Devoted to diagnostic and interventional spine imaging and therapeutics


Seated MRI Increases Insight Into Degenerative Disc Disease: A Study of 320 Patients 2005

General Spine

Francis W. Smith, MD


For the past twenty five years we have studied the lumbar spine, by MRI, in the supine position. This position is often the most comfortable for the patient, when in fact their symptoms are often worse when either standing or sitting. With the availability of an

Methods & Materials

320 patients (163 males and 157 females) aged between 24 and 78 years (mean 57 years), suffering from low back pain and sciatica, were scanned using a 0.6T


Of 960 discs examined 522 were considered to be normal. These "Normal discs" showed no significant change in disc height between supine and sitting.
2 - 4mm reduction in height anteriorly on forward flexion.
2 - 4mm reduction in height posteriorly on extension.
438 showed degenerative change in their nuclei, half of which behaved like normal discs and are considered to be normal and classified as degenerative change. The other half were classified as "Degenerate discs" showing 1 - 3mm change in disc height between supine and sitting. Reduction of greater than 3mm in disc height on flexion and extension and varying degrees of disc prolapse.
108 prolapsed discs showed reduction of posterior prolapse on forward flexion & increase in extension. Interestingly 23 showed the reverse.


We conclude that imaging of the spine in the erect standing and seated positions adds significantly to the diagnostic ability of MRI. The ability to study changes in the appearances and behaviour of those discs with reduced signal from their nuclei, will aid in the further understanding of degenerative disc disease.