Weak Hind Legs and Paraplegia
by Debbie Ducommun
of the hind legs in rats can occur suddenly or gradually. Sudden onset can be caused
by an injury to the spine, a subluxation (displacement) of a vertebra, or a
blood clot in the spine. An x-ray might be helpful in identifying displacements
of the vertebra but not soft tissue injuries, such as bruising. An
anti-inflammatory can help an injury. A chiropractor who is willing to work on
animals, or a veterinarian who knows chiropractic, can help in cases of
subluxation. My chiropractor has successfully treated 3 of my rats for neck,
jaw or back problems. (In
In elderly rats, the muscles of the hind legs can weaken but this doesn’t usually affect how the rat walks. If a rat has trouble lifting his hind legs to walk then the rat has a disease. The most common cause is spinal nerve root degeneration (SNRD) of the ventral spinal nerve roots (nerves exiting the spinal cord which govern motor control). This usually progresses slowly over a period of several months. We do not know the cause, but it might be a deficiency of B vitamins. It is common for one leg to be affected more than the other. This condition isn’t painful or life threatening, and the rat usually learns how to get around even with the disability. Even if the hind legs become completely paralyzed, the rat can still lead a comfortable life.
The second most common cause of gradual hind leg paralysis is a pituitary tumor. (See Tumors.) This usually occurs over a few weeks. Two other rare causes are a spinal tumor (I know of only one case) and arthritis of the spine.
B vitamins, especially vitamin B12, are important to the proper functioning of the nerves, and a supplement has reversed or slowed the progression of SNRD in some of my rats. It could be that some rats have a higher need for this nutrient as they age. I recommend all rats over 1½ to 2 years of age get a vitamin B complex supplement, and especially if you notice that a rat is walking funny with her back legs. B vitamins are also good for respiratory disease.
You can buy a human liquid vitamin B complex supplement from a health food store. Give the rat enough of the liquid to supply 10 mcg of vitamin B12 twice a day. The vitamins can be given plain or mixed with food, Ensure, baby formula or some other flavoring.
To figure out the dose, divide the amount of B12 in the human serving by 10 mcg to see how many rat doses are in the human serving. For instance, if there are 50 mcg/ml, then 1 ml contains 5 rat doses, so the dose for a 1-lb rat is 0.2 ml. A more concentrated brand might have 1200 mcg/ml, which is 120 rat doses. A formula this concentrated needs to be diluted. If you add 11 ml of flavoring to 1 ml of this product, the 1-lb rat dose is then 0.1 ml.
Care for Paraplegic Rats
Most rats get along just fine with some paralysis, and don’t seem to suffer. Some extra care will help to maintain their quality of life. You may need to switch to soft food when the patient can no longer hold food in his hands. Soaking rat blocks in water, soy milk, or a liquid supplement such as Ensure makes a mush that is easy for a paraplegic rat to eat. You can break the blocks up with a hammer or nutcracker, so they will absorb the liquid quicker.
Move a paraplegic rat to a one-level cage. If your rat likes a hammock, you can lower it to almost floor level. You can also create a comfortable, floor-level nest away from their potty areas with soft fabric.
A paraplegic rat will usually need modified bedding in his cage, and you may need to clean the cage more frequently. In an aquarium or deep-bottom cage, a layer of aspen shavings at least 3" thick can work well. With a thinner layer of loose bedding, he will tend to push the bedding away as he tries to pull himself around and can end up laying in a puddle of urine. A thick fabric pad such as those sold for dogs to sleep on will stay flat instead of bunching up and will allow the rat to pull himself along. If the rat gets wet with urine, you can pin a human incontinence pad (underpad) on top and change it as needed.
Any urine on the skin must be washed off, sometimes more than once a day, or it will burn the skin. You can hold your rat under the faucet with warm water, with maybe a little soap and then pat dry. If the urine still causes his skin to become red and irritated, you can treat it with Rescue Remedy Cream (available at health food stores) rubbing in it liberally.
You might also need to help groom your rat. You can brush him with a toothbrush, or wipe him with a damp cloth or baby wipe if needed. Most paraplegic rats also like you to scratch the areas they can no longer reach with their feet.
You may need to clean wax out of your rat’s ears with your little fingernail or a cotton swab. You may need to clean a male’s penis of waxy build-up daily by gently pressing down on either side of the penis to pop the waxy plug out. You may need to wipe a female’s vaginal area of discharge. Rats with a reduced activity level, especially those with some paralysis, usually need their toenails trimmed regularly.
Rat Fan Club