Wasting of the small hand muscles in upper and mid-cervical cord lesions.
Four patients are described with destructive rheumatoid arthritis of the cervical spine and neurogenic wasting of forearm and hand muscles. The pathological connection is not immediately obvious, but a relationship between these two observations is described here with clinical, radiological, electrophysiological and necropsy findings. Compression of the anterior spinal artery at upper and mid-cervical levels is demonstrated to be the likely cause of changes lower in the spinal cord. These are shown to be due to the resulting ischaemia of the anterior part of the lower cervical spinal cord, with degeneration of the neurones innervating the forearm and hand muscles. These findings favour external compression of the anterior spinal artery leading to ischaemia in a watershed area as the likeliest explanation for this otherwise inappropriate and bizarre phenomenon. (+info)
A clinical study of motor evoked potentials using a triple stimulation technique.
Amplitudes of motor evoked potentials (MEPs) are usually much smaller than those of motor responses to maximal peripheral nerve stimulation, and show marked variation between normal subjects and from one stimulus to another. Consequently, amplitude measurements have low sensitivity to detect central motor conduction failures due to the broad range of normal values. Since these characteristics are mostly due to varying desynchronization of the descending action potentials, causing different degrees of phase cancellation, we applied the recently developed triple stimulation technique (TST) to study corticospinal conduction to 489 abductor digiti minimi muscles of 271 unselected patients referred for possible corticospinal dysfunction. The TST allows resynchronization of the MEP, and thereby a quantification of the proportion of motor units activated by the transcranial stimulus. TST results were compared with those of conventional MEPs. In 212 of 489 sides, abnormal TST responses suggested conduction failure of various degrees. By contrast, conventional MEPs detected conduction failures in only 77 of 489 sides. The TST was therefore 2.75 times more sensitive than conventional MEPs in disclosing corticospinal conduction failures. When the results of the TST and conventional MEPs were combined, 225 sides were abnormal: 145 sides showed central conduction failure, 13 sides central conduction slowing and 67 sides both conduction failure and slowing. It is concluded that the TST is a valuable addition to the study of MEPs, since it improves detection and gives quantitative information on central conduction failure, an abnormality which appears to be much more frequent than conduction slowing. This new technique will be useful in following the natural course and the benefit of treatments in disorders affecting central motor conduction. (+info)
Cauda equina syndrome in ankylosing spondylitis: a report of six cases.
Six patients with ankylosing spondylitis and features of a cauda equina syndrome are described. The myelographic findings are discussed in relation to the pathogenesis of the disorder and its natural history. Present experience suggests that the cauda equina syndrome is a more common complication of ankylosing spondylitis than is usually thought. (+info)
A clinico-pathological study of cervical myelopathy in rheumatoid arthritis: post-mortem analysis of two cases.
Two patients who developed cervical myelopathy secondary to rheumatoid arthritis were analyzed post mortem. One patient had anterior atlanto-axial subluxation (AAS) combined with subaxial subluxation (SS), and the other had vertical subluxation (VS) combined with SS. In the patient with AAS, the posterior aspect of the spinal cord demonstrated severe constriction at the C2 segment, which arose from dynamic osseous compression by the C1 posterior arch. A histological cross-section of the spinal cord at the segment was characterized by distinct necrosis in the posterior white columns and the gray matter. In the patient with VS, the upper cervical cord and medulla oblongata showed angulation over the invaginated odontoid process, whereas no significant pathological changes were observed. At the level of SS, the spinal cord was pinched and compressed between the upper corner of the vertebral body and the lower edge of the lamina. Histologically, demyelination and gliosis were observed in the posterior and lateral white columns. (+info)
MR of CNS sarcoidosis: correlation of imaging features to clinical symptoms and response to treatment.
BACKGROUND AND PURPOSE: Sarcoidosis is an idiopathic systemic granulomatous disease, recognized in a patient when clinical and radiologic findings are confirmed by histopathologic analysis. The objective was to identify a relationship between MR imaging and clinical findings in CNS sarcoidosis. METHODS: The clinical charts of 461 patients with biopsy-proved sarcoidosis were reviewed retrospectively. Criteria for including patients in the study included those with symptoms referable to the CNS, excluding those with another explanation for their symptoms, those with headaches or other subjective complaints without accompanying objective findings, and those with peripheral neuropathy other than cranial nerve involvement or myopathy without CNS manifestations. Thirty-four of 38 patients whose conditions met the criteria for CNS sarcoidosis underwent a total of 82 MR examinations. The positive imaging findings were divided into categories as follows: pachymeningeal, leptomeningeal, nonenhancing brain parenchymal, enhancing brain parenchymal, cranial nerve, and spinal cord and nerve root involvement. Treatment response, clinical symptomatology, and any available histopathologic studies were analyzed with respect to imaging manifestations in each of the categories. RESULTS: Eighty-two percent of the patients with sarcoidosis with neurologic symptoms referable to the CNS had findings revealed by MR imaging. However, eight (40%) of 20 cranial nerve deficits seen at clinical examination of 13 patients were not seen at contrast-enhanced MR imaging, and 50% of the patients with symptoms referable to the pituitary axis had no abnormal findings on routine contrast-enhanced MR images. In contradistinction, 44% of 18 cranial nerves in nine patients with MR evidence of involvement had no symptoms referable to the involved cranial nerve. Clinical and radiologic deterioration occurred more commonly with leptomeningeal and enhancing brain parenchymal lesions. CONCLUSION: MR imaging can be used to confirm clinical suspicion and to show subclinical disease and the response of pathologic lesions to treatment. (+info)
Idiopathic spinal cord herniation: value of MR phase-contrast imaging.
We report two patients with an idiopathic transdural spinal cord herniation at the thoracic level. Phase-contrast MR imaging was helpful in showing an absence of CSF flow ventral to the herniated cord and a normal CSF flow pattern dorsal to the cord, which excluded a compressive posterior arachnoid cyst. (+info)
Myelopathy due to calcification of the cervical ligamenta flava: a report of two cases in West Indian patients.
Two cases of cervical myelopathy due to calcification of the ligamenta flava (CLF) are described for the first time in black patients from the French West Indies. A pre-operative CT scan differentiated the diagnosis from one of ossification of the ligamenta flava. Microanalysis on the operatively excised specimen in one patient revealed a mixture of calcium pyrophosphate dihydrate crystals and hydroxypatite crystals. Poor outcome in one patient contrasting with excellent recovery in the other one, who had undergone posterior decompressive laminectomy, emphasizes the importance of surgery in the management of CLF. (+info)
Spinal xanthomatosis: a variant of cerebrotendinous xanthomatosis.
We describe seven Dutch patients from six families with a slowly progressive, mainly spinal cord syndrome that remained for many years the sole expression of cerebrotendinous xanthomatosis (CTX). MRI demonstrated white matter abnormalities in the lateral and dorsal columns of the spinal cord. Post-mortem examination of one of the patients showed extensive myelin loss in these columns. An array of genotypes was found in these patients. We conclude that 'spinal xanthomatosis' is a clinical and radiological separate entity of CTX that should be included in the differential diagnosis of 'chronic myelopathy'. (+info)