Summary
Objectives: Retrospective comparison of dorsolateral (DLA) and ventrolateral (VLA) surgical approaches
for treatment of canine sacroiliac luxation using three different radiographic analyses.
Methods: Surgical cases with immediate and ≥ 4 week postoperative radiographs were reviewed
(Jan. 2000 to Jan. 2015). Exactness of reduction, screw position, and sacral body
screw purchase were assessed with three separate methods: single plane assessment
and orthogonal assessment with or without rotational limits.
Results: The reduction index (RI) for DLA and VLA was not significantly different with single
plane assessment (p = 0.0789), but it was significantly greater for DLA than VLA with
orthogonal assessment, with or without rotational limits (p = 0.0039, p = 0.0146).
No differences were observed with screw placement into the intended location (single
plane, and orthogonal assessment with or without rotational limits; p = 0.2941, p
= 0.4151, p = 0.3550, respectively). No differences were observed between mean screw
purchase index (SPI) and the 60% goal for the DLA (p = 0.1303, p = 0.9594, p = 0.7120)
or 50% goal for the VLA (p = 0.2224, p = 0.1401, p = 0.2224; single plane, and orthogonal
assessment with or without rotational limits). Implant loosening was present in four
DLA cases and one VLA case. No differences were observed in the number of cases or
number of screws that loosened (p = 0.3483 and p = 0.6873, respectively).
Clinical significance: The key factor demonstrated in maintaining screw and fixation stability was correct
screw placement within the sacral body, regardless of the surgical approach.
Keywords
Sacroiliac luxation - dorsolateral approach - ventrolateral approach - implant failure