Senior Care in Huntington Beach CA: When many people hear the term “psoriasis” they immediately think of the skin symptoms that are related to this condition. As a family caregiver, however, it is important that you understand that this is not the only issue that shares this term. In fact, approximately 30 percent of people who suffer psoriasis will develop a condition referred to as psoriatic arthritis. This condition can be very painful, leading to pain in the lower back and feet, as well as swelling throughout the fingers and toes.