"Double-jointed"

Everyone at some point in their childhood knows a kid who is "double jointed". Though many outgrow loose joints, some actually have a condition that can leave them in pain and arthritic later in life.

Hypermobility syndrome is a joint condition that allows movement beyond the normal function of the joint. The connections between bones are usually contained within a network of ligaments and connective tissue that support and control the movement of the bones. When these supporting tissues are “loose”, they allow abnormal movements. This stress can cause pain, irritation, and discomfort.

Signs of hypermobility

Signs of hypermobility include:

• ability to place the palms of the hands on the floor with the knees fully extended
  
• hyperextension of the knee or elbow beyond 10 degrees
• ability to touch the thumb to the forearm

Benign hypermobility syndrome often manifests early in life as “growing pains”, but it is not the same condition and the pain continues into adulthood. The joints may swell when used, such as late afternoon, at night, and after exercise, with resolution in a few hours. The swelling is caused by an accumulation of fluid in the joint capsule due to irritation from the loose connective tissues. Pain is more common in the larger joints and lower extremities. Signs of inflammation (redness and heat) are not common. Partial dislocation may occur as well, with visible movement of the joints.

Who is at risk for hypermobility

Ten to fifteen percent of normal children have hypermobile joints. The condition can run in families when it is caused by a defect in collagen genes. Children are naturally more flexible than adults because their skeletons are still growing. Hypermobility often causes little discomfort until adulthood.

Complications of hypermobile joints

Hypermobility syndrome can also be a feature of Ehlers-Danlos syndrome. This generalized syndrome causes weakness of the connective tissue. It is an inherited defect that also causes elastic skin, easy bruising, and damage to blood vessels. Other chronic medical conditions that can cause hypermobility are Marfan syndrome, Marquio syndrome, and Cleidocranial dysostosis.

Hypermobility can lead to arthritis and an increased risk of sprains and strains. Scoliosis is more common in those with “loose joints”.

Treatment of hypermobility

There is generally no treatment for hypermobile joints. Physical fitness is recommended to strengthen muscles, stabilizing the skeleton. However, exercises should be chosen that prevent stress on the joints or any that are particularly affected by the syndrome. Joint pain can be treated with anti-inflammatories, pain relievers, and arthritis drugs as directed by a doctor. Rheumatologists are often consulted when the syndrome causes other health issues with the joints.