They look like ordinary sneakers, but when the user shifts his weight in roller shoes, wheels pop out of the heel, resulting in a fun and sometimes dangerous ride.    

"They typically just fall backwards, their feet come right out from under them," said Dr. Robert Bruce of the Emory School of Medicine.    

Pediatric Orthopedist Robert Bruce has seen up to 20 young patients in the past year with roller shoe injuries.
   
"Fractures, broken bones, more frequently elbows than wrists, but wrists and elbows mostly," said Dr. Bruce.
   
The Consumer Product Safety Commission reports 1,600 emergency room visits in 2006 because of roller shoes, compared with 480,000 trips because of bicycle injuries.   

Heelys, the most popular brand of roller shoes, includes safety information in the packaging and says quote: "We continue to recommend the use of helmets, wrist guards, elbow pads and knee pads."   

Dr. Bruce says his injured patients admitted they weren't wearing any protective gear.    

"In an ideal world, they would have head protection because a head injury does not recover, does not heal, they would have maybe wrist guards or elbow pads," said Dr. Bruce.     

He claims many injuries occur when the roller shoes are new and kids are just learning to get their balance.