Yes, dogs get arthritis too. It is estimated that over 10 million dogs have been diagnosed and 31% of owners state that it is an a real problem for their pets. Canine arthritis is most common in older and large breed dogs since they will put more weight on their joints than the smaller pets. However don't overlook the signs of arthritis in any size pet as they get older.
Pain and discomfort is the same for pets as it is for humans, cartiliage breaks down around the joint in them as it does in us humans. The same medication glucosamine and chrondroitin work for pets as well as humans in relieving pain. MSM also works beautifully for dogs with arthritis. There are an assortment of pet foods that already include these supplements for the older pet.
Remember that your pet cannot speak to you about what ails him, so keep an eye on your pet and recognize the signs of pain.