Diseases & Conditions
Children sometimes complain about aches in their joints. A joint is where the ends of bones meet, such as the knee joint, shoulder joint, or the small joints in the fingers and toes.
Joint pain in children can be caused by a variety of things. But if a child's joints are swollen for 6 weeks in a row or longer, they may have chronic arthritis. Causes of chrnoic arthritis include juvenile arthritis, as well as other conditions like lupus or dermatomyositis.
Juvenile arthritis, or juvenile idiopathic arthritis (JIA), is a long-lasting, chronic disease. It is the most common form of arthritis in children. In the United States, it affects nearly 300,000 children under the age of 18.
There are several types of juvenile arthritis. Nearly all of them are different from rheumatoid arthritis in adults. This is why the term "juvenile rheumatoid arthritis (JRA)" is no longer widely used.
Juvenile arthritis is a disease of inflammation. This means that inflammation in the body attacks healthy cells and tissues. Arthritis results from ongoing joint inflammation in four steps:
- The joint becomes inflamed
- The joint stiffens (contracture)
- The joint suffers damage
- The joint's growth is changed
In some cases, symptoms of juvenile arthritis are mild and do not progress to more severe joint disease and deformities. However, untreated juvenile arthritis can produce serious joint and tissue damage. It can also cause problems with bone development and growth.
For a long time, it was believed that many children eventually outgrow juvenile arthritis. Now it is known that the majority of the children diagnosed with juvenile arthritis will continue to have active arthritis 10 years after diagnosis unless they receive aggressive treatment.
Types of Juvenile Arthritis
There are several types of juvenile arthritis. This classification is based on:
- The number and types of joints involved
- The presence of certain markersin the blood
Doctors classify juvenile arthritis to help them predict how the disease will progress.
Several of the main types of juvenile arthritis are:
Oligoarticular means "few joints." In this type of juvenile arthritis, just a few joints are affected. About 50% of children with juvenile arthritis have the oligoarticular type. Girls younger than 8 years of age are more likely to develop it.
In half of children with oligoarticular juvenile arthritis, only one joint is involved, usually a knee or ankle. This is called monoarticular juvenile arthritis. In some cases, this arthritis may require only mild treatment.
For some children, this arthritis affects four or fewer larger joints. Joints commonly affected include the knees or ankles. Involvement of fingers or toes is unusual.
Oligoarticular juvenile arthritis may also cause eye inflammation. To prevent blindness, your child will need regular eye examinations from a doctor who specializes in eye diseases (ophthalmologist). Eye problems may continue into adulthood.
About 30% of children with juvenile arthritis have the polyarticular type. This type of arthritis is more common in girls than in boys.
Polyarticular juvenile arthritis affects five or more joints, including both larger joints (knees and ankles) and smaller joints (hands and feet). Often, both sides of the body are affected.
Children with a certain marker, or antibody, in their blood, called IgM rheumatoid factor (RF), often have a more severe form of the disease.
Antibodies are proteins in the blood usually used by the body to fight off infection through an immune response. In this form of arthritis, the IgM RF antibody attacks the body's own tissues. Doctors believe that this is the same type of arthritis as adult rheumatoid arthritis and can require more significant treatment.
With psoriatic arthritis, children have both arthritis and either:
- A skin disease called psoriasis
- A parent or sibling with psoriasis
These children can also have nail changes, as well as diffuse swelling in a toe or finger called dactylitis. In some cases, just a few joints are involved; in others, several joints are affected, including both small and large joints.
Enthesitis-related arthritis is a form of juvenile arthritis that often involves inflammation of tendons and ligaments, as well as joints. It may also affect the spine.
Children with this type of arthritis sometimes have joint pain without any obvious swelling and may have back pain. Often, the inflammation in the back occurs later in life.
Enthesitis-related arthritis most commonly affects boys over the age of 6.
About 20% of children with juvenile arthritis have the systemic type.
Systemic juvenile arthritis causes swelling, pain, and limited motion in at least one joint. Additional symptoms include rash and inflammation of internal organs such as the heart, liver, spleen, and lymph nodes. A fever of at least 102° every day for 2 weeks or longer suggests this diagnosis.
If not adequately treated, children with systemic juvenile arthritis can develop macrophage activation syndrome, a severe condition that causes multi-organ dysfunction. Untreated, this condition can be fatal.
No one knows exactly what causes juvenile arthritis. Researchers believe some children have genes that make them more likely to get the disease. Exposure to something in the environment (for example, a virus) may triggerjuvenile arthritis in these children. Juvenile arthritis is not usually hereditary, so it is very rare for more than one child in a family to get it.
Juvenile arthritis affects each child differently and can last for indefinite periods of time:
- There may be times when symptoms improve or disappear (remissions).
- There are other times when symptoms worsen (flare-ups).
- Sometimes, a child may have one or two flare-ups and never have symptoms again.
- Other children may have frequent flare-ups and symptoms that never go away.
The most common symptoms of juvenile arthritis include:
- Painful joints in the morning that improve by afternoon. Sometimes, the first sign of the disease is a morning limp, caused by an affected knee. Hands and feet may also be affected.
- Joint swelling and pain may also be noted. Although young children may not complain of pain, a child may feel irritable or tired and not want to play. Sometimes, juvenile arthritis causes lymph node swelling in the neck and other parts of the body.
- Joints may become inflamed and warm to the touch.
- Muscles and other soft tissues around the joint may weaken from disuse if the child is not able to run and play normally.
- In certain cases, children have a high fever and light pink rash, which typically appears only during the fever episodes.
- Some children develop growth problems. Joints may grow too fast or too slowly, unevenly, or to one side. This can make one leg or arm longer than the other. Overall growth also may slow.
- Some children with juvenile arthritis have eye problems, called uveitis. This is treatable by an ophthalmologist (eye doctor). The presence of eye findings on exam by a specialty-trained ophthalmologist confirms the diagnosis. Without treatment, uveitis can result in eye damage that cannot be cured. Most patients do not have any symptoms, and the only way to diagnose this early is by slit lamp examination performed by an eye doctor.
Early diagnosis and treatment can help to:
- Control inflammation
- Relieve pain
- Prevent joint damage
- Maintain a child's ability to function
Your child's doctor will order a wide range of tests. A complete medical history and physical examination, as well as blood tests, will help the doctor rule out other conditions that cause arthritis.
Other tests, such as X-rays, ultrasounds, and magnetic resonance imaging (MRI) scans, are sometimes used.
Your child's doctor will review your child's complete medical history. They will want to know:
- How long your child has had problems with joint pain and swelling
- Whether the symptoms have gotten better or worse
- Whether your child feels stiff when getting up after rest
The doctor will look for other causes of the symptoms, such as:
- An injury
- Another illness (e.g., infections, cancers, or other autoimmune disease)
- A family history of autoimmune disease
Your childs doctor will examine your child's joints. They will check for signs of:
- Decreased range of motion
- Muscle loss (atrophy) in the muscles near the affected joints
Tests on blood, joints, and tissue fluids can help to rule out other conditions that might cause similar symptoms. These tests may also be used to classify the type of juvenile arthritis.
X-rays provide clear images of dense structures like bone. Your child's doctor may order them to look for injuries to bone or for any unusual development of bone.
Ultrasounds are often obtained to look at the joint. These tests are helpful in determining how much inflammation is present.
Magnetic Resonance Imaging (MRI) Scans
Your child's doctor may order an MRI to look for inflammation in joints or around tendons. An MRI is most often the best way to determine the degree of inflammation, and it can also check for structural changes and injuries.
If your child is young, the doctor may decide that your child needs medicine (sedation) to help them be still for this test.
A child with juvenile arthritis will need treatment from a pediatric rheumatologist. This doctor specializes in helping children with arthritis and related conditions.
Treatment of juvenile arthritis is designed to:
- Reduce swelling
- Maintain full movement of affected joints
- Relieve pain
- Maintain normal growth of the joint
Medications. The most important part of any treatment plan for juvenile arthritis is medication. Your child may need certain medications for several years until the juvenile arthritis is no longer active. Your child's doctor will determine if it is safe to discontinue the medications after joint pain, swelling, and warmth disappear.
- Nonsteroidal anti-inflammatory drugs (NSAIDs)are often the first type of medication recommended. Common examples include ibuprofen and naproxen. NSAIDs are used primarily to reduce inflammation and relieve pain and stiffness; they will help calm down the disease.
- Disease-modifying anti-rheumatic drugs (DMARDs) are the next step if NSAIDs do not relieve symptoms. DMARDs slow or stop progression of juvenile arthritis, but may take weeks or months to relieve symptoms. The most commonly used drug is methotrexate. Your child's doctor may want your child to take DMARDs along with NSAIDs.
- Biologic agents are a class of drugs that also slow or stop the progression of the disease. These medications are typically used if DMARDs are insufficient, but they are sometimes used as iniital treatment if the disease is severe.
- Corticosteroids are stronger medications that may be used in treating severe juvenile arthritis quickly. They can be given several ways, including by mouth (orally), injected into a vein (intravenously), or injected directly into a joint. However, corticosteroids can interfere with a child's growth, and cause weight gain, weakening of the bones, and increased susceptibility to infections. It is, therefore, important to follow the doctor's instructions exactly when taking corticosteroids.
Additional options. In addition to medications, warm baths may help soothe sore joints.
Surgery is rarely needed in treating juvenile arthritis. In very severe forms of juvenile arthritis or with very severe complications, surgery may be necessary to improve the position of the joint. An example of this might be when a joint has become deformed.
Joint replacement — frequently used to treat adults with arthritis — has almost no place in treating children. In addition, adequate treatment of juvenile arthritis will protect the joint and prevent long-term damage that may ultimately require joint replacement.
Living With Juvenile Arthritis
There are many treatment options for juvenile arthritis. The primary goal of all treatment options is to bring about remission of the arthritis. Remission means the child should not have any swelling or inflammation detected by exam or imaging.
Treatment also focuses on preserving children's quality of life by making it possible for them to participate in play, sports, school, and social activities.
In addition to treatment options, school administrators, social workers, and teachers can be important resources. They may be able to develop helpful lesson plans that teach classmates about juvenile arthritis.
With treatment, children should be expected to be able to attend school and have exellent long-term outcomes. Although pain sometimes limits sports and physical activity, children with juvenile arthritis can often fully participate when symptoms are under control.
AAOS does not endorse any treatments, procedures, products, or physicians referenced herein. This information is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopaedic advice or assistance should consult his or her orthopaedic surgeon, or locate one in your area through the AAOS Find an Orthopaedist program on this website.