Definition and Overview
A paediatric joint injection is a medical procedure performed to diagnose and/or treat a condition known as juvenile idiopathic arthritis (JIA).
JIA is a paediatric inflammatory disease that affects the joints. It usually begins around 16 years old and is expected to last for at least six weeks. It is the most popular kind of arthritis and affects at least 300,000 young people aged 21 years and below each year.
JIA has several subsets. These include:
- Juvenile dermatomyositis - characterized by skin rashes on the knuckles and muscle weakness
- Juvenile lupus - a kind of autoimmune disease wherein the immune system attacks the tissues of the body
- Kawasaki disease – characterized by glandular swelling and may lead to complications of the heart
- Juvenile scleroderma - characterized by the tightening of the skin
For many years, JIA, which was called juvenile rheumatoid arthritis (JRA) in the past, has always been considered to be an autoimmune disease. However, the Arthritis Foundation is now looking into the possibility that it could be an auto-inflammatory condition.
To understand the difference, autoimmune diseases develop when the immune system fails to distinguish between foreign invaders and healthy tissues. Meanwhile, auto-inflammatory refers to the innate system, which develops as early as birth. It uses neutrophils and monocytes, which job is to remove substances that can be harmful in the body. When the innate system becomes faulty, it leads to the inflammation of the joints.
Who Should Undergo and Expected Results
Paediatric joint injection may be recommended to:
- Children with a family history of JIA– Some studies, including those performed on twins, suggest that the risk of developing JIA is high among those who have family members diagnosed with the condition.
- Those showing certain signs and symptoms – Signs and symptoms can vary depending on the subset and the actual experience of the child. However, they typically involve joint pain and swelling, stiffness of the joints particularly in the morning, irritability, difficulty in walking, muscle pain, rashes and fever. A distinct characteristic of JIA is that its symptoms can last for 6 weeks.
- Children whose joint pain may be caused by a bacterial infection
- Those with JIA whose previous treatment did not work – A corticosteroid injection is administered as the last resort to treat the condition.
How Does the Procedure Work?
Paediatric joint injection can be performed as a diagnostic or therapeutic procedure.
When performed to diagnose JIA, the procedure is also called arthrocentesis. It starts by administering local anesthetic to the target site followed by an antiseptic. A syringe with a needle is then slowly inserted into the target area to draw joint fluid, which is then analyzed in a laboratory.
There are cases wherein the child may have to be sedated prior to the procedure, especially if he’s young or anxious. In this case, the child, together with his parents, needs to discuss the sedation process with an anesthesiologist. Children should fast prior to the drawing of fluid—that is, they can eat a full meal at least 8 hours before the sedation and no food or water within two hours before sedation. After the procedure, the patient will be provided antibiotics to prevent infections from developing.
The paediatric joint injection may also be performed to provide treatment for JIA. A syringe with needle is used to apply corticosteroids such as methyl-prednisolone, triamcinolone acetonide, or triamcinolone hexacetonide. All of them are administered one to three times per year or on as-needed basis particularly for mild cases.
Possible Risks and Complications
Corticosteroids are stronger than other types of arthritis drugs, and since they are injected directly into the joint, the effects are immediate. Symptoms are expected to subside within a few days after the procedure and the effect can last for a long time. Although corticosteroids have side effects, which explain why they are applied only a few times per year, the risks are still considered very low.
Nevertheless, doctors, parents and children need to watch out for infection accompanied by fever, swelling on the injected area, and redness. Patients who exhibit these signs within 24 to 48 hours after the injection must see their doctor right away.
The patient may also experience mild to severe pain. In a 2010 research participated by more than 160 doctors who worked with 33 JIA children with an average age of 8, around 78% experienced mild to zero pain while 4% complained of severe pain.
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