Canine intervertebral disc fenestration using a vacuum-assisted tissue resection device.

OBJECTIVE:
Describe the use and feasibility of a novel vacuum-assisted tissue resection device (VRD) for canine intervertebral disc fenestration, and compare the effectiveness of manual fenestration to the VRD.
STUDY DESIGN:
Randomized prospective study.
ANIMALS:
Canine cadavers (n = 15).
METHODS:
A cadaveric lumbar spine study was performed to compare the use of manual fenestration to a novel VRD for intervertebral disc fenestration. Both fenestration groups were compared to a control group. Effectiveness of fenestration was assessed by calculating a ratio of remaining nuclear weight postfenestration to total nuclear volume. Fenestrated discs with lower ratios were indicative of greater removal of nucleus pulposus.
RESULTS:
There was a statistically significant reduction in mean ratio (±SD) of remaining nuclear weight to volume with both fenestration groups compared to controls (0.39 ± 0.07; P < .001). There was an improved ratio using the VRD (0.23 ± 0.09) compared to manual fenestration (0.30 ± 0.10); this was not statistically significant (P = .069). It was technically difficult to fenestrate the disc spaces at L5-L6 and L6-L7 because of location and anatomy, resulting in a statistically significant increase in the median ratio of nuclear weight-to-volume ratios in both manual and VRD fenestration groups when compared to the more cranial L4-L5 disc spaces, 0.32 ± 0.08, and 0.35 ± 0.08 versus 0.25 ± 0.13 at L4-L5 (P = .026 and P = .004, respectively).
CONCLUSIONS:
The VRD is a feasible instrument for canine intervertebral disc fenestration. It is at least as effective as manual fenestration, and provides additional safety features.