Wrist drop
Inability to lift the hand back at the wrist because of radial nerve damage; in rope bondage it is the classic sign of an upper-arm nerve compression.
In Shibari Study’s glossary, wrist drop, also called radial nerve palsy, is difficulty raising the wrist after the radial nerve has been compressed. MedlinePlus lists trouble bending the wrist backward, a weak grip and altered sensation on the back of the hand among the signs of radial nerve damage. In the 2023 Cureus case series by Khodulev and colleagues, people with rope-related radial injuries frequently reported numbness on the back of the wrist and weakness in lifting the wrist and fingers, ranging from complete paralysis to moderate weakness. Most recovered within about a month, one first episode took five months, and the authors judged the outlook generally favorable while warning that injuries can recur. Rope 365 notes that the motor damage behind wrist drop can occur without pain.