There are three primary classifications of bone fractures with numerous subtypes. All of which will require an individual assessment by the veterinarian to ensure proper healing. While most “simple” fractures are not technically an emergency, any animal that is suspected of breaking a bone should be seen quickly by the doctor, at least for the sake of pain control. After an examination and an x-ray, the veterinarian will determine the best course of treatment.
Closed fractures involve a broken bone without a break in the skin. There has been no contamination of the wound, in other words. Unless an organ or artery has been damaged, these fractures can usually wait a few days to be repaired. Open or compound fractures have bone protruding through the skin or a puncture that communicates with the bone. These types of injuries are susceptible to infection, and should be dealt with quickly and aggressively. Bone infections can be especially difficult to treat, and healing of the fracture can be significantly delayed. Epiphyseal (e-pif-uh-see-uhl) fractures occur at the site of a growth plate. Growth plates are the soft, spongy ends of the bone in juvenile animals that allow the bone to elongate as the animal matures. These types of fractures are notorious for healing improperly, causing irregular bone growth or deformity if not repaired properly.
Another type of fracture that would warrant emergency medical treatment would be that of the vertebrae, a broken neck or a broken back. If there is impingement on the spinal cord, the injury could lead to paralysis.
Subtypes of fractures are basically descriptions of the physical break pattern on the bone. Simple fractures describe bones that are broken into 2 or 3 large fragments, whereas comminuted fractures cause shattering of the bone into many tiny pieces. There are also compression fractures, spiral fractures, transverse, oblique, impacted fractures, and so forth…
If a bone in a limb is fractured, the animal will not bear weight on that leg at all. Other fractured bones may not cause such obvious symptoms. An x-ray can reveal even a green-stick fracture – an incomplete break that does not go completely through the bone. It is important to have any pet suspected of a fracture assessed by the veterinarian to ensure that should one exist, it can be repaired correctly so that it will heal properly and not cause complications later in life.
Before attempting to move a pet with a fracture, be sure to securely fasten a muzzle to keep from being bitten. If there is active bleeding, apply firm direct pressure with your hand or a towel. If there is an open wound, lightly wrap it in gauze or cloth to avoid further contamination. If possible, immobilize the animal on a board or stretcher, especially if the back or neck seems to be injured. Do not attempt to splint a broken bone at home. Inappropriately applied homemade splints can actually do more harm than good. Instead, padding the affected bone with a large towel or blanket will help immobilize the fracture and reduce pain. Never give over-the counter pain medications to your pet. They can cause extended bleeding times and many are quite toxic to animals.
In the case of very minor fractures, the veterinarian may be able to apply a splint. In many cases however, surgery may be necessary to properly align and stabilize the bone. In any case, the goal of treatment is to fix the two ends of the fracture so that they cannot move, allowing them time to heal. If the animal becomes too active too soon after surgery, this may cause a separation of the repaired fragments which may result in a non-union – the fractured ends not healing back together.
There are as many surgical repair techniques as there are types of fractures. In general, a surgical-grade stainless steel appliance will be utilized to hold the bone in place while it heals. Kershner wires or bone pins are heavy gauge steel rods that are drilled into the medullary canal, the center hollow portion of a bone where the marrow lies. Bone plates are affixed using screws drilled transversely through the outer walls of the bone. External fixators consist of pins drilled through the skin and bone and are held together by a stainless steel clamp outside the body. Which type of appliance is used is determined by the size of the bone, the location in the body, the complexity of the fracture, and the expected healing time of the injury.
K-wires and bone plates are typically left in place after the fracture completely heals, but in certain circumstances they have to be removed. This is true especially if infection or inflammation develops at the site of repair. External fixators are always removed.
Plaster and gauze or fiberglass casts are not used on dogs and cats for one simple reason: the animal cannot tell the doctor what is going on under the cast. If irritation or infection develops, it will not be revealed until the cast is removed. By that time, disastrous effects may have already occurred.
In general, bones take weeks to heal. During that time, the animal should have restricted activity, and your veterinarian will give you detailed instructions on aftercare.