Spine
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The case report presented herein shows tortuosity of the vertebral artery in a patient with cervical myelopathy. This case led the authors to evaluate 22 other patients who also had undergone anterior cervical fusion. They were studied before operation by either magnetic resonance imaging angiography or selective vertebral angiography. ⋯ This study suggests that vertebral artery loop formation is developed associated with cervical spondylotic changes. During the anterior decompression of cervical spondylotic myelopathy or radiculopathy, the looped vertebral artery could be injured by an excessive wide rejection of the bone or disc material. In the case of vertebral artery migration, the looped vertebral artery can even be injured by routine procedures.
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Lumbosacral nerve roots and dorsal root ganglia in relation to surrounding bony structures in normal subjects were investigated using magnetic resonance imaging. ⋯ The anatomy of the lumbar nerve roots and dorsal root ganglia and their relations to bony structures have been better defined in this study. Because of its more medial location, S1 radiculopathy may involve both the nerve root and dorsal root ganglion as a result of either disc herniation or degenerative L5-S1 facet changes. The relatively larger dorsal root ganglia and the greater dorsal root ganglion/foramen height ratios in the lower lumbar region may explain the higher incidence of L5 or S1 radiculopathy, particularly given the propensity to disc degeneration and intervertebral foraminal narrowing in the lower lumbar region.
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Experimental axial pullout tests of a new type of pedicle screw were done on cadaveric lumbar vertebrae. The manner in which specimens were secured in the testing apparatus was varied to determined influence of specimen fixation method on the maximum pedicle screw pullout force. ⋯ Polymer resin intrusion can have a significant effect on the biomechanical characteristics of the bone-pedicle screw interface. When polymer resins are used to secure vertebral specimens for in vitro biomechanical tests of the bone-pedicle screw interface, it is important to either prevent intrusion (e.g., with a latex wrapping) or document post-test (e.g., through the methods described in this article) that intrusion did not occur for the specimens included in the analysis.
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This is a brief review of the life and contributions to neurologic science of Sir William Gowers. He was a neurologist in England in the late 19th century who, before the availability of modern diagnostic aids, established the importance of clinical examination, including history and physical signs, in the diagnosis of neurologic disorders. ⋯ He arranged for his colleague, Sir Victor Horsley, to remove it and the operation was completely successful. He invented the patella hammer and his book "Manual of Diseases of the Nervous System" (in two volumes) was the standard reference until early in the 20th century.
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This case report illustrates two patients with paraplegia of late onset resulting from cord compression in the hyperlordotic thoracic or thoracolumbar spine proximal to a healed tuberculous kyphosis. ⋯ Compensatory hyperlordosis of the thoracic or thoracolumbar spine commonly occurs in patients with severe tuberculous thoracolumbar or lumbosacral kyphosis. Degenerative spinal stenosis and cord compression at such hyperlordotic segment can cause late onset paraplegia. The blood supply of these chronically compressed cords is precarious and the risk of surgery is high.