobrachialgia and two myelopathy. The preoperative visual analog scale average was 8/10 and the average postoperative value at 6 months was 3/10. At 6 months, there was no radiological evidence of recurrence. One patient had non-fatal complications. Conclusions: The treatment of cervical discopathy by anterior approach with interbody fusion with PEEK cage on three levels, with no plate fixation seemed to be safe and effective with better long-term results in terms of pain and myelopathy. The clinical results compare favorably with other similar series and, most importantly, the complications associated with anterior fixation plate are avoided.

The Relationship between Preoperative Clinical Presentation and Quantitative MRI Features in Patients with Degenerative Cervical Myelopathy

Introduction Degenerative Cervical Myelopathy (DCM) encompasses a group of degenerative conditions of the cervical spine, including cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL), that result in spinal cord pathology through static and dynamic injury mechanisms. While there are a constellation of degenerative findings that present in patients with DCM on MRI, large studies have shown that cervical cord compression and signal changes on MRI can present in asymptomatic or population based cohorts as well. It is therefore the objective of the present research to investigate the correlations between clinical and MRI findings and address this area of controversy. Material and Methods One hundred and fourteen patients enrolled in the prospective and multicenter AOSpine CSM North American study with complete MRI and clinical data were evaluated. Patients were enrolled if they had ≥1 clinical signs of myelopathy. Mid-sagittal MRIs were assessed for maximum spinal cord compression (MSCC) and maximum cord compromise (MCC). Additionally, the presence of T1 and T2 signal changes assessed, and the degree of T2 signal hyperintensity deviation was evaluated by computing a signal change ratio (SCR). MRI features were then statistically related with the presence of upper and lower limb neurological symptoms as well as generalized neurological dysfunction using t-tests. The relationship between duration of symptoms and quantitative MRI features was assessed using Spearman's rank correlation coefficient. Results The average T2 signal change ratio at the region of interest was 1.31, and the mean MCC and MSCC were ~49% and 34%, respectively. Numb hands ( p = 0.01) and Hoffmann's sign ( p = 0.003) were associated with greater MSCC; broad-based, unstable gait ( p = 0.042), impairment of gait ( p = 0.008) and Hoffmann's sign ( p = 0.013) were associated with greater MCC; Numb hands ( p = 0.037), Hoffmann's sign ( p = 0.017), Babinski sign ( p = 0.002), lower limb spasticity ( p = 0.011), L'Hermitte's phenomena ( p = 0.045), hyperreflexia ( p = 0.004), and presence of T1 hypointensity were associated with a greater deviation of signal intensity on T2 MRI. Patients with the presence of T2 signal hyperintensity also had greater MSCC ( p &lt; 0.001) and MCC ( p &lt; 0.001). Patients with L'Hermitte's phenomenon had a statistically significant lower SCR ( p = 0.045), indicating that they more commonly presented with diffuse and faint, or absence of T2 signal hyperintensities. Conclusion MSCC and MCC were predominately associated with upper limb and lower limb manifestations, respectively. SCR was associated with upper limb, lower limb and general neurological deficits. Hoffmann's sign was the only clinical parameter which occurred more commonly in patients with a greater MSCC, MCC and SCR, supporting its role as a sensitive diagnostic tool. L'Hermitte's phenomenon presented more commonly in patients with a lower SCR and thus may serve to indicate mild pathology and potential for reversibility. Going forward, it would be interesting to investigate these correlations over multiple preoperative time periods to evaluate the validity and evolution of these relationships. Ultimately, the culmination of such research may serve as a prelude to the construction of an evidence based prediction model that may help to differentiate between patients that remain stable and identify those who are likely to deteriorate without surgical intervention.

Heterotopic ossification associated with myelopathy following cervical disc prosthesis implantation

This case report presents a 37-year-old man with clinical signs of myelopathy almost 9years after implantation of a Bryan disc prosthesis (Medtronic Sofamor Danek, Memphis, TN, USA) for C5/C6 soft disc herniation. As demonstrated on MRI and CT scan, spinal cord compression was caused by bony spurs due to heterotopic ossification posterior to the still moving prosthesis. The device, as well as the ectopic bone deposits, had to be removed because of myelopathy and its imminent aggravation. Conversion to anterior spondylodesis was performed.

Role of magnetic resonance imaging in predicting surgical outcome in patients with cervical spondylotic myelopathy.

Ambispective, retrospective cohort study from prospectively collected data. Cervical spondylotic myelopathy is the commonest cause of spinal cord impairment in the elderly population worldwide. Although magnetic resonance imaging (MRI) is the primary imaging modality for confirming the diagnosis, its role in predicting surgical outcome remains unclear. Two hundred seventy-eight patients with 1 or more clinical signs of myelopathy were enrolled; and they underwent decompression surgery. Complete baseline clinical and MRI data were available for 102 patients. MRI parameters measured included presence/absence of signal change on T1 and T2, T2 signal quantitative factors, and anatomical measurements. A dichotomized postoperative modified Japanese Orthopedic Association (mJOA) score at 6 months was used to characterize patients with mild myelopathy (≥16) and those with substantial residual neurological impairment (<16). Univariate analysis assessed the relationship between baseline parameters and outcome. Multivariate logistic regression was conducted after a conceptual division of variables into 3 groups: T1 signal analysis, T2 signal analysis, and anatomical measurements. Baseline mJOA (P<0.001; odds ratio [OR]=1.644, 95% confidence interval [95% CI]: 1.326-2.037), maximum canal compromise (MCC) (P=0.0322; OR=0.965, 95% CI: 0.934-0.997), T2 hyperintensity region of interest area (P=0.0422; OR=0.67; 95% CI: 0.456-0.986), and sagittal extent (P=0.026; OR=0.673; 95% CI: 0.475-0.954) were significantly associated with outcome univariately. The final model was comprised of T1 hypointensity (P=0.029; OR=0.242; CI: 0.068-0.866), MCC (P=0.005; OR=0.940; CI: 0.90-0.982) and baseline mJOA (P<0.001; OR=1.743; CI: 1.353-2.245), yielding an area under the receiver operating characteristic curve (AUC) of 0.845. Baseline mJOA is a strong predictor of postsurgical outcome in cervical spondylotic myelopathy at 6 months. However, a model inclusive of MCC and T1 hypointensity assessment provides superior predictive capacity. This suggests that MRI analysis has a significant role in predicting surgical outcome. 3.

IMAGING DIAGNOSIS—SPINAL CORD HISTIOCYTIC SARCOMA IN A DOG

A 12-year-old mixed breed dog was presented for evaluation of progressive paraparesis and ataxia. Magnetic resonance (MR) imaging was performed and identified multifocal intradural spinal cord mass lesions. The lesions were hyperintense in T2-weighted sequences, isointense to mildly hyperintense in T1-weighted sequences with strong contrast enhancement of the intradural lesions and spinal cord meninges. Spinal cord neoplasia was suspected. A diagnosis of intramedullary spinal cord histiocytic sarcoma, confined to the central nervous system, was confirmed histopathologically. Spinal cord histiocytic sarcoma is a rare neoplasm, but should be included in the differential diagnosis for dogs with clinical signs of myelopathy.

Spinal Cord Sarcoidosis

Sarcoidosis is a granulomatous disorder of unknown cause that affects the spinal cord in fewer than 1% of patients who suffer from it. We conducted a retrospective case-control study of 31 patients with spinal cord sarcoidosis and compared them to 30 patients with myelopathies of other causes to analyze their clinical, laboratory, and magnetic resonance imaging (MRI) profiles and to assess their long-term prognoses. Thirty-one patients presented with clinical signs of myelopathy and were diagnosed with sarcoidosis. Twenty-two of these patients had biopsy-proven noncaseating granulomas. In 9 patients, sarcoidosis involved only a neurologic localization. Patients in the control group were mainly diagnosed with multiple sclerosis or optic neuromyelitis. Patients with sarcoidosis were more likely to have elevated levels of C-reactive protein (CRP), elevated lactate dehydrogenase (LDH), and hypergammaglobulinemia in serum, as well as a higher protein content and white blood cell count in cerebrospinal fluid. Spinal cord MRIs performed in 26 patients with spinal cord sarcoidosis revealed T2-hyperintensities that were extensive and heterogeneous with a central distribution in axial slides. Twenty-six patients with spinal cord sarcoidosis presented neurologic sequelae after follow-up (mean, 64 +/- 8 mo), although 2 patients completely recovered. Neurologic sequelae correlated with cerebrospinal fluid white blood cell counts. One-third of the patients had a monophasic course of the disease, another third had a relapsing-remitting course, and the remaining third had a progressive course. Four patients had pulmonary embolism during follow-up. Spinal cord sarcoidosis remains a diagnostic dilemma since neurologic localization is frequently the only manifestation. Because treatment for spinal cord sarcoidosis is far different from treatment for other myelopathies, such as multiple sclerosis and optic neuromyelitis, diagnosis of sarcoidosis remains an important challenge. Here, we show that spinal cord MRI and blood and cerebrospinal markers may be useful tools in the diagnosis of spinal cord sarcoidosis. We suggest that accessory salivary gland biopsies, chest X-rays, protein electrophoresis, and blood levels of CRP and LDH should be obtained for each patient with subacute myelopathy. We also recommend paying careful attention to thromboembolism in patients with spinal cord sarcoidosis because of systemic disease and their decreased mobility.

Spinal glomus-type arteriovenous malformations: microsurgical treatment in 20 cases

Glomus-type spinal arteriovenous malformations (AVMs) are rare. In the literature only small series and anecdotal reports can be found, and there are no prospective series elucidating the natural course or the superiority of 1 treatment regimen over another (such as surgery versus embolization versus conservative treatment). Microsurgical treatment of spinal AVMs often seems difficult because many lesions are not anatomically suitable for primary microsurgical occlusion and are therefore treated with first-line neuroradiological interventions or not at all. Between 1989 and 2005, 20 patients with glomus-type AVMs underwent microsurgical treatment at 2 major neurosurgical centers in Germany. The history of symptoms in these patients ranged from 2 days to 11 years. Four patients presented with subarachnoid hemorrhage, 2 with intramedullary hematoma, 4 with paresthesia or pain, and 10 with clinical signs of myelopathy. Seven patients underwent partial embolization prior to microsurgery. The authors only operated on AVMs accessible from a dorsal or dorsolateral approach. Neurological status was assessed with the McCormick classification scheme. Follow-up data were obtained from outpatient records. Three patients were interviewed over the telephone and 4 patients were not available for follow-up evaluation. Surgery was performed via a laminectomy in 14 and hemilaminectomy in 6 patients. The microsurgical technique used consisted of retrograde dissection of the AVM from the venous side in most cases. Four (20%) of 20 patients showed worsening of neurological symptoms to a worse McCormick grade, probably caused by suspected venous stasis directly after surgery, however only 1 patient (5%) suffered permanent deterioration after surgery. In 14 patients postoperative angiography proved complete occlusion in 11 patients, including the presence of a remnant requiring a second operation with complete occlusion thereafter in 1 patient. In 3 patients occlusion was incomplete: a small residual AVM remained in 1 patient, and a discrete feeding vessel without a vein was evident in 2 patients. Spinal cord AVMs are rare. If embolization is not possible, surgery may be indicated in selected cases. Spinal AVMs behave differently after incomplete occlusion either surgically or with embolization. A postoperative reduction in symptoms is frequent despite the presence of small remnants, and the risk of neurological deficits seems relatively low even in residual AVMs. Therefore, treatment need not necessarily aim at complete occlusion if that would be associated with an unacceptably high risk of neurological deficits.

Myelography, CT, and MRI of the spinal canal in patients with myelopathy: a prospective study.

A prospective study including myelography, CT, and MRI was performed on 36 patients with clinical signs of myelopathy. Evoked potentials and spinal fluid examinations were also carried out. Based on our findings, the patients could be classified as suffering from cryptogenic myelopathy (n = 12), multiple sclerosis (n = 6), spinal stenosis (n = 6), or miscellaneous myelopathies (n = 12). The diameter of the spinal cord was normal in the 2 first groups of patients and of same magnitude evaluated by myelography and CT, while MRI constantly gave higher figures. In only four of the patients important new information was added by CT and MRI (syringomyelia, myelitis, lipomatosis) compared with myelography, although a more precise visualization was often provided. Further diagnostic progress in patients with myelopathy of undetermined etiology may be obtained by including supplementary MRI of the brain disclosing multiple sclerosis in several cases.

Meningomyelitis in dogs: a retrospective review of 28 cases (1999 to 2007)

To characterise dogs with meningomyelitis and to compare signalment, body temperature and vaccination status to a representative control group. Dogs with meningomyelitis were identified retrospectively. Signalment, history, vaccination status, body temperature, severity of neurological dysfunction (modified Frankel score), diagnostic procedures, aetiology, survival to discharge and long-term survival were analysed. Affected dogs were younger (P<0.05) and more frequently hound or toy breeds (P<0.05) when compared with controls. Hound and toy breed dogs less than or equal to three years of age had a 13 times higher odds of meningomyelitis compared with other breeds (P<0.001). General proprioceptive ataxia, limb paresis and paraspinal hyperaesthesia were the most common clinical signs. Meningomyelitis of unknown aetiology and granulomatous meningomyelitis were the most common diagnoses. The median time to death or continued follow-up in dogs alive at discharge was 213 days. Meningomyelitis resulted in death or euthanasia in 14 of 28 dogs. Clinical signs improved or resolved in seven of 28 dogs. Meningomyelitis is a differential diagnosis for dogs with clinical signs of myelopathy. Young dogs and toy or hound breeds seem to be predisposed. Clinical signs of meningomyelitis improve or resolve in some dogs.

Observer Agreement of Spine Stenosis on Magnetic Resonance Imaging Analysis of Patients With Cervical Spine Myelopathy

Objectives The purpose of this study was to measure the intraobserver and interobserver reliability of magnetic resonance detection of cervical spondylotic myelopathy with and without operational guidelines. Methods Seven radiologists examined images from 10 patients with cord signal abnormalities and clinical signs of myelopathy. Radiologist examined films twice, with and without operational guidelines designed to define stenotic changes, while blinded to the clinical findings of the patients. Analyses included a Fleiss κ assessment of intraobserver and interobserver reliability. Results Results demonstrated high percentage of agreement and strong intraobserver reliability and variable Fleiss κ values for interobserver assessment. Operational guidelines did not improve the intraobserver or interobserver agreement. Conclusion Although the percentage of agreement was high in some cases, the κ agreement was low—most likely a result of the base rate problem of a κ analysis. Sample bias toward severe degenerative changes resulted in highly prevalent selections and κ adjusted values. Nonetheless, the results do suggest that substantial intraobserver κ agreement and a wide range of interobserver κ agreement exists among trained radiologists during detection of stenotic changes associated with cervical spondylotic myelopathy.

Integrated Outcome Assessment After Anterior Cervical Discectomy and Fusion

The authors conducted a cross-sectional study. Integrated assessment of adjacent instability (AI), myelocompression (MC), magnetic resonance imaging (MRI) signs of myelopathy (MRISM), physician-assessed clinical signs and symptoms, including clinical signs of myelopathy (CSM), patients' self-reported symptoms and quality of life after anterior cervical discectomy and fusion (ACDF). Fifty-four patients who had ACDF between 1986 and 1995 received MRI scans, conventional and flexion/extension radiographs to assess myelocompression, MRISM, fusion, and AI. Clinical outcome was assessed using signs and symptoms based on selected items of Odom's criteria, Oswestry low back pain disability questionnaire, and the neck disability index. Patients reported their quality of life (QL) on a standardized instrument (Profiles of QL of Chronically Ill [PLC]) and by a specific validated Cervical Spine Symptom Scale (CSSS). Myelocompression was found more frequently than expected (24%). MRISM were seen in 2 patients (4%). One of the 2 patients developed CSM. Fusion was achieved in 94% (with kyphosis in 17%). AI was found in 30%. However, only myelocompression but not AI was associated with statistically significant decreases in most QL scores (i.e., everyday capabilities, positive mood) and high cervical spine symptom burden (all P's < 0.05). The study results underline the need for a better understanding of the biomechanical changes in the adjacent unfused segments. Consensus is needed on postoperative follow-up guidelines, including pain management strategies. Future studies on the outcome of ACDF will profit from an integrated outcome approach, including assessments based on imaging, physicians, and patients.

The value of somatosensory and motor evoked evoked potentials in pre-clinical spondylotic cervical cord compression.

Previous studies have yielded conflicting data concerning the value of evoked potential parameters in the assessment of clinical relevance of cervical cord compression in clinically "silent" cases. The aim of this study was to assess the value of somatosensory (SEP) and motor evoked potentials (MEP) in the evaluation and prediction of the clinical course, by means of a 2-year follow-up prospective electrophysiological and clinical study performed in patients with clinically "silent" spondylotic cervical cord compression. Thirty patients with MR signs of spondylotic cervical cord compression but without clinical signs of myelopathy were evaluated clinically and using SEPs and MEPs during a 2-year period. The results of the study showed that SEPs and MEPs documented subclinical involvement of cervical cord in 50% of patients with clinically "silent" spondylotic cervical cord compression. During the 2-year period clinical signs of cervical myelopathy were observed in one-third of patients with entry EP abnormality in comparison with no patients with normal EP tests. Combined SEPs and MEPs proved to be a valuable tool in the assessment of the functional relevance of subclinical spondylotic cervical cord compression. Normal EP findings predict a favourable 2-year clinical outcome.