Causes of Warm or Hot Joints

If your joint feels warm or swollen, you may be experiencing inflammation, the immune system's response to an injury or illness. Joint warmth can affect one or multiple joints and you may also have other symptoms depending on the underlying cause.

This article will explore what causes warm joints. It will also explain when to reach out to your healthcare provider, as well as how joint conditions are diagnosed and treated.

What Causes Warm or Hot Joints?

Individuals who have warm joints may also have pain, stiffness, and swelling, also known as inflammation, around the affected area. Inflammation raises your body temperature to help fight infections and heal injuries. Warm or hot joints may be caused by an inflammatory response to:

• Trauma
• Infections
• Rheumatic conditions, which are autoimmune or inflammatory diseases

Traumatic Causes

Joint trauma may affect the structures within the joint, such as the bones, muscles, tendons, ligaments, and cartilage.

Common injuries that may cause warm joints include:

• Dislocation: The partial or full separation of the bones in a joint
• Fracture: Also known as a broken bone
• Sprains: Damaged or partially torn ligaments that hold the bones together
• Strains: Muscle or tendon damage or partial tears that occur due to overstretching

Infectious Causes

Joint infections may be caused by an injury that introduces bacteria or a virus into the body.

Infections that can cause a warm joint include:

• Septic arthritis: A joint infection that may occur as a result of a bacteria or fungus, or from a bloodstream infection
• Lyme disease: A tick-borne illness caused by certain bacteria that leads to joint pain, inflammation, a rash, and flu-like symptoms
• Cellulitis: A potentially life-threatening bacterial skin infection that can cause blisters, pain, and swelling
• Osteomyelitis: A bacterial infection of the bone, seen more often in those with diabetes and sickle cell disease
• Reactive arthritis: A form of arthritis that develops in response to a bacterial infection elsewhere in the body
• Rheumatic fever: An uncommon illness, associated with strep throat or scarlet fever, that causes inflammation in multiple joints

Rheumatic Causes

Rheumatic diseases can cause short- or long-term pain and inflammation in the joints, muscles, or connective tissues. A key characteristic of rheumatic diseases is having flare-ups of symptoms.

Rheumatic conditions that can cause a warm joint include:

• Osteoarthritis: "Wear-and-tear arthritis" that causes joint stiffness, pain, and swelling
• Gout: A very painful type of arthritis caused by crystals of uric acid building up in the joint
• Polymyalgia rheumatica: An inflammatory disorder that typically affects people over the age of 50, and causes pain and stiffness
• Psoriatic arthritis: A form of arthritis that frequently develops alongside the skin condition psoriasis
• Rheumatoid arthritis: An autoimmune arthritis that tends to affect the same joints on both sides of the body
• Juvenile idiopathic arthritis: Arthritis that impacts those ages 16 and younger
  

When Should I See a Healthcare Provider for Warm Joints?

You should seek medical attention if your warm joint doesn't begin to improve within a day, or if you don't know the cause. Your healthcare provider might refer you to a rheumatologist, a doctor who specializes in autoimmune and inflammatory conditions, for further investigation.

How Are Joint Conditions Diagnosed?

In addition to your joint warmth, your healthcare provider will consider your other symptoms and review your medical history, family history, and medications.

They may also do a physical examination to look for joint pain, tenderness, a rash, swelling, or restricted movement.

Based on your history and physical examination, you might need one or more of the following:

• Blood tests: Various blood tests are done to check for inflammation, antibody levels, uric acid, and genetic markers.
• Imaging tests: Ultrasound, X-ray, computed tomography (CT), and magnetic resonance imaging (MRI) can help visualize bone or soft tissue damage.
• Joint aspiration: Arthrocentesis is the removal of fluid from the joint using a needle. It is generally done if the symptoms are severe and an infection is suspected.
• Blood and tissue cultures: The bacterial or fungal organisms causing an infection can be grown and identified in a lab.
• Antinuclear antibody (ANA) tests: Autoantibodies, which are specific proteins associated with an autoimmune process, can be detected in the blood with this test.

How Are Joint Conditions Treated?

Treatment for a joint condition may differ based on whether the cause is traumatic, infectious, or rheumatic.

Joint Injuries

Mild joint injuries may only require rest, restriction of movement, ice application, and a medication such as a nonsteroidal anti-inflammatory drug (NSAID). More serious injuries may require surgery or complete joint immobilization with a splint or cast.

Joint Infections

Bacterial joint infections are usually treated with a combination of antibiotics and a procedure to clean out the joint, either with surgery or repeated removal of joint fluid with a needle. Samples of the joint fluid and/or blood can be tested to help determine which antibiotic medication will work best.

Fungal infections, more commonly seen in those with compromised immune systems, are treated with antifungal medications.

Rheumatic Disorders

Osteoarthritis may be treated with pain medications, as well as physical therapy, exercise, weight management, and ice or heat application.

If the disease progresses, other treatment options include:

• Oral or injected steroid medications known as corticosteroids
• Intra-articular hyaluronic injections, which aim to help lubricate the joints
• Arthroscopic surgery, a procedure that only requires small incisions, to help assess and treat the joint damage
• Joint replacement surgery if the joint is severely damaged

Rheumatoid arthritis and other autoimmune joint disorders may be treated in a similar manner. However, other medications like disease-modifying antirheumatic drugs (DMARDs) and biologic or targeted therapies may also be used.

Summary

Warm or hot joints may be caused by trauma, infections, or rheumatic conditions. Reach out to your healthcare provider if your warm joint does not improve within a day, or if you are unsure of the exact cause. Seek emergency medical treatment if you are in a lot of pain, have a fever, and your joint is swollen or your skin has changed in appearance.

Joint conditions are diagnosed with blood, tissue, and joint fluid tests. Imaging tests may be used to look for bone or soft tissue damage. Your doctor may also take your medical and family history, and give you a physical exam.

Joint conditions are treated in a variety of ways depending on the underlying cause. Treatments may include:

• Rest, ice, medications, and sometime a splint or cast for joint injuries
• Antibiotics or antifungals, and a joint cleaning procedure for joint infections
• Various medications, as well as certain surgeries for rheumatic conditions