General Fracture Information in Cats
Diagnostic tests, which may be needed to recognize or treat fractures, include:
Complete medical history and physical examination
Because of the abnormal movement that occurs in a limb at the fracture site, the diagnosis of a long bone fracture is usually very obvious. Your veterinarian will initially want to ignore the obvious fracture and evaluate your cat for other injuries. Some injuries (particularly those of the chest and spine) necessitate prolonged evaluation before any surgery is done.
Thoracic radiographs (chest X-rays) are important in animals that sustain trauma. Potentially life-threatening pulmonary contusions (lung bruising) or pneumothorax (free air in the chest space from a small lung rupture) is frequently encountered in patients who have been involved with automobile accidents or other trauma. Many times patients suffering from pelvic fractures also have injury to the urogenital system. Abdominal radiographs (X-rays) or special studies involving the injection of dye or contrast material may be necessary to evaluate the kidneys, ureters and bladder fully.
Blood tests may detect the presence of anemia or other problems related to shock. Blood gas and electrolyte tests enable your veterinarian to evaluate the metabolic status of your pet. Biochemical profiles look at the function of major organs, such as the liver and kidneys. These tests are helpful in assessing whether a patient is an acceptable risk to undergo anesthesia for definitive fracture repair.
A Robert Jones-type padded bandage or a splint represents excellent methods to temporarily stabilize fractures of the radius/ulna (front leg) or the tibia (lower, back leg). This type of device can be used to prevent excessive motion at the fracture site while the patient is stabilized prior to definitive surgical repair. The “bulky” nature of this type of “pillow splint” provides support to these fractures and the damaged soft tissues around.
It is important to realize that there may be more than one acceptable method for repairing a specific fracture. Often the experience of the surgeon determines the specific fracture repair.
A comminuted fracture is defined as one that has more than two major fracture fragments. These fractures are inherently unstable. Fractures involving a joint require specific repair methods that allow early motion in the affected joint. Forces act at fracture sites needing stabilization and occur in the direction of the bone, perpendicular to the bone (bending or shear) or around the bone (rotational or torsional).
Many factors come into play when deciding definitive fracture repair. The type of repair undertaken must stabilize distracting forces.
Fractures that are inherently stable (such as a simple fibular fracture) may just require stabilization with a cast or splint. Using pins and wires is another method of stabilizaton.
To provide additional support, a supplemental external skeletal fixator (ESF) can provide additional axial and rotational stability. Besides placing a pin internally within the marrow cavity, pins are placed through the skin and into the bone fragments. The pins are attached with a series of clamps and connecting bars to provide stability that is more rigid.
Veterinarians have used bone plates and screws for the past 30 years. Plates and bone screws generally provide superior rigid stability to fractures but, many times, this is at the expense of the regional blood supply. Extensive dissection of the bone fragments is often necessary to achieve proper fixation. In recent years the trend among veterinary orthopedic surgeons is to dissect less tissue and provide an environment for “biologic fixation.” Many times fractures are fixed in a closed manner with an ESF as the definitive method of fixation. Generally, only minimal tissue dissection is required with these techniques.
More recently, the use of interlocking nails has been used in veterinary orthopedic surgery. This technique employs a large intramedullary (within the bone cavity) “pin” that is modified to accept locking screws through the bone and nail both above and below the fracture. This provides very secure fixation with minimal tissue invasion.
Follow-up Care for Cats with Fractures
It is very important to follow your veterinarian’s instructions concerning postoperative care. Make sure all your questions are answered before leaving the hospital with your pet.
If your pet has had surgery performed, pay particular attention to the wound looking for excessive redness, swelling or discharge. Be sure to alert your veterinarian if any of these conditions occur.
Follow your veterinarian’s directions for follow up examinations. Radiographs (X-rays), are usually taken at 4 to 6 week intervals, until the bone is healed.
Physical therapy may be helpful in the early rehabilitative process, and your veterinarian should provide explicit instructions. Your veterinarian may have “prescribed” a certain amount of physical therapy following fracture repair. Many times the success or failure of a specific fracture is dependent on the type of aftercare provided.