I and many others have learned that head and neck radiation isn’t over when the treatment is done. The long term damage to the nerves even just small amounts of scatter exposure, down the road damage nerves, and peripheral neuropathy can result. Because all your nerves at the base of the skull end up far away from that location, even tingling or numbness in the legs and feet is possible.
Often these do not manifest till many years after the treatment. There isn’t anything that can be done about this it seems. Keeping the arm, or impacted area, exercised and active will keep the muscles and underlying vascularization healthy which will offset many times this getting any worse. B

Brian, stage 4 oral cancer survivor. OCF Founder and Director. The first responsibility of a leader is to define reality. The last is to say thank you. In between, the leader is a servant.