Lumbar spinal stenoses may induce symptoms following an individually typical latency on standing or when walking due to swelling of the cauda equina, which leads to compression. This is referred to as neurogenic claudication. The symptoms of lumbar spinal stenosis can be explained by an increase in lumbar lordosis and spinal canal stenosis in an upright position compared to the sitting position or if spondylolisthesis is present by a shift of the vertebrae while standing and walking. Following an individually characteristic distance, walking becomes associated with deep muscular pain and with neurological deficits, such as sensory deficits and paresis in the lower limbs, which resolve within minutes when the affected person sits or lies down. Activities performed in a flexed posture, such as cycling often cause less problems than walking. For the same reason, walking uphill may be tolerated better than walking downhill. Clinical neurological examination at rest may be entirely normal but there is usually pain on hyperextension of the lumbar spine. [from
HPO]