Biradial clamp

A biradial clamp was a piece of Borg technology used in the extremities of Borg drones.

In 2378, Seven of Nine's biradial clamp was out of alignment by 0.3 microns causing shoulder pain, a problem easy to fix for The Doctor. Seven wanted to remove the clamp, but this would have prevented her from using the arm. 

Later that year, Two of Three, one of the characters in the Tom Paris-rewritten version of Photons Be Free, suffered from the same misalignment, which The Doctor "cured" by giving her a Klingon aphrodisiac.