Warmth of a joint occurs in many normal and abnormal settings. Joint warmth can be a result of a warm covering over a joint and be normal. Joint warmth is a normal part of the healing process after surgical replacement of joints (arthroplasty). Injury, including fracture, bruising, and bleeding into a joint can lead to joint warmth. Joint warmth can also be a result of diseases of the joint that cause inflammation. These diseases include arthritis, such as rheumatoid arthritis and psoriatic arthritis, as well as infection directly or indirectly involving the joint, such as from bacteria or viruses.