Is it abnormal to be “double-jointed?”
The technical medical term for “double-jointedness” is joint hypermobility. Mobility of the joints is a trait that can differ among individuals based on many factors including genetics, age, sex, race, and physical conditioning. Joint hypermobility may offer a physical advantage in athletics, like gymnastics or throwing a baseball. However, children and adolescents with joint hypermobility do have a mildly increased risk (as compared to the general population) of sustaining a sports injury or developing activity-induced joint pain.
I think my child is “double-jointed.” How can a physician assess this?
A physician can perform a physical examination and measure something called a Beighton score. This involves hyperextending a child’s fingers, elbows, knees, and having them bend down to touch the floor. The Beighton score will be a number that can range from the lowest score of 0 to a maximum score of 9, but experts disagree on what constitutes an “abnormal score.” Generally, if a child has a score above 5, that means the child is pretty flexible, but does not mean a genetic disease is present. In fact, usually it means that a child is simply more flexible than other children and has no additional meaning beyond that.
If my child has joint hypermobility on physical examination, does that mean he/she has Ehlers-Danlos syndrome (EDS)?
Many children who have joint hypermobility show no other symptoms. If your child is otherwise healthy, with normal growth and development, and does not have any symptoms of pain or frequent joint dislocations, he or she is unlikely to have a medically significant genetic disorder.
What are the types of EDS?
There are many different subtypes of EDS. The most common subtype is hypermobile EDS (hEDS), and that is what most people are referring to when they talk about “EDS” in the general sense.
Hypermobile EDS is diagnosed by features based upon a clinic visit. There is no genetic test to confirm the diagnosis.
In order to be diagnosed with hEDS, a child must have a positive Beighton score and two out of three of the following: examination features of a connective tissue disorder, a positive family history of hEDS, and/or skeletal complications including chronic widespread pain or recurrent joint dislocations. A child must also not have other features that could indicate a separate genetic disorder for which genetic testing is available.
Diagnostic criteria became more strict in 2017, so it is possible that a child will be somewhat flexible and have intermittent complaints of joint pain and not meet criteria for the diagnosis of hEDS. Younger children will often have an “elevated” Beighton score, so it is often not possible to determine that joint hypermobility is abnormal until a child is 8 to 10 years old.
Vascular EDS (vEDS) is a completely different condition than hEDS. There typically is no joint hypermobility and/or pain. It typically presents in adulthood with significant bleeding or an aneurysm (weakness of large blood vessels). Although individuals with vEDS have hypermobility of their fingers and toes, they often do not have hypermobility of other joints. The likelihood that a child with features of hEDS actually has vEDS is incredibly low. vEDS is typically inherited from an affected parent. In this scenario, an affected parent would most likely have a major blood vessel or organ complication prior to any complications in their children, thus alerting the family to the risk and allowing for all at-risk family members, including the child, to be diagnosed.
Does my child need to be evaluated by a medical geneticist?
This is up to the child’s physician. An appointment with a geneticist is typically an information-only visit, therefore it is most likely to be helpful in the case where the family feels like they need some questions answered. The medical genetics evaluation will likely consist of a history and physical examination only. Unless other concerning features are identified, it is unlikely that genetic testing will be performed. Also, medical geneticists do not treat chronic pain in patients with hEDS, so the geneticist will not be making adjustments to the child’s pain management regimen at the visit.
I have read a lot of information online about Ehlers-Danlos syndrome and have a concern/concerns about my child or other family members.
In this case, it is probably best that you arrange for an appointment with a physician knowledgeable about EDS. This may be a medical geneticist but, depending on the concern, may be a different type of specialist. For more information or to complete our hypermobility questionnaire, click here.