title: Torsional injury resulting in disc degeneration: I. An in vivo rabbit model.
abstract: Torsional injuries may be a precursor to intervertebral disc degeneration, but published rabbit models indicate a latent time of 6 months. We describe a rabbit model in which instability and disc degeneration appear within 3 months. Sixty-five male New Zealand rabbits underwent presurgical irradiation to inhibit heterotopic bone formation. Control animals then underwent either a soft-tissue release or facetectomy and capsulotomy, whereas experimental animals received surgery and an acute 30 degrees torsional lumbar injury. Capsulotomy, as well as facetectomy without torsion, failed to effect disc degeneration. However, the rabbits that received torsion exhibited clear indications of degenerative disc changes (thinning, increased PLA2 levels, and decreased nucleus pulposus volume) within 60-90 days. The observations associate disc degeneration with a destabilizing acute torsional injury.
authors.affiliation: Department of Orthopaedics and Rehabilitation, The University of Texas Medical Branch, Galveston 77555-0792, USA.
authors.forename: A G
authors.initials: AG
authors.lastname: Hadjipavlou
authors.forename: J W
authors.initials: JW
authors.lastname: Simmons
authors.forename: J P
authors.initials: JP
authors.lastname: Yang
authors.forename: L X
authors.initials: LX
authors.lastname: Bi
authors.forename: G A
authors.initials: GA
authors.lastname: Ansari
authors.forename: B S
authors.initials: BS
authors.lastname: Kaphalia
authors.forename: D J
authors.initials: DJ
authors.lastname: Simmons
authors.forename: C L
authors.initials: CL
authors.lastname: Nicodemus
authors.forename: J T
authors.initials: JT
authors.lastname: Necessary
authors.forename: R
authors.initials: R
authors.lastname: Lane
authors.forename: O
authors.initials: O
authors.lastname: Esch
mesh_terms: D000818:Animals; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D008297:Male; D010741:Phospholipases A / Q000378:metabolism; D054467:Phospholipases A2; D011817:Rabbits; D011859:Radiography; D013122:Spinal Diseases / Q000175:diagnosis / Q000209:etiology* / Q000378:metabolism; D013124:Spinal Injuries / Q000150:complications* / Q000209:etiology; D014102:Torsion Abnormality
chemical_list: D010741:Phospholipases A; D054467:Phospholipases A2