This is an uncommon injection. This patient had MRI proof of lunocapitate chondromalacia, and very specific pain with palpation at the lunocapitate joint.

These videos are from the same case, but the video recording got cut off. Video 1 shows the needle insertion. Video 2 shows more visual of the “waterfall” (p.13) similar to the acromioclavicular joint injection, as discussed on page 13 and others.

If you see a bubble forming instead of a waterfall, the needle is not deep enough. Get inside the joint. My technique is to go deep enough to touch down on the lunate bone and back up off of the cartilage.

Aim twice, shoot once. (p.5) Watch out for the dorsal carpal branches of the radial and ulnar arteries, which anastomoses with each other around this region. Can you see it in these videos?

Note: the radiolunate joint is hidden from view due to the angle.