A novel dynamic model for experimental spinal cord compression

Abstract

<jats:p content-type="fine-print"><jats:italic>Object.</jats:italic> The goal of this study was to develop a novel dynamic model for experimental spinal cord compression that closely approximates neoplastic epidural compression of the spinal cord in humans.</jats:p> <jats:p content-type="fine-print"><jats:italic>Methods.</jats:italic> In 30 New Zealand white rabbits, the thoracic spine was exposed via a posterior approach. On each side of one vertebral lamina a small hole was drilled caudal to the articular process. A silicone band was passed through these holes, forming a loop. The spinal dura mater was exposed via an interlaminar approach. The loop was brought into contact with the dura mater and fixed in its position encircling 270° of the circumference of the spinal cord. Thereafter, the loop was gradually tightened at set times by pulling at the ends of the band and fixing them again in their new position. The spinal cord was thus increasingly compressed in a circular and dynamic manner.</jats:p> <jats:p content-type="fine-print">Neurological deficits of various degrees were created in all animals in the compression group, and the compressive effect of the loop was reliably demonstrated on MR imaging. After decompression of the spinal cord, the neurological deficits were reversible in the majority of animals, and MR imaging revealed either no signal changes or only circumscribed ones within the cord. In contrast, MR images obtained in animals that did not recover revealed the occurrence of extensive chronic myelopathy.</jats:p> <jats:p content-type="fine-print"><jats:italic>Conclusions.</jats:italic> This novel model features reproducibility of paresis and neurological recovery. It is a dynamic model simulating circular tumor growth and is characterized by its easy, straightforward, and cost-saving applicability.</jats:p>

Is the speed of chronic compression an important factor for chronic spinal cord injury rat model?

“…Because it is difficult to examine these pathological mechanisms clinically, reliable animal models of chronic compression spinal cord injury are indispensable. Although a number of animal models of CSM have been developed, including the use of a balloon catheter [11], screw drilling [4], and dynamic compression [13], these models have a number of deficits including acute or subacute spinal cord injury during the modeling process, which can lead to marked pathological differences compared with the natural history of CSM. Furthermore, some models require repeated operation [4][5][6]11], while the pressure applied to the spinal cord does not have a linear effect on pathophysiological findings.…”

Ex vivo 1H MR spectroscopy and histology after experimental chronic spinal cord compression

“…Lastly the animal model of chronic spinal cord compression may represent a rather subacute compression than a chronic one and confers all the limitations that come along with every animal model of human disease (biomechanics, etc.). This has been discussed extensively previously in the context of the first description of the model (11,25).…”

“…For this study a model recently developed by our group for subacute and chronic spinal cord compression was used. The surgical steps are described in detail elsewhere (11). Briefly, after induction of anesthesia animals were positioned prone for exposure of the upper thoracic spine.…”

“…Postoperatively the animals underwent a neurological examination twice a day. The neurological grading was carried out according to Marquardt et al (11): grade V, no motor deficits (rabbits able to run); grade IV, mild weakness (rabbits able to walk but not to run); grade III, moderate weakness (rabbits able to stand but not to walk); grade II, marked weakness (movements of the limbs visible but rabbits not able to stand); grade I, severe weakness (only slight movements of the limbs visible); and Grade 0, paraplegia.…”