Computed tomographic evaluation of dynamic alteration of the canine lumbosacral intervertebral neurovascular foramina

OBJECTIVE To develop a computed tomographic (CT) method to measure the volume of the lumbosacral intervertebral neurovascular foramina (IVF) in dogs, and determine the effect of the range of motion of the lumbosacral (LS) junction on this measurement in German shepherd dogs (GSDs) with degenerative lumbosacral stenosis (DLSS) compared to unaffected controls. STUDY DESIGN In vivo analysis and retrospective case series. SAMPLE POPULATION Twenty-four working Police GSDs, 12 diagnosed with DLSS and 12 unaffected by DLSS were compared to 10 Greyhounds without DLSS. METHODS Three-dimensional renderings of CT data were used to measure the lumbosacral foraminal volume of dogs positioned in dorsal recumbency with the LS junction alternately positioned in extension, neutral position, and flexion. RESULTS Volumetric analysis of the IVF was found repeatable for the extended and neutral positions (interclass correlation coefficient of 0.89 and 0.8, respectively). The mean lumbosacral IVF volume was decreased by 74% between LS flexion and extension in Greyhounds, compared to 79 and 85% reductions in GSDs unaffected and affected by DLSS, respectively. The lumbosacral IVF volume was decreased by 23% when comparing extended to neutral LS positions in Greyhounds, 29% in unaffected GSDs, and 31% in affected GSDs. IVF volumes were smaller in affected GSDs compared to unaffected GSDs (P < .05) and Greyhounds (P < .01). CONCLUSIONS Positioning the LS junction in full extension decreases the volume of the lumbosacral IVF. This dynamic narrowing was more pronounced in GSDs with signs of DLSS than in GSDs not overtly affected by DLSS.

[1]  N. Jeffery,et al.  What progress has been made in the understanding and treatment of degenerative lumbosacral stenosis in dogs during the past 30 years? , 2014, Veterinary journal.

[2]  R. Tucker,et al.  Lumbosacral foraminal ratios and areas using MRI in medium-sized dogs , 2014, Veterinary and Comparative Orthopaedics and Traumatology.

[3]  P. Mente,et al.  In vitro biomechanical comparison of the flexion/extension mobility of the canine lumbosacral junction before and after dorsal laminectomy and partial discectomy. , 2013, Veterinary journal.

[4]  L. Moore,et al.  Effects of body position, imaging plane, and observer on computed tomographic measurements of the lumbosacral intervertebral foraminal area in dogs. , 2011, American journal of veterinary research.

[5]  B. Meij,et al.  Degenerative lumbosacral stenosis in dogs. , 2010, The Veterinary clinics of North America. Small animal practice.

[6]  A. Worth,et al.  Degenerative lumbosacral stenosis in working dogs: Current concepts and review , 2009, New Zealand veterinary journal.

[7]  S. Werre,et al.  Effects of body position and clinical signs on L7-S1 intervertebral foraminal area and lumbosacral angle in dogs with lumbosacral disease as measured via computed tomography. , 2008, American journal of veterinary research.

[8]  F. Steffen,et al.  Surgical treatment of lumbosacral foraminal stenosis using a lateral approach in twenty dogs with degenerative lumbosacral stenosis. , 2007, Veterinary surgery : VS.

[9]  N. Suwankong,et al.  Agreement between computed tomography, magnetic resonance imaging, and surgical findings in dogs with degenerative lumbosacral stenosis. , 2006, Journal of the American Veterinary Medical Association.

[10]  S. Ferguson,et al.  Effects of anatomic conformation on three-dimensional motion of the caudal lumbar and lumbosacral portions of the vertebral column of dogs. , 2006, American journal of veterinary research.

[11]  Stephen J Ferguson,et al.  Three-dimensional motion pattern of the caudal lumbar and lumbosacral portions of the vertebral column of dogs. , 2004, American journal of veterinary research.

[12]  P. Shires,et al.  Endoscopic-assisted lumbosacral foraminotomy in the dog. , 2004, Veterinary surgery : VS.

[13]  I. Yang,et al.  A study of motor and sensory evoked potentials in chronic cauda equina compression of the dog , 2004, European Spine Journal.

[14]  J. Hudson,et al.  Computed tomography of the normal lumbosacral intervertebral disc in 22 dogs. , 2003, Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association.

[15]  C. Vite,et al.  Association of cauda equina compression on magnetic resonance images and clinical signs in dogs with degenerative lumbosacral stenosis. , 2002, Journal of the American Animal Hospital Association.

[16]  C. Banfield,et al.  Association between postoperative outcome and results of magnetic resonance imaging and computed tomography in working dogs with degenerative lumbosacral stenosis. , 2000, Journal of the American Veterinary Medical Association.

[17]  K. Inzana,et al.  Subclinical CT abnormalities in the lumbosacral spine of older large-breed dogs. , 2000, Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association.

[18]  L. De Risio,et al.  Degenerative lumbosacral stenosis. , 2000, The Veterinary clinics of North America. Small animal practice.

[19]  J. Mattoon,et al.  QUANTITATIVE SURVEY RADIOGRAPHIC EVALUATION OF THE LUMBOSACRAL SPINE OF NORMAL DOGS AND DOGS WITH DEGENERATIVE LUMBOSACRAL STENOSIS , 1993 .

[20]  R. Aspden,et al.  Measurement of Vertebral Foraminal Dimensions Using Three-Dimensional Computerized Tomography , 1993, Spine.

[21]  R. Delamarter,et al.  Experimental lumbar spinal stenosis. Analysis of the cortical evoked potentials, microvasculature, and histopathology. , 1990, The Journal of bone and joint surgery. American volume.

[22]  C. K. Lee,et al.  Lateral Lumbar Spinal Canal Stenosis: Classification, Pathologic Anatomy and Surgical Decompression , 1988, Spine.

[23]  B. Slocum,et al.  L7-S1 fixation-fusion for treatment of cauda equina compression in the dog. , 1986, Journal of the American Veterinary Medical Association.