Interlocking nail treatment of diaphyseal long-bone fractures in dogs

Abstract

Objective - To determine results of using interlocking nails (IN) for fixation of diaphyseal long bone fractures in dogs. Design - Multi-center prospective clinical trial. Animals - 134 dogs with diaphyseal fractures of the femur (n = 92), tibia (23), or humerus (19); 11 had previous unsuccessful treatments, and 103 had comminuted fractures of which 70 were classified as unstable. Procedure - All fractures were stabilized with 6-or 8-mm-diameter IN with 3.5-or 4.5-mm screws, respectively. Cerclage wires and an autogenous bone graft were used at the surgeon's discretion. Participating surgeons provided information on age, sex, weight, and breed of the dog, details of the surgery, details of any intra-or postoperative complications, fracture healing time, and limb function. Results - Eight dogs were lost to follow-up evaluation. In 105 of the remaining 126 dogs (83%), fractures healed without complications. For these 105 dogs, limb function was excellent (n = 90), good (12), fair (2), and poor (1). Complications developed for 21 dogs (17%); limb function after additional treatment wasexcellent (n = 10), good (2), fair (5), poor (1), or unreported (3). Interlocking nails broke in 9 dogs; breakage was attributed to fatigue failure because of use of too small an IN or because of insertion of the IN so that a screw hole was positioned at the fracture site. Clinical Implications - The high success rate and low complication rate suggest that IN can be used to stabilize diaphyseal fractures in dogs. Good technique is necessary for optimal results.