Connective tissue includes joints, tendons, cartilage, collagen, muscles and skin. There are a number of connective tissue diseases; rheumatoid arthritis, scleroderma, Sjogren's syndrome, Raynaud's phenomenon, vasculitis, polymyositis and dermatomyositis. It is not uncommon for a person to have symptoms that indicate a connective tissue disease, but not enough symptoms to clearly specify a particular disease.