They did set up a study, informally, like you would do in most sciences for an exploratory experiment. But it was shut down by the FDA. And to comply with FDA

They did set up a study, informally, like you would do in most sciences for an exploratory experiment. But it was shut down by the FDA. And to comply with FDA rules (which are designed specifically for drug testing and exploring new surgical processes) it would have taken six years and been too expensive for their budget. So they went to the UK and completed the study in six months for free. The US lost out on that.