Chronic pain: osteoarthritis and cancer.

Osteoarthritis and cancer pain are two types of chronic pain commonly seen in small animal practice. The management of osteoarthritic pain consists of both pharmacologic therapy and nonpharmacologic strategies, including exercise control, dietary management and surgical therapy. Nonsteroidal antiinflammatory drugs are commonly used, although there is still controversy about their effect on the underlying pathologic processes of osteoarthritis. Despite a lack of well-designed clinical trials, chondroprotective drugs and neutraceuticals have gained popularity. Cancer pain can result from direct tumor invasion, paraneoplastic syndromes or diagnostic and therapeutic procedures, including surgery, chemotherapy and radiation. Treatment of cancer pain consists of definitive or palliative therapy and management of therapy induced pain. Analgesic therapy should be based on the World Health Organization's three step analgesic ladder for the administration of analgesia to cancer patients.