Of these, 9% are symptomatic, depending on the competence of the lower esophageal sphincter (LES). 95% of these are "sliding" hiatal hernias, in which the LES protrudes above the diaphragm along with the stomach, and only 5% are the "rolling" type (paraesophageal), in which the LES remains stationary, but the stomach protrudes above the diaphragm.Hiatal hernias are most common in North America and Western Europe and rare in rural African communities. Some have proposed that insufficient dietary fiber and the use of a high sitting position for defecation may increase the risk. References


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This could be the result of a degenerative process of the spine (such as osteoarthritis) or a developmental defect which is present at birth. In the most severe cases of spondylolisthesis cauda equina syndrome can result. Inflammatory conditions
Chronic spinal inflammatory conditions such as Paget disease, neurosarcoidosis, chronic inflammatory demyelinating polyneuropathy, ankylosing spondylitis, rheumatoid disease of the spine, and chronic tuberculosis can cause it. This is due to the spinal canal narrowing that these kinds of syndromes can produce. Risk factors
Individuals most at risk for disc herniation are the most likely to develop CES. Race has little influence with the notable exception that African Americans appear slightly less likely to develop CES than other groups. Middle age also appears to be a notable risk factor, as those populations are more likely to develop a herniated disc; heavy lifting can also be inferred as a risk factor for CES.Other risk factors include obesity and being female. Diagnosis
Diagnosis is first suspected clinically based on history and physical exam and usually confirmed by an MRI scan or CT scan, depending on availability. Bladder scanning and loss of catheter sensation can also be used to evaluate bladder dysfunction in suspected cases of cauda equina syndrome and can aid diagnosis before MRI scanning. Early surgery in acute onset of severe cases has been reported to be important. Prevention
Early diagnosis of cauda equina syndrome can allow for preventive treatment. Signs that allow early diagnosis include changes in bowel and bladder function and loss of feeling in groin.