The Circus Maximus known as the National Football League alighted in London for a game between the Dallas Cowboys and the Jacksonville Jaguars. The league’s many fascinations will be on display: its wonderful athleticism, its stupendous television ratings, and its blithe disregard for the safety of its most valuable commodities, the players.

Nearly two weeks ago, a 6-foot-3, 240-pound Redskins linebacker sprinted, spun and drove his knee into the back of Tony Romo, the Cowboys’ quarterback.

That hit caused Romo’s back muscles to yank apart so hard that pieces of two vertebrae chipped and fractured in his lower back. That injury, most typically seen in auto or airplane accidents, did not threaten the stability of Romo’s spine.

It did result in intense pain. And it takes six to eight weeks to begin to heal.

“I’ve had patients on the floor with this,” said the orthopedist John Bendo, a clinical professor at the New York University Langone Hospital for Joint Disease. “Two weeks later? Romo’s still in a lot of pain. A lot. It’s acute.”