Overview of Feline Maxilla Fractures
Fractures of the maxilla (upper jaw) are usually the result of major trauma, but can be caused by disease of the bone itself or dental disease.
Fractures of the maxilla are often segmental involving a short region of the upper dental arcade. The fractures can be impacted (pushed inward) resulting in disruption of the adjacent nasal cavity. Maxillary fractures infrequently result in instability. These fractures are usually “open” (bone exposed) and “comminuted” (multiple bone fragments). Depending on the nature of the fracture and the age of the animal, different methods of management may be indicated for each situation. Maxillary fractures can have serious complications if repair is indicated but not performed or if the repair fails.
What to Watch For
Diagnosis of Maxilla Fractures in Cats
Thorough physical examination including examination of the oral cavity is initially performed. No laboratory tests are required to make the diagnosis, but several additional tests may be needed, including:
Treatment of Maxilla Fractures in Cats
Emergency care for concurrent problems caused by the trauma is initially performed prior to specific treatment for the maxillary fracture. After stabilization, additional treatment may include:
Home Care and Prevention
With conservative management or after surgical repair of the fracture, the cat will be kept restricted from activity for several weeks and will be fed only a soft gruel that does not require chewing.
Recheck appointment with the veterinarian will occur in several weeks to evaluate how the bone is healing (possibly with new radiographs), to monitor the animal's progress, and to make sure it is safe to return the animal to his regular diet.
Many traumatic events are true accidents and thus unavoidable. Dental hygiene and routine cleaning by the veterinarian may prevent severe dental disease that could lead to maxillary fractures.
In-depth Information on Maxilla Fractures in Cats
Motor vehicle trauma is a frequent cause of maxillary fractures in cats but any trauma to the head can cause them. Cats can develop non-traumatic fractures of the maxilla when certain disease conditions exist. These fractures, also known as “pathologic fractures” can occur if the cat has severe dental disease leading to destruction of the bone supporting the teeth, has a bone infection (osteomyelitis) or has cancer of the bone.
Symptoms caused by fracture of the maxilla may be relatively subtle, with reluctance of the animal to play or chew on toys or food or more obvious with bloody saliva dripping from the mouth, bloody fluid coming from the nostril, reluctance to close the mouth, or inability to eat at all.
The maxilla is actually a relatively thin and frail bone that forms the outer wall and floor of the nasal cavity (also known as the roof of the mouth or hard palate) and supports the upper canine, premolar and molar teeth on each side of the mouth. Because of the configuration of the maxilla in relation to the rest of the skull, fractures usually are comminuted (multiple pieces) and impacted into the nasal cavity. Sometimes the fractures are not displaced and are relatively well aligned with the remaining bone. Because there is relatively little soft tissue covering the maxilla in the mouth, these fractures are usually “open” (bone exposed). Open fractures have a greater chance of getting infected and may have more complications than closed fractures.
Each case of maxillary fracture needs to be evaluated in its entirety (age of animal, severity of the fracture, experience of the surgeon, and financial concerns of the owner) to determine the most appropriate and best form of treatment.
Inappropriate case management, inadequate surgical stabilization when indicated or poor aftercare can lead to complications such as non-unions (fractures that will not heal), malunions (fractures that heal in an abnormal direction or orientation resulting in malocclusion of the teeth and difficulty chewing or impairment of airflow through the nasal cavity) or osteomyelitis (bone infection).
A thorough physical examination is very important to make sure your pet is not showing signs of hypovolemic shock secondary to the trauma or blood loss. It is also important to make certain that there are no other injuries present. No laboratory tests are required to make the diagnosis. After stabilization, additional tests may include:
Based on the location and severity of the fractures, a more informed discussion with the owner can occur regarding potential treatments, prognosis, and costs.
Emergency care for concurrent problems is paramount. Shock is a frequent result of major trauma and must be treated quickly. Treatment for shock involves intravenous fluid administration to maintain blood pressure and adequate oxygen delivery to the body. Injury to the lungs and chest cavity are also commonly seen after major trauma and may require supplemental oxygenation or removal of free air (pneumothorax) from around the lungs. After stabilization, other treatments may include:
Follow-up Care for Cats with Maxilla Fractures
After discharge from the hospital, the cat must be restricted from activity for several weeks to allow the fracture time to properly heal. The duration will vary depending on the severity of the injury and any concurrent injuries the animal may have. Restricted activity means that the cat should be kept confined to a carrier, crate, or small room whenever he cannot be supervised. Play and rough-housing should be avoided, even if the cat appears to be feeling well. It is especially important that cats with maxillary fractures not be allowed to chew on toys or other objects and be fed only soft food or blenderized gruel.
Fractures that are repaired with internal fixation (wires or bone plates and screws) will have a skin incision on the face that needs to be monitored daily for signs of excessive swelling or discharge. These can indicate problems with the incision or possibly infection.
Analgesics (pain medications) or anti-inflammatory medication should be given as directed by the veterinarian. Analgesics, such as butorphanol (Torbugesic®) can cause sedation, and anti-inflammatory drugs, such as aspirin can cause stomach upset. Your veterinarian should be informed if any adverse side effects do occur.
If at any point prior to the follow-up evaluation the cat stops eating after some improvement following surgery, or if a bad odor begins coming from the mouth, there could be a problem.
Several weeks after surgery a follow-up appointment will be needed. The skull occasionally may need to be X-rayed again to make sure the bone is healing properly. If healing has occurred as expected wires placed around the teeth will be removed and the animal's activity level and diet will be allowed to return to normal.
In general, any other implants that were used in the repair under the skin will be left in place unless they cause a problem at some point in the future. Potential problems can include migration (movement) or infection of the implants.