Morphometrical analysis of the thoracolumbar dural sac in sheep using computed assisted myelography

M. Mageed; J.-C. Ionita; E. Ludewig; W. Brehm; K. Gerlach

doi:10.3415/VCOT-13-09-0116

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2014; 27(02): 124-129
DOI: 10.3415/VCOT-13-09-0116

Original Research

Schattauer GmbH

Morphometrical analysis of the thoracolumbar dural sac in sheep using computed assisted myelography

M. Mageed

¹Large Animal Clinic for Surgery, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany

²Department of Surgery and Anaesthesia, Faculty of Veterinary Medicine, University of Khartoum, Shambat, Khartoum, Sudan

,

J.-C. Ionita

¹Large Animal Clinic for Surgery, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany

,

E. Ludewig

³Department of Small Animal Medicine, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany

,

W. Brehm

¹Large Animal Clinic for Surgery, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany

,

K. Gerlach

¹Large Animal Clinic for Surgery, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany

› Author Affiliations

Abstract

Summary

Objectives

Sheep are frequently used as animal models in experimental spinal injury studies. Therefore, extensive knowledge of ovine spinal dimensions is essential for experimental design and interpretation of results obtained in these trials. This study aimed to obtain quantitative morphometrical data of the thoracolumbar dural sac in sheep and determine the anatomical relationship between the dural sac and the vertebral canal.

Methods

Computed assisted myelography imaging was carried out in five adult German Black-Headed Mutton sheep under general anaesthesia. Transverse images were acquired with 2 mm slice thickness from the first thoracic to the sixth lumbar vertebrae. Sagittal and transverse diameters and the cross-sectional area of the dural sac and vertebral canal were measured. To determine the anatomical relationship between the dural sac and vertebral canal, the pedicledural sac distance (PPSD) and the epidural space as well as the SAC (available space for the dural sac) were calculated.

Results

Sagittal diameters of the dural sac ranged from 5.1 to 12.0 mm. Transverse diameters ranged from 5.6 to 12.2 mm. The dural sac area covered 45.9% and 49.0% of the thoracic and lumbar vertebral canal area. The PDSD in the lumbar vertebrae was up to 15.8% larger than in the thoracic ones. The dural sac area was significantly positively correlated with the transverse diameter and area of the vertebral canal.

Clinical significance

The lumbar vertebral canal contained more space for the dural sac, which seems to be safer for testing spinal implants.

Keywords

Animal model - ovine - dural sac - myelography - computed tomography

Full Text

References

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