Skip to content

    Children's Health

    Font Size
    A
    A
    A

    What Is Benign Hypermobility Joint Syndrome?

    Benign hypermobility joint syndrome (BHJS) means your joints are “looser” than normal. It’s a common joint or muscle problem in children and young adults.

    The condition can cause pain or discomfort after exercise. It’s not part of any disease.

    Recommended Related to Children

    Helping Your Child Use a Nebulizer

    Sometimes children’s allergy symptoms don’t stop with a stuffy nose and watery eyes. If your child has allergic asthma, the most common form of asthma, exposure to allergens like pollen and mold can cause breathing passages to become swollen and inflamed. Childhood allergies that trigger asthma can lead to wheezing, shortness of breath, and difficulty breathing. When that happens, your child’s doctor may prescribe the use of a breathing machine called a nebulizer. The following Q & A will help...

    Read the Helping Your Child Use a Nebulizer article > >

    Symptoms

    Children or young adults with hypermobility usually have joint pain.

    The pain is more common in the legs, such as the calf or thigh muscles. It most often involves large joints such as the knees or elbows. But it can involve any joint.

    Some people also have mild swelling in the affected joints, especially during the late afternoon, at night, or after exercise or activity. That swelling may come and go within hours.

    Who Gets It?

    Girls’ joints tend to be more mobile (looser) than those in boys of the same age. Younger children tend to report more pain. Teens may have fewer symptoms because their muscles and joints become tighter and stronger as they get older.

    BHJS seems to happen more often in Asian-American children than in Caucasian children, and it is least common in African-American children. The reasons for that aren’t clear.

    When large groups of schoolchildren are tested, as many as 40% have the syndrome. About 10% of these children have hypermobility that can lead to pain after activities or at night. No one knows why some children feel that discomfort, while others with equally loose joints don’t have pain or swelling.

    Loose joints often run in families.

    Diagnosis

    Simple tests show whether a child has a greater range of motion in their joints than normal. Doctors use several specific mobility tests, including:

    • The wrist and thumb can be moved downward so the thumb touches the forearm.
    • The little fingers can be extended back beyond 90 degrees.
    • When standing, the knees are abnormally bowed backward when viewed from the side.
    • When fully extended, the arms bend further than normal (beyond straight).
    • When bending at the waist, with the knees straight, the child or adult can put their palms flat on the floor.

    Since the symptoms of hypermobility can sometimes mimic arthritis, you may need to get lab tests to make sure your child doesn’t have a more serious disorder (such as juvenile arthritis or other inflammatory conditions). In rare cases, you may need to get X-rays.

    Today on WebMD

    child with red rash on cheeks
    What’s that rash?
    plate of fruit and veggies
    How healthy is your child’s diet?
     
    smiling baby
    Treating diarrhea, fever and more.
    Middle school band practice
    Understanding your child’s changing body.
     

    worried kid
    fitArticle
    jennifer aniston
    Slideshow
     
    Measles virus
    Article
    sick child
    Slideshow
     

    babyapp
    New
    Child with adhd
    Slideshow
     
    rl with friends
    fitSlideshow
    Child Coughing or Sneezing into Elbow
    Article