The Phage in your arm has gotten worse. Hack it to regain control of your hand.
"There are three nerve signals that need to be relayed: muscle control (M) which runs from your central nervous system (CNS) to your hand (HND), and heat (H) and pressure (P), which run the other direction. For each signal, read a value from the input nerve and relay it to the output nerve. Repeat ad infinitum. It is not necessary to leave no trace."