title: Canine hip dysplasia treated by juvenile pubic symphysiodesis. Part I: two year results of computed tomography and distraction index.
abstract: OBJECTIVE
  To measure one and two year effects of juvenile pubic symphysiodesis (JPS) in puppies defined as 'at-risk' for canine hip dysplasia (CHD) using the following objective hip conformation criteria: Acetabular angle (AA), dorsal acetabular rim angle (DARA) and hip laxity (PennHIP© distraction index (DI).
  
  
  METHODS
  Controlled clinical case study.
  
  
  METHODS
  Thirty-nine dysplastic puppies (six controls).
  
  
  METHODS
  The dogs were anaesthetised and acetabular angle, DARA, and DI values were obtained by computed tomography and radiography preoperatively. Electro-cautery fusion of the pubic symphysis was performed between 12 - 24 weeks of age. The imaging was repeated at one and two years of age.
  
  
  RESULTS
  Significant hip improvements were seen at the two-year follow-up appointments for: AA (JPS dogs 31% increase, control 3%), DARA (JPS 38% decrease, control 15%) and DI (JPS 41% decrease in laxity, controls 20%) for all postoperative versus preoperative values. Pubic fusion occurred with minor morbidity.
  
  
  CONCLUSIONS
  Juvenile pubic symphysiodesis resulted in significant improvements in hip conformation (AA and DARA), especially in mild to moderately lax hips (DI = 0.40-0.69). Most dogs with DI≥0.70 increased in osteoarthritis grade by two years of age.
  
  
  CONCLUSIONS
  Juvenile pubic symphysiodesis surgery at 12-24 weeks of age significantly improved hip conformation and decreased laxity in at-risk CHD dogs. Early-age (12 to 16 week) recognition of hip laxity offered greater JPS benefits than surgery performed at 19- to 24-weeks-old. Dogs with severe laxity (DI≥0.70) continued to increase in osteoarthritis. An early (12-16 weeks) positive laxity test (Ortolani) should alert one to obtain objective laxity determinations (PennHIP© DI).
authors.affiliation: Department of Surgical Sciences, University of Wisconsin, Madison, Wisconsin, USA. duelandt@svm.vetmed.wisc.edu
authors.forename: R T
authors.initials: RT
authors.lastname: Dueland
authors.forename: W M
authors.initials: WM
authors.lastname: Adams
authors.forename: A J
authors.initials: AJ
authors.lastname: Patricelli
authors.forename: K A
authors.initials: KA
authors.lastname: Linn
authors.forename: P M
authors.initials: PM
authors.lastname: Crump
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging; D017668:Age of Onset; D000818:Animals; D001835:Body Weight; D004285:Dogs; D005500:Follow-Up Studies; D006619:Hip Dysplasia, Canine / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000601:surgery*; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000601:surgery / Q000662:veterinary; D018579:Patient Selection; D010384:Pelvic Bones / Q000000981:diagnostic imaging / Q000601:surgery; D010808:Physical Examination; D011182:Postoperative Care / Q000662:veterinary; D011630:Pubic Bone / Q000000981:diagnostic imaging / Q000601:surgery; D011631:Pubic Symphysis / Q000000981:diagnostic imaging / Q000601:surgery*; D016059:Range of Motion, Articular; D014057:Tomography, X-Ray Computed / Q000662:veterinary; D016896:Treatment Outcome