Measurement of lumbar spine flexion-extension using a low-field open-magnet magnetic resonance scanner.
OBJECTIVE
The authors investigated the feasibility of using a low-field open-magnet magnetic resonance (MR) scanner to acquire functional flexion-extension images for range of motion (ROM) measurements on the lumbar spine.


METHODS
Seventeen healthy subjects with no symptoms of back pain (age range, 22-59 years) were scanned in a low-field open-magnet MR scanner in the flexed, neutral, and extended positions. Each image was downloaded to a computer workstation for subsequent flexion-extension, lordosis, and ROM measurement.


RESULTS
Data from two subjects were not analyzed because their images did not show all the lumbar vertebrae. For the remaining 15, there was a large variation in the magnitude of the ROM values (range, 9 degrees-70 degrees; mean 36.4 degrees, SD 16.5 degrees). However, there was a significant correlation between age and ROM (r = -0.63; P < 0.05).


CONCLUSIONS
The low-field open-magnet MR scanner provides a method for noninvasive imaging of the lumbar spine, allowing the subject freedom of movement in the horizontal plane. This enables functional flexion-extension images of the lumbar spine to be acquired.
Harvey
S B
SB
Department of Bio-Medical Physics, University of Aberdeen, Foresterhill, United Kingdom.
Smith
F W
FW
Hukins
D W
DW
D000328:Adult; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008159:Lumbar Vertebrae / Q000033:anatomy & histology / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008875:Middle Aged; D009068:Movement; D012016:Reference Values