title: Lumbar spine MRI in upright position for diagnosing acute and chronic low back pain: statistical analysis of morphological changes.
abstract: BACKGROUND
  Patients with low back pain frequently demonstrate recumbent magnetic resonance imaging (MRI) alterations not always related to homogeneous clinical symptoms. The purpose of this study was to evaluate and quantify the statistical significance of variations of some anatomical parameters of the lumbosacral spine and reveal occult disc pathologies from recumbent to upright position in patients with acute and chronic low back pain.
  
  
  METHODS
  Fifty-seven patients complaining of low back pain (27 women, 30 men) underwent dynamic lumbosacral MRI with a 0.25-T tilting system (G-scan Esaote). We settled five parameters for which variations have been evaluated: lumbosacral angle, lordosis angle, L3-L4 intersomatic disc height, L3-L4 interspinous processes distance, and widest anteroposterior dural sac diameter. Images were obtained in both recumbent and upright positions.
  
  
  RESULTS
  Statistically significant differences [one-way analysis of variance (ANOVA), p = 0.0043] were found between each pair of values of parameters sampled in recumbent and upright positions. In 70 % of patients, on visual qualitative analysis only, an increment of disc protrusions and/or spondylolisthesis was found in the upright position; in three cases, in the upright position only, an interarticular pseudocyst was found.
  
  
  CONCLUSIONS
  Dynamic MRI with an open-configuration, low-field tilting MRI system is a feasible and promising tool to study degenerative pathology of the spine. Moreover, in cases of low back pain with negative MRI in the recumbent position or in patients with pain in the upright position only, tilting MRI permits visualization of occult spine and disc pathologies in patients with acute or chronic low back pain.
authors.affiliation: Department of Orthopedics and Traumatology, Tor Vergata University of Rome, Policlinico Tor Vergata Foundation, V.le Oxford 81, 00133, Rome, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: Tarantino
authors.forename: Ezio
authors.initials: E
authors.lastname: Fanucci
authors.forename: Riccardo
authors.initials: R
authors.lastname: Iundusi
authors.forename: Monica
authors.initials: M
authors.lastname: Celi
authors.forename: Simone
authors.initials: S
authors.lastname: Altobelli
authors.forename: Elena
authors.initials: E
authors.lastname: Gasbarra
authors.forename: Giovanni
authors.initials: G
authors.lastname: Simonetti
authors.forename: Guglielmo
authors.initials: G
authors.lastname: Manenti
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D059350:Chronic Pain / Q000175:diagnosis; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D017116:Low Back Pain / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged