Objective: To measure pelvic canal diameter in dogs from a ventrodorsal radiographic view of the pelvic region, to define a normal pelvic canal diameter, to evaluate risk factors associated with stenosis of the pelvic canal secondary to sacroiliac separation, and to determine clinical signs associated with pelvic canal stenosis.
Design: Retrospective case series.
Animals: 84 case-group and 46 control-group dogs.
Procedure: Medical records and radiographs of dogs with conditions unrelated to pelvic fracture (control group) and dogs with sacroiliac separation (case group) in which radiographs were obtained before surgery, after surgery, or after fracture healing were reviewed. Discriminant analysis was used to determine a normal pelvic canal diameter. An ANOVA and Dunnett's two-sided test were used to determine factors associated with pelvic canal stenosis.
Results: Pelvic canal diameter ratio determined from control-group dogs was > or = 1.1. Pelvic canal diameter ratios were significantly less for case-group dogs on radiographs obtained before surgery and after fracture healing than for control-group dogs, regardless of fracture type or treatment, except for dogs with ilial fractures treated conservatively. Pelvic canal diameter ratios did not differ for case-group dogs on radiographs obtained after surgery from those for control-group dogs, except when ilial fractures were surgically reduced. None of the dogs had clinical signs associated with pelvic canal stenosis.
Clinical implications: Pelvic canal diameter in dogs can be determined from a ventrodorsal radiographic view of the pelvic region. Dogs with pelvic fractures that have a normal pelvic canal diameter before surgery tend to have a normal pelvic canal diameter after fracture healing.