Double Pelvic Osteotomy (DPO) in Canine Hip Dysplasia - Clinical and Radiographic Evaluation

Abstract

Background: Hip dysplasia (HD) in dogs is a common orthopaedic issue affecting both young and adult animals, leading to degenerative joint disease (DJD) and decreased quality of life. Various diagnostic methods, including radiography, are employed to assess the severity of the condition. Treatment options range from surgical interventions, such as juvenile pubic symphysiodesis (JPS) and pelvic osteotomies, to salvage procedures like total hip arthroplasty. This study focuses on the peri- and postoperative evaluation of double pelvic osteotomy (DPO) as a treatment option for dogs aged 4-6 months diagnosed with hip dysplasia. Materials, Methods & Results: In this study, 12 dogs aged 4-6 months were examined at the Surgery Department of Selcuk University's Faculty of Veterinary Medicine, either due to hind limb lameness complaints or for routine hip dysplasia examinations. Following clinical and radiological assessments, all dogs were diagnosed with hip dysplasia, and subsequently, a double pelvic osteotomy (DPO) was performed as the chosen treatment. Clinical examinations involved recording stair climbing, walking, and running gait patterns, along with conducting the Ortalani, Barlow, and Barden tests. Radiological assessments were conducted for ventro-dorsal radiographs, administered under medetomidine sedation. To accurately predict passive laxity in the coxofemoral joint, the distraction stress radiography technique was employed. This method utilized a neutral stance compression radiograph, an acrylic bar placed between proximal femurs, and assessment of subluxation based on the adduction force produced. The distraction index, calculated by measuring displacement between mid-acetabular and mid-femoral head, helped evaluate hip joint abnormalities. For the DPO procedure, sedation was administered using medetomidine, followed by the induction of anesthesia with either ketamine or propofol. In intubated cases, isoflurane was administered, and vital signs were continuously monitored. The surgical steps included osteotomy of the os pubis and corpus ossis ilii. The dog was positioned dorsolaterally for the pubic osteotomy, with careful preservation of vital structures. Subsequent osteotomy in the lateral recumbent position involved an incision from the iliac crest to the greater trochanter, with iliac vessels isolated and ligated. Protection of soft tissues during osteotomy was ensured using Hohmann retractors, and a 20% curvilinear osteotomy was performed on the exposed ossis ala ilium. Post-osteotomy, the caudal ilium was held laterally, and an osteotomy plate was fixed to the caudal line of the ilium. A caudally fixed osteotomy plate (left or right, 3.5, 250, 6 holes - 1 cortical, 5 locking) was then fixed to the cranial ilium by osteotomy reduction. This comprehensive approach, encompassing diagnosis, treatment, and surgical technique details, underscores the study's dedication to addressing hip dysplasia in young dogs, providing valuable insights for veterinary orthopaedics and patient care. Discussion: The study suggests that DPO is a viable alternative to traditional methods, with lower complication rates and positive clinical outcomes. The postoperative period showed promising improvements in various parameters, indicating the potential efficacy of DPO in treating hip dysplasia in growing dogs. Long-term follow-up and additional studies, including CT scan results, are recommended for a more comprehensive understanding of the surgical outcomes and to establish DPO as a safe and effective technique. Keywords: bilateral pelvic osteotomy, distraction index, femoral inclination angle, hip dysplasia, norberg angle.