Being double jointed doesn't mean people have been born with a second set of joints. More accurately the condition is referred to as joint hypermobility or laxity. What this name means is that people can stretch certain joints beyond a normal range of motion, and this condition might result from perfectly ordinary circumstances. Alternately, it can be indicator of presence of serious disease, and may prove medically problematic...
What Makes Some People Double Jointed?
What Makes Some People Double Jointed?
