title: Foraminal changes with distraction and compression of the L4/5 and L5/S1 segments.
abstract: The width of the foramen in the lumbar spine is directly related to the position of the vertebrae. In an MRI study the measurements of the cross-sectional area of the neuroforamen of L4/5 and L5/S1 in neutral position, segmental distraction and compression were calculated. Nine cadaver specimens were investigated and the foraminal width of L4/5 and L5/S1 was measured. In both segments of all specimens the foraminal space significantly enlarged under distraction and decreased under compression. In the L4/5 segment the average relative difference between distraction and compression was 27%.
authors.affiliation: Spine Unit, Schulthess Hospital, Zürich, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Humke
authors.forename: D
authors.initials: D
authors.lastname: Grob
authors.forename: W
authors.initials: W
authors.lastname: Grauer
authors.forename: A
authors.initials: A
authors.lastname: Sandler
authors.forename: J
authors.initials: J
authors.lastname: Dvorak
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000293:injuries / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012447:Sacrum / Q000293:injuries / Q000473:pathology*; D016103:Spinal Fractures / Q000175:diagnosis*