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

Children are usually 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 or 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, dislocated joints, sprains and strains.

Medical conditions associated with hypermobility syndrome include Down syndromeEhlers-Danlos syndrome and Marfan syndrome.