Doctors and safety experts say better awareness is needed about the dangers - especially the risks of putting heavier, older model TV sets on top of dressers and other furniture young children may try to climb on.
Most injuries are in kids under 5; head and neck injuries including concussions are the most common.
"This is a problem that is increasing at an alarming rate," said lead author Dr. Gary Smith, a pediatric emergency specialist and president of the Child Injury Prevention Alliance in Columbus, Ohio.
Smith said it is unclear from the data what type of TV sets are involved in the accidents or whether older, heavier models are the most common culprit.
The study was published online Monday in the journal Pediatrics.
In 2011, 12,300 children nationwide got ER treatment for TV-related injuries, compared with 5,455 in 1990. The injury rate nearly doubled, from 0.85 injuries per 10,000 children aged 17 and younger in 1990 to 1.66 per 10,000 in 2011, the study found.
The researchers examined national ER data on non-fatal television-related injuries to kids from 1990-2011. In many cases, the set had been placed on a dresser and the child used open drawers as stairs to climb up and reach the TV, toppling it.
Over those two decades, 215 children died from these injuries, government data show, and news reports indicate that since January 2012, at least six young children have been killed nationwide by falling TVs.
Scott Wolfson, spokesman for the government's Consumer Product Safety Commission, said as flat screen TVs have become more popular, many families move heavier old TVs to bedrooms, placing them on dressers or other unsteady furniture not designed to hold them.
The commission urges parents to anchor furniture to the wall or floor with brackets or other specially designed tethers. TVs also should be anchored to sturdy surfaces, the commission recommends.