Casts, external fixators, and bone plates can all be used to help heal broken bones.
“Pets most commonly wind up with broken bones from some sort of trauma, often getting hit by a car,” says Dr. Tisha Harper, a veterinarian at the University of Illinois Veterinary Teaching Hospital in Urbana, who is board certified in small animal surgery. “However, smaller breed dogs with little legs can break bones by just jumping off the couch.”
How do you know if there is a broken bone?
“If an animal is limping, holding its leg awkwardly, or if swelling or pain is noticed when a limb is touched, the animal should be taken to the veterinarian for assessment,” advises Dr. Harper. “If an animal has an open fracture, meaning there is a wound present and the bone is exposed, cover it with a clean, dry cloth to prevent further contamination of the bone and go to the clinic immediately.”
Fractures are very painful, so Dr. Harper advises owners to handle the pet with great care. A normally sweet pet may respond to pain by biting.
Dr. Harper explains that the process of fixing a broken bone in a pet starts with taking x-rays to determine where the bone is broken and how many pieces it is in. Fractures can be stabilized in a variety of ways, and the veterinarian must take into account the age of the patient when deciding how to stabilize a fracture.
For example, animals can have a cast on a limb just like people do. According to Dr. Harper, a cast would be an appropriate method to stabilize a broken bone if the fracture is simple and minimally displaced, located below the elbow or knee, and the animal is young. She says that a cast on a young animal will have to be changed periodically, because the animal will grow out of it. To be effective, the cast must stay clean and dry and the pet must be prevented from chewing on it.
Disadvantages of a cast include that it will not provide as much rigidity as other methods, such as an external fixator or bone plate, and that it immobilizes joints, leading to stiffness and requiring physical therapy for the pet to regain full motion of the joint.
Another way to fix a broken bone is by using what is called an external fixator. With this approach, the veterinarian will place pins through the skin and into the bone. These pins are connected externally by clamps and connecting bars or an acrylic column. This method provides rigid immobilization of the bones to allow the fracture to heal, while allowing the patient to use the limb in a normal way.
“A big advantage of an external fixator is that the placement and removal of the apparatus is minimally invasive,” notes Dr. Harper. “There is no surgical approach to the fracture site, and the soft tissues surrounding the fracture can be preserved. The patient just needs to be sedated, and the fixator can be removed or adjusted as needed.”
So how does a veterinarian determine when surgery is needed for a patient with a fracture?
Dr. Harper explains that this depends on the location of the fracture, the age of the patient, whether the skin is intact or there is an open wound, how many fragments the bone is in, and whether the animal has other orthopedic issues.
Typically a surgical repair involves bone clamps used to put the bones back in normal alignment. A bone plate can also be used, in which screws attach a plate to the bone. Pins are sometimes placed in the bone marrow cavity to help with the alignment, and the surgeon can also use wires.
According to Dr. Harper, most breaks heal in about 8 to 12 weeks, whether a cast, external fixator, or bone plate is used.
For more information about fracture repair, contact your local veterinarian.
By Sarah Netherton