The use of interventional open MRI to assess the kinematics of the lumbar spine in patients with spondylolisthesis.
METHODS
Open interventional MRI techniques were used to investigate the intervertebral mobility of the lumbar spine in subjects with isthmic and degenerative spondylolisthesis. The findings were compared with those in a published database of subjects with no history of low back pain.


OBJECTIVE
To investigate patterns of intervertebral mobility in subjects with spondylolisthesis to determine the level of spinal instability in this population.


BACKGROUND
Subjects with spondylolisthesis have been considered to present with a special form of spinal instability. Consequently, this condition is frequently managed by spinal fusion. However, confusion exists regarding whether there is excessive motion at the level of the defect.


METHODS
For this study, 29 subjects presenting to spinal clinics with spondylolisthesis (15 isthmic and 14 degenerative) were recruited and compared with an existing database of control subjects. The motion characteristics of these subjects in flexed and extended positions were investigated using interventional open MRI of known precision. In all the subjects, the level of resting pain, the grade of slip, and the level of the defect were noted.


RESULTS
No mobility differences, in terms of both angular and translational motion, were found between the subjects with spondylolisthesis and those with no history of low back pain, suggesting that subjects with spondylolisthesis do not present with either instability or hypermobility.


CONCLUSIONS
A spondylolytic defect does not lead to detectable instability or hypermobility in the lumbar spine.
Department of Musculoskeletal Surgery, Imperial College School of Medicine, Charing Cross Hospital, London. a.mcgregor@ic.ac.uk
Alison H
AH
McGregor
Lisa
L
Anderton
Wady M W
WM
Gedroyc
Jonathon
J
Johnson
Sean P F
SP
Hughes
D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D013168:Spondylolisthesis / Q000473:pathology / Q000503:physiopathology*; D016683:Supine Position / Q000502:physiology