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Backache and the Lumbar Spinal Canal

This paper records measurement of the lumbar spinal canal by diagnostic ultrasound in more than 700 subjects from early infancy until the age of 65 years. It demonstrates the range of canal size in a South Yorkshire population. The canal is relatively wide in children, reaches a maximum diameter in the late teens, and reduces slightly by late adult life. This does not appear to be related to occupation. Comparisons are made with more than 700 patients with symptoms of back pain, especially patients with disabling disc symptoms, root entrapment syndrome, and neurogenic claudication. The size of the central canal is particularly significant in patients who have neurogenic claudication and disc symptoms. It is less significant in root entrapment syndrome.