Interlocking nail treatment of diaphyseal long-bone fractures in dogs

Objective-To determine results of using interlocking nails (IN) for fixatio n 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 co mminuted 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 g raft were used at the surgeon's discretion. Participating surgeons provided information on age, sex, weight, and breed of the dog, details of the surg ery, 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 remaini ng 126 dogs (83%), fractures healed without complications. For these 105 do gs, limb function was excellent (n = 90), good (12), fair (2), and poor (1) . Complications developed for 21 dogs (17%); limb function after additional treatment was excellent (n = 10), good (2), fair (5), poor (1), or unrepor ted (3). Interlocking nails broke in 9 dogs; breakage was attributed to fat igue failure because of use of too small an IN or because of insertion of t he IN so that a screw hole was positioned at the fracture site. Clinical Implications-The high success rate and low complication rate sugge st that IN can be used to stabilize diaphyseal fractures in dogs. Good tech nique is necessary for optimal results.