Some Causes and Features of Pain in a Single Joint

Crystal-induced arthritis (gout and related disorders such as calcium pyrophosphate arthritis )

Sudden and severe pain, swelling, warmth, and decreased range of motion, particularly in the great toe, ankle, wrist, or knee

Sometimes with redness of the skin

Often prior similar episodes of pain that resolved with or without treatment

Withdrawal and testing of joint fluid (joint aspiration) to look for crystals

Sometimes ultrasound, CT, or x-rays

Hemarthrosis (blood in the joint)†

Symptoms may be spontaneous or begin soon after an injury

Usually in a person with a recent injury or a bleeding disorder

Withdrawal and testing of joint fluid (joint aspiration)

Sometimes CT or MRI

Infectious arthritis (for example, a bacterial, fungal, or viral infection or tuberculosis)‡

Sudden and severe pain, swelling, warmth, and decreased range of motion

Sometimes gradual pain and swelling

Withdrawal and testing of joint fluid (joint aspiration)

Injury, such as a fracture or abnormality inside the joint that interferes with joint motion (for example, abnormal joint cartilage due to a torn knee meniscus)

Symptoms begin immediately after injury

Often swelling

X-rays

Sometimes MRI

Sometimes insertion of a viewing scope into the joint (arthroscopy)

Lyme disease

Sudden start of pain in one joint that may move from one joint to another

Usually body aches, fever, and severe fatigue

Usually begins several days to weeks after person had a rash with one or more red blotches with a clear center

Often after a tick bite in an area where Lyme disease is common (tick bite may not be noticed)

Blood test for antibodies against Borrelia burgdorferi, the bacterium that causes Lyme disease

Osteoarthritis

Slowly progressive pain in older people or young people who frequently stress the affected joint (for example, doing manual labor or high-impact sports)

X-rays

Osteonecrosis†

Joint pain in people who have taken or currently take corticosteroids or who have sickle cell disease

X-rays plus MRI

Psoriatic arthritis

Can cause pain in a single joint, usually with swelling (more often causes pain in several joints)

Usually in people known to have psoriasis

Sometimes x-rays

Tumor

Slowly progressive joint pain usually with swelling

Often pain at night

X-rays and MRI