Dog Ear Injuries

Structure of the Ear

• A dog's ear consists of three parts that function as a whole to allow the animal to hear and balance itself properly. The outer ear, or pinna, is the long, external flap that either hangs down or stands up depending on the breed of the dog. Included as part of the outer ear is the external auditory canal, a curved tube that leads from the flap to the tympanum (the eardrum). The outer ear, including the eardrum, has two main functions -- first, to protect the middle and inner ears from injury and disease, and second, to direct sound waves into the part of the ear that distinguishes sound.

  The middle ear is a small, air-filled cavity behind the tympanum consisting of epithelial (skin) cells. It is filled with the auditory ossicles, the smallest bones in the dog's body. The malleus, incus and stapes (commonly referred to as the hammer, anvil and stirrups) constrict sound waves from the outer ear and move them into the inner ear.

  The inner ear consists of two structures: the bony labyrinth and the cochlea. The bony labyrinth contains the lymph fluids, sensory neurons and cranial nerves necessary for equilibrium. The cochlea is a bony, spiral canal filled with tiny cilia (hair cells) and lymph fluids that convert sound waves into mechanical energy that is then transported by auricle nerves to the brain. The brain records this energy as sound.

Traumatic Injury &Treatment

• The pinna (ear flap) is most susceptible to traumatic injuries, either because the dog gets it caught in or on something or because of bite wounds from other animals. If the wound is superficial, without any large or deep punctures or tears, veterinarians will often recommend that owners clean the ear at home with some kind of antiseptic solution, then wrap the ear until it stops bleeding. If the wound appears long and/or deep, veterinary care is essential to prevent infection and help the ear heal. The pinna may need stitching, and the veterinarian will want to examine the eardrum to make sure it is still intact. Most vets will also prescribe some sort of antibiotic medication.

Parasitic Injury &Treatment

• The most common parasites of the dog's ears are yeast and ear mites. In a dog with "yeasty" ears, both the underlying skin of the pinna and the external canal become swollen and inflamed, and owners will smell a bread-like odor coming from the ear. Ear mites can often be seen by the naked eye in the ear canal, which becomes filled with a brown-black, crusty exudate. Both conditions are extremely irritating and will cause dogs to scratch at their ears and face, eventually developing wounds. A veterinarian will need to examine ear scrapings under a microscope to diagnose and treat both the parasites and the wounds.

Considerations

• Because a dog's ears are extremely vascular, wounds will often bleed freely for a long time. Veterinarians will commonly recommend an Elizabethan collar to prevent the animal from scratching or pawing at the ear and reopening the wound. Owners are also encouraged to try to keep dogs from shaking their heads for the same reason. Some dogs may develop a large blood blister called a hematoma on the pinna that will need veterinary treatment.

Warning

• Ear injuries in dogs are rarely fatal and easily treated. However, without veterinary care, infection is very common. If left untreated, infections of the ear can lead to hearing loss and systemic sepsis, which is commonly fatal in injured, neglected animals.