February 21, 2018

Old Rabbit Paralysis: Part I

Old Rabbit Paralysis Part 1: Spondylosis of the Lumbar Spine and Trauma

Q. We have been told that our bunny has “old bunny paralysis” and nothing can be done. Is this true? What is this and why does it happen?

There are many diseases that can affect the neurological state of a rabbit. It is often necessary to perform one or more diagnostic tests to determine the cause. There are also occasions when the diagnosis in only suggested based on ruling out other causes of disease. Let us look at a list of some of the more common diseases that can result in paralysis or weakness of the pet rabbit. In Part 1 we will look at spondylosis of the lumbar spine and trauma.

Spondylosis of the lumbar spine
This is a fairly common disease of rabbits over 4 years of age, particularly females of medium to large breeds.
Cause: The vertebrae in the lumbar or back area gradually develop little bony protrusions that can eventually bridge to the adjacent vertebrae resulting in the fusion of the two. No one knows the exact reason this happens, but it is likely an aging process. It can be aggravated if a rabbit is carrying excess body weight (obese). This is not life threatening and can progress for years.

Signs: The fusing of the vertebrae decreases the flexibility of the spine and prevents the rabbit from being able to jump and run as easily. Before these bony “spurs” fuse completely, they can rub on each other and cause some pain. The pain may come and go dependent on things such as the weather and how much exercise the rabbit got the day before. Rabbits affected with this disease “shuffle” rather than hop and on some days can become very reluctant to move at all. As the disease progresses, it may be difficult for the rabbit to get in and out of the litter box and he may soil himself.

Diagnosis: The diagnosis is based on finding the bony changes on an x-ray of the spine.

Treatment: There is nothing that can stop the formation or progression of this disease. However, medications can be given to control pain and make the rabbit’s life more comfortable. Medications used may include aspirin, nonsteroidal anti-inflammatory drugs, and corticosteroids. All these medications should be used with caution and only under a veterinarian’s supervision. Some people have reported that their pet rabbits experienced relief with the use of acupuncture. Many also feel it is helpful to regularly massage or apply heat to the back. Gentle massage over the muscled areas of the back only (NEVER directly over the bone) can warm the area and help decrease muscle tightness. If your rabbit enjoys massage, or the application of warmth, then by all means use it. In addition, if the rabbit is obese, it is necessary to reduce the work load on the back by reducing the weight. As the disease progresses, it will be necessary to keep the hind quarters clean from urine and stool and to provide soft, absorbent bedding to prevent bed sores and pododermatitis (foot pad infections). Rabbits with any disease that causes weakness of the hind limbs will not be able to keep their ears clean by scratching. Check the ear canals at least once weekly for excess wax accumulation.

Damage to a rabbit’s back by any kind of trauma can lead to partial or complete paralysis of the hind limbs.

Cause: The most common cause of back trauma is when a rabbit is being restrained and it kicks out suddenly or twists. Even when the best restraint is used, it is still possible for this situation to occur. The force of the kicking or twisting can literally fracture vertebrae (spinal bones) in the back. The fractured vertebrae are then unstable resulting in severe bruising or severing of the spinal cord. Rabbits can also sustain this kind of trauma (although rarely) when running or playing.

Signs: Complete or partial paralysis is immediately evident after the injury. There may be a loss of bladder and bowel control.

Diagnosis: This condition is diagnosed by demonstrating the damaged vertebrae on an x-ray. Occasionally the vertebrae will “snap” out of place during the injury, cause damage to the spinal cord and then go back into place by the time the x-ray is taken. These cases can be difficult to diagnose unless high detail x-ray film is used or a myelogram is done (where dye is injected into the spinal fluid to determine damage to the spinal cord).

Treatment: If the spinal cord is completely severed or seriously bruised, there is no treatment that will return normal neurological function. It is advisable to consider euthanasia for these patients as their quality of life will be very poor. Cases that have only mild to moderate damage to the spinal cord or that still experience some feeling in the toes and maintain bladder or bowel control have a chance of healing. These rabbits should confined to a cage for a period of 6 to 8 weeks to facilitate healing of the fractured bones. It may be necessary to use anti-inflammatory drugs such as corticosteroids for the first few days after the injury. Many of these rabbits will regain at least partial if not total neurological function and live a good quality of life.

Continue To Part II