Comparative Studies of the Effects of Celecoxib and Acetaminophen in Fracture Healing in Dogs

Abstract

Fifteen dogs of similar age (8-12 months) were used for the clinical study. They were randomized into 3 groups (CH1-5, CL1-5 AND AC1-5). Simple transverse femoral fractures were created under anaesthesia using a bone saw. Spatial alignment of the bone was achieved by insertion of an intramedullary pin. Radiographic assessment confirmed that the pins were intact and internal fixation was thorough. Celecoxib (Celebrex® Pfizer Inc, Germany) was supplied in encapsulated powdered form and was suspended in 0.5% dimethylsulphoxide (weight per volume) in sterile deionized water. Each dog in group 1 (CL1-5) was given 5mg/kg Celebrex®, group 2 (CH1-5) 10mg/kg Celebrex® and group3 (AC1-5) 20mg/kg acetaminophen (Divamol®, NDF Pharmaceuticals Ltd, Nigeria) orally three times daily. Drug administration was commenced four hours after the creation of the fracture and was continued daily for the specified number of times for each study groups for two weeks. Sequential radiographs were taken to evaluate fracture healing at week 2, 4, 6, and 8 after surgery. Follow-up radiographs were compared with earlier radiographs to assess the dynamics of fracture healing. Radiographic studies showed that fracture healing was not affected in dogs treated with 5mg/kg (Celebrex®), delayed union was observed in dogs treated with 10mg/kg (Celebrex®) and there was relatively high incidence of non-union in dogs treated with acetaminophen. Celebrex® at a dose of 5mg/kg did not affect fracture callus formation and did not cause a significant increase in the proportion of delayed union fracture. However, it provided adequate analgesia for animals in this study group. Celebrex® at a dose of 10mg/kg reduced the fracture callus formation, significantly increased the proportion of delayed union and it provided the best analgesia in the study groups. Conversely, acetaminophen therapy (20mg/kg three times daily) did not significantly affect callus formation, but increased the proportion of delayed union and non union fractures.