Summary
Triple pelvic osteotomies (IPO) were evaluated in 40 clinical cases. In 39 cases,
these were young dogs with hip dysplasia; in one case, the TPO was used as a correction
for a hip luxation. Unilateral TPOs were performed in twenty patients, twelve with
traditional TPO (without additional ventral plate) and eight with additional ventral
plate fixation. Bilateral TPOs were performed in twenty patients, thirteen with traditional
TPO and seven with additional ventral plate. In traditional TPOs, evidence of implant
failure occurred in 5 of 12 unilateral and 11 of 13 bilateral procedures. In TPOs
with additional ventral plate fixation, minor screw loosening was detected in one
of eight unilateral and zero of seven bilateral procedures. Statistically TPOs without
additional ventral plate fixation had 9.2 times greater odds of screw loosening with
significantly greater acetabular segment displacement (p < 0.01). Two traditional
TPOs performed required additional surgery due to screw loosening. Other attempted
additional stabilization techniques used with the TPO procedure included ilial body
wiring, ischial body wiring, sacral screw purchase, and medial screw nuts, however
these methods did not prevent loosening and migration. TPO with additional ventral
plate fixation was highly effective at combating implant failure.
Keywords
Hip dysplasia - triple pelvic osteotomy - implant loosening
