Perineal hernia: Retrospective study (long term FU and risk factors for recurrence and complications)

Objective
To evaluate the outcome of dogs with perineal hernia treated with transposition of the internal obturator muscle.

Design
Retrospective case series.

Animals
34 dogs.

Procedures
Medical records of dogs with perineal hernia surgically treated from 1998 to 2012 were reviewed. Diagnostic methods and surgical technique were recorded. Dogs were assigned preoperative and postoperative clinical sign scores. Complication and recurrence rates were evaluated over time. Risk factors were determined.

Results
Median follow-up time was 345 days (22 to 1,423 days). Complications were observed in 10 dogs. Tenesmus (10), dyschezia (8), fecal impaction (4), rectal prolapse (2), stranguria (4), hematochezia (2), urinary incontinence (2), diarrhea (1), urinary tract infection (1), and megacolon (1) occurred following surgery. Bladder retroflexion at the time of initial evaluation or surgery was not a risk factor for complication (hazard ratio, 1.72). One year after surgery, 51.2% dogs were free of complications. Three dogs developed a perineal hernia on the contralateral side between 35 and 95 days after surgery. The 1-year recurrence rate was 27.4%. Median time for recurrence was 28 days after surgery (range, 2 to 364 days). Postoperative tenesmus was a risk factor for the development of recurrence (hazard ratio, 2.27).

Conclusions and Clinical Relevance
Internal obturator muscle transposition was used for primary repair of perineal hernia in dogs. Recurrence has been recorded 1 year after surgery. Tenesmus was a risk factor for the development of recurrence after treatment of perineal hernia with internal obturator muscle transposition.