Hypermobile joints are joints that move beyond the normal range with little effort. Joints most commonly affected are the elbows, wrists, fingers, and knees.

Joint hypermobility; Loose joints; Hypermobility syndrome

Children are often more flexible than adults, but those with hypermobile joints can flex and extend their joints beyond what is considered normal. The movement is done without too much force and without discomfort.

Thick bands of tissue called ligaments help hold joints together and keep them from moving too much or too far. In children with hypermobility syndrome, those ligaments are loose or weak. This may lead to:

• Arthritis, which may develop over time
• Dislocated joints, which is a separation of two bones where they meet at a joint
• Sprains and strains

Children with hypermobile joints also often have flat feet.

Hypermobile joints often occur in otherwise healthy and normal children. This is called benign hypermobility syndrome.

Rare medical conditions associated with hypermobile joints include:

• Cleidocranial dysostosis
• Down syndrome
• Ehlers-Danlos syndrome
• Marfan syndrome
• Morquio syndrome

There is no specific care for this condition. Persons with hypermobile joints have an increased risk for joint dislocation and other problems.

Extra care may be needed to protect the joints. Ask your health care provider for recommendations.

Call your health care provider if:

• A joint suddenly appears misshapen
• An arm or leg suddenly does not move properly
• Pain occurs when moving a joint
• The ability to move a joint suddenly changes or decreases

Hypermobile joints often accompany other symptoms that, taken together, define a specific syndrome or condition. A diagnosis is based on a family history, medical history, and a complete physical exam.

Medical history questions that help document hypermobile joints in detail may include:

• When did you first notice the problem?
• Is it getting worse or more noticeable?
• Are there any other symptoms, such as swelling or redness around the joint?
• Is there any history of joint dislocation, difficulty walking, or difficulty using the arms?

The physical exam will include detailed examination of the muscles and skeleton. The joints may be moved to determine the direction and extent of mobility.

Further tests will depend on what condition is suspected.

Krakow D. Heritable diseases of connective tissue. In: Firestein Gs, Budd RC, Harris ED Jr., et al, eds. Kelley's Textbook of Rheumatology. 8th ed. Philadelphia, Pa: Saunders Elsevier;2008:chap 96.