Shake your tail feather.

Top Line: While consensus contouring guidelines for spine radiosurgery have been at our disposal for years, the sacrum hasn’t garnered much love.

The Study: That could be because only 5% of spine mets wind up there. But it’s worth noting the anatomic and functional distinctions from its superior brethren, namely a lack of intervertebral disc space that not only precludes mobility but may also mean the sacrum lacks analogous barriers to disease spread. Luckily, in 2020, you no longer have to guess if you’re treating the sacrum right. Experts from nine high-volume centers across the US, Canada and South Korea convened to bring us these consensus guidelines on sacral radiosurgery targets. You’ve really just gotta look at the examples, as the CTVs may be more detailed than you think. They also recommend drawing the thecal sac all the way down to the tip of the tailbone to include all nerve rootlets, in addition to drawing the lumbo-sacral nerve roots, to avoid ill-placed hotspots.

TBL: These guidelines can help you draw anatomically-savvy sacral radiosurgery targets. | Dunne, Radiother Oncol 2020