From Pet Health Learning Center
Limping in young cats is very common and usually will take about a week to resolve itself. Kittens have no fear and can strain, sprain or bruise themselves doing their playful acrobatic stunts. If however the limping does not resolve in that week, you should make an appointment with your veterinarian.
The cause of limping can be something as simple as the cat needing a nail trim or it can be more complex and studies need to be done. If upon full examination, the veterinarian cannot determine the exact cause, x-rays may be taken. Both of the affected limbs will be x-rayed to see if there is a difference in their structure. It sometimes takes awhile for changes to be noted on the films, and for that reason, both limbs will be done.
At Home Care
If you notice your cat limping, check their paws closely for any Cat Paw Injuries. There may be some stickers in them that are causing favoritism of the limb. If your cat has thick hair between the pads, this may cause limping as well. Check also for any cuts and Bite Wounds on Cats. Busy cats can get into mischief and may have received a cut on their pad. Something as simple as a mild abrasion from pavement will be enough to cause a limp.
Most cuts on your cat will heal without stitches. It is just important to keep the area as clean as possible. Some Betadine can be used to soak the limb several times each day or a diluted hydrogen peroxide can also be used.
It is important to keep paws dry while they heal. Bandages are a source of moisture and bacteria and are likely to become chewed by your cat. Keep the wound clean and dry.
Any deep puncture wounds will most likely need antibiotics. If you apply ointments, chances are good that your cat will lick it off before it can work.
Arthritis Can Cause Limping
It is possible, especially in older cats, that they have some arthritic joints. If your cat has a limp that doesn't resolve itself fairly quickly or returns intermittently, you need to seek the advice of your veterinarian.
Cats that are extremely active, larger cats and those with inherited problems can also have Cat Arthritis. Diagnosis is made by x-ray, again with both limbs being checked.
It is possible that it could also be a flap of cartilage that has come loose and lodged in the joint. This can be very painful.
Cat Bug Bites, such as tick bites, and spider stings can cause your cat to limp. Snake bites and Cat Bee Stings will also fall into the same areas. If your cat has a reaction other than some irritation and swelling, you need to contact your veterinarian. This is even more important with snake bites, if you cannot identify the type of snake that bit your cat.
Back injuries can cause limping and Cat Back Pain; often this is mistaken for limb lameness. De-claw surgery that was not done correctly can cause severe pain in your cats. If a small portion of the root of the nerve is left, it can be extremely painful.
If you are unsure of the cause, it is always best to call your veterinarian.