Cervical spondylotic amyotrophy: a systematic review.

PURPOSE: Cervical spondylotic amyotrophy (CSA) is characterized by upper limb muscle weakness and atrophy, without sensory deficits. The pathophysiology of CSA has been attributed to selective injury to the ventral nerve root and/or anterior horn of the spinal cord. This review aimed to delineate the history of CSA and to describe the epidemiology, etiology, pathophysiology, classification, clinical features, radiological and electrophysiological assessment, diagnosis, differential diagnosis, natural history and treatment of CSA. METHODS: A comprehensive search of PubMed, EMBASE, Cochrane library and Web of Science databases was conducted, from their inception to April 3, 2018. RESULTS: Clinically, CSA is classified into three types: a proximal-type (involving the scapular muscles, deltoid and biceps), a distal-type (involving the triceps and muscles of the forearm and hand) and a diffuse-type (involving features of both the distal- and proximal-type). Diagnosis requires documentation of muscle atrophy, without significant sensory deficits, supported by careful neurological, radiological and neurophysiological assessments, with amyotrophic lateral sclerosis, Parsonage-Turner syndrome, rotator cuff tear and Hirayama disease being the principle differential diagnoses. Conservative management of CSA includes cervical traction, neck immobilization and physical therapy, with vitamin B12 or E administration being useful in some patients. Surgical treatment, including anterior decompression and fusion or laminoplasty, with or without foraminotomy, is indicated after conservative treatment failure. Factors associated with a poor outcome include the distal-type CSA, long symptom duration, older age and greater preoperative muscle weakness. CONCLUSION: Although the disease process of CSA is self-limited, treatment remains challenging, leaving scope for future studies. These slides can be retrieved under Electronic Supplementary Material.

A Convenient Non-harm Cervical Spondylosis Intelligent Identity method based on Machine Learning.

Cervical spondylosis (CS), a most common orthopedic diseases, is mainly identified by the doctor's judgment from the clinical symptoms and cervical change provided by expensive instruments in hospital. Owing to the development of the surface electromyography (sEMG) technique and artificial intelligence, we proposed a convenient non-harm CS intelligent identify method EasiCNCSII, including the sEMG data acquisition and the CS identification. Faced with the limit testable muscles, the data acquisition method are proposed to conveniently and effectively collect data based on the tendons theory and CS etiology. Faced with high-dimension and the weak availability of the data, the 3-tier model EasiAI is developed to intelligently identify CS. The common features and new features are extracted from raw sEMG data in first tier. The EasiRF is proposed in second tier to further reduce the data dimension, improving the performance. A classification model based on gradient boosted regression tree is developed in third tier to identify CS. Compared with 4 common machine learning classification models, the EasiCNCSII achieves best performance of 91.02% in mean accuracy, 97.14% in mean sensitivity, 81.43% in mean specificity, 0.95 in mean AUC.

Classification of Diffusion Tensor Metrics for the Diagnosis of a Myelopathic Cord Using Machine Learning.

In this study, we propose an automated framework that combines diffusion tensor imaging (DTI) metrics with machine learning algorithms to accurately classify control groups and groups with cervical spondylotic myelopathy (CSM) in the spinal cord. The comparison between selected voxel-based classification and mean value-based classification were performed. A support vector machine (SVM) classifier using a selected voxel-based dataset produced an accuracy of 95.73%, sensitivity of 93.41% and specificity of 98.64%. The efficacy of each index of diffusion for classification was also evaluated. Using the proposed approach, myelopathic areas in CSM are detected to provide an accurate reference to assist spine surgeons in surgical planning in complicated cases.

The Spinal Cord Line Can Predict Postoperative Recovery for Multilevel Cervical Spondylotic Myelopathy.

OBJECTIVE: To report a new index, the spinal cord (SC) line, and a new classification to predict postoperative recovery effect in patients with multilevel cervical spondylotic myelopathy (CSM). METHODS: On T2-weighted magnetic resonance imaging (MRI) of the cervical spine, point A is the posteroinferior point of the spinal cord at C2, and point B is the posterosuperior point of the spinal cord at C7. The SC line is defined as a line connecting A and B. The posterior surface of the compressor at the compression level does not exceed the line in SC line type I, touches the line in type II, and exceeds the line in type III. Between January 2010 and January 2015, 121 patients with multilevel CSM who underwent surgery through an anterior approach (anterior cervical corpectomy with fusion or anterior cervical discectomy and fusion) or a posterior approach (laminoplasty or laminectomy) in our hospital were studied retrospectively. The patients were classified into 3 groups according to SC line type (I, II, or III). RESULTS: In the anterior surgical approach group, the Japanese Orthopaedic Association (JOA) recovery rate at the last follow-up was 84.88 ± 3.06% for SC line type I, 78.05 ± 2.89% for type II, and 68.69 ± 3.21% for type III. In the posterior surgical approach group, the JOA recovery rate at last follow-up was 69.35 ± 8.73% for type I, 58.05 ± 5.88% for type II, and 47.98 ± 4.31% for type III. The anterior surgery approach was associated with a higher postoperative recovery rate than the posterior surgery approach in type II and type III groups (type II anterior vs. type II posterior: 78.05 ± 2.89% vs. 58.05 ± 5.88%, P = 0.003; type III anterior vs. type III posterior: 68.69 ± 3.21% vs. 47.98 ± 4.31%, P = 0.001). In contrast, the anterior and posterior surgery were associated with similar postoperative recovery rates in the type I group (84.88 ± 3.06% vs. 69.35 ± 8.73%; P = 0.820). CONCLUSIONS: The SC line and its classifications can predict postoperative recovery in patients with multilevel CSM.

The relationship between changes of cervical sagittal alignment after anterior cervical discectomy and fusion and spino-pelvic sagittal alignment under roussouly classification: a four-year follow-up study.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) is widely used in the treatment of cervical degenerative disease; however, the variation of cervical sagittal alignment changes after ACDF has been rarely explored. The purpose of this study is to determine the relationship between changes of cervical sagittal alignment after ACDF and spino-pelvic sagittal alignment under Roussouly classification. METHODS: A cohort of 133 Chinese cervical spondylotic patients who received ACDF from 2011 to 2012 was recruited. All patients were categorized with Roussouly Classification. Lateral X-ray images of global spine were obtained, and preoperative and postoperative parameters were measured and analyzed, including C2-C7 angles (C2-C7), C0-C7 angles (C0-C7), external auditory meatus (EAM) tilt, sacral slope (SS), thoracic kyphosis (TK), lumbar lordosis (LL), spinal sacral angles (SSA), Superior adjacent inter-vertebral angle (SAIV), inferior adjacent inter-vertebral angle (IAIV) and et al. The Wilcoxon signed-rank test was used for intragroup comparisons preoperatively and at postoperative 48 months. RESULTS: Among the parameters, C2-C7 and C0-C7 showed significant increase, while EAM TK, and IAIV decreased significantly. In type I, EAM and TK decreased significantly, however SS showed a significant increase; in type II, TK showed a significant decrease, but SSA showed a significant increase; in type III, a significant increase of C0-C7 was observed with a significant decrease in EAM, nevertheless, LL, SS and SSA showed significant decreases; and in type IV, C2-C7 showed a significant increase and EAM decreased significantly. The percentage of lordotic alignment in cervical spine increased, which was presenting in type I, III and IV. Nevertheless, the amount of patients with straight cervical alignment increased in type II. CONCLUSION: The backward movement of head occurs is the compensatory mechanism in cervical sagittal alignment modifications after ACDF. The compensatory alteration of spino-pelvic sagittal alignment varied in different Roussouly type.

Prediction of myelopathic level in cervical spondylotic myelopathy using diffusion tensor imaging.

PURPOSE: To investigate the use of a newly designed machine learning-based classifier in the automatic identification of myelopathic levels in cervical spondylotic myelopathy (CSM). MATERIALS AND METHODS: In all, 58 normal volunteers and 16 subjects with CSM were recruited for diffusion tensor imaging (DTI) acquisition. The eigenvalues were extracted as the selected features from DTI images. Three classifiers, naive Bayesian, support vector machine, and support tensor machine, and fractional anisotropy (FA) were employed to identify myelopathic levels. The results were compared with clinical level diagnosis results and accuracy, sensitivity, and specificity were calculated to evaluate the performance of the developed classifiers. RESULTS: The accuracy by support tensor machine was the highest (93.62%) among the three classifiers. The support tensor machine also showed excellent capacity to identify true positives (sensitivity: 84.62%) and true negatives (specificity: 97.06%). The accuracy by FA value was the lowest (76%) in all the methods. CONCLUSION: The classifiers-based method using eigenvalues had a better performance in identifying the levels of CSM than the diagnosis using FA values. The support tensor machine was the best among three classifiers.

Results of surgical treatment of cervical spondylotic myelopathy in patients aged 75 years or more: a comparative study of operative methods.

INTRODUCTION: The number of surgical procedures in elderly patients has been increasing as the population has grown older; recently, spine surgeons have been more likely to encounter elderly patients with cervical myelopathy in need of surgical treatment. There are many reports about surgical treatment of elderly patients with cervical spondylotic myelopathy (CSM); however, there are no studies about the proper selection of surgical methods and comparison of their results in CSM patients aged ≥ 75 years. The objective of this study was to review the results of operative methods in CSM patients aged ≥ 75 years. METHODS: Forty-three consecutive cases with an average age of 79 years that underwent surgical treatment were included in this study. The neurological severity was assessed using the Japanese Orthopaedic Association score for cervical myelopathy (JOA). The JOA scores were evaluated before surgery and at final follow-up. There were 21 laminoplasty procedures (from C3 to C7), 13 selective laminoplasty procedures (one above and one below the affected intervertebral level), and nine anterior decompression and fusion procedures. A selective laminoplasty was performed in cases with general complications and was diagnosed as one intervertebral level both clinically and electrophysiologically. Surgical results were compared among the three treatment groups. RESULTS: The average preoperative JOA score was 7.7 points and the average JOA recovery rate was 45 %. There were three cases of C5 palsy and one wound infection. Operative time and intraoperative bleeding in the selective laminoplasty group were significantly smaller than those in the other groups. There was no significant difference in the JOA recovery rates among the groups. CONCLUSIONS: Selective laminoplasty is less invasive and the surgical results in our study were almost good. It also has good short-term results. However, the indication for surgery has to be selected carefully in elderly CSM patients.

[Degenerative diseases of the spine]. / Degenerative Erkrankungen der Wirbelsäule.

Degenerative alterations of the spine are among the most common causes of complaints of the musculoskeletal system. Imaging procedures are an established component of diagnostics and differential diagnoses. A reduction in height of the intervertebral space and sclerotization of the basal and covering plates are part of the first radiological alterations and in the further course can be accompanied by formation of spondylophytes, arthrosis of the intervertebral joints and degenerative vertebral surface gliding. However, early changes of the mobile segments can often not be visualized in x-ray images. Computed tomography (CT) and magnetic resonance imaging (MRI) substantially improve the diagnostic options. Using MRI the spinal column and the surrounding soft tissues can be visualized in 3-D and a differential diagnostic differentiation between inflammatory, traumatized or neoplastic processes is possible. A lack of correlation between the imaging findings and clinical symptoms remains problematic. A meaningful interpretation of x-ray images and MRI can only be made with the appropriate knowledge of the symptoms and possible diseases.

MRI classification of interspinous ligament degeneration of the lumbar spine: intraobserver and interobserver reliability and the frequency of disagreement.

Posterior spinal ligament pathology is becoming increasingly recognized as a significant cause of low back pain. Despite the growing clinical importance of interspinous ligament degeneration in low back pain patients, formal reliability studies for the magnetic resonance imaging (MRI) evaluation of interspinous ligaments have not been performed. We proposed an MRI classification system for interspinous ligament degeneration and conducted a comprehensive reliability and reproducibility assessment. Fifty patients who had low back pain with or without leg discomfort (26 males and 24 females) with a mean age of 48.8 years (range 23-85 years) were studied. The classification for lumbar interspinous ligament degeneration was developed on the basis of the literature using mid-sagittal T1- and T2-weighted images. Three spine surgeons independently graded a total of 200 interspinous ligament levels. Intraobserver and interobserver reliability were assessed by kappa statistics. The frequency of disagreement was also identified. The intraobserver agreement was excellent in all readers (kappa range 0.840-0.901). The interobserver agreement was lower as expected, and was substantial to excellent (kappa range 0.726-0.818). Overall complete agreement was obtained in 87.8% of all interspinous ligament levels. A difference of 1, 2, and 3 grades occurred in 8.1, 3.0, and 1.1% of readings, respectively. This proposed MRI classification of interspinous ligament degeneration was simple, reliable, and reproducible. Its use as a standardized nomenclature in clinical and radiographic research may be recommended.