ABSTRACT
Objective To explore a method for establishment of tethered cord syndrome model with neural axial stretch in pig. Methods Eighteen adult pigs were randomized into three groups. Sham group: L1-5 spinal cords were exposed; control group: Li-r, bilateral pedicle screws were placed after exposure of L1-5 spinal cords; and experiment group: L1-5 spinal cords were exposed, then bilateral pedicle screws were placed, and finally L1-5 intervertebral spaces were extended axially, with six in each group. At different time points, the pigs in the three groups were subjected to X ray. hindlimb behaviors, urodynamics, somatosensory evoked potential, laser speckle imaging for blood flow and histopathology examination, and the examination results were compared and analyzed. Results In the sham group and control group, there was no obvious change in L1-5 intervertebral space height, hindlimb motor nerve function scores, urodynamics, somatosensory evoked potentials or laser speckle imaging for blood flow before and after operation; and the spinal cord and nerve structure were normal or nearly normal in the histopathology. In the experiment group, compared with before distraction, Liintervertebral height after distraction was significantly increased, hindlimb motor nerve function score was significantly decreased, latency of P-wave of sematosensory evoked potential was significantly extended and the amplitude was significantly decreased, and blood flow 011 the surface of spinal cord was significantly reduced (P