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when you bent you feel some vibration
(i.e. some times of abnormal sensation) in your lower lumbar portion. when bending your spinal cord
is also bending. so if there would have been any sort of prolapse of disc or sprue over the lumbar vertebral
region you may get such type of abnormal feeling around your back portion. so if possible do the CT Scan
of whole spine and Xray too.
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