Despite the fact that feodor's hands shake and he has a difficult time walking, positioning, and moving his body to get in and out of chairs, he remains mentally sharp. feodor appears to have:

Feodor’s appears to have a Parkinson's disease. PD is a longstanding worsening disorder of the central nervous system that mostly affects the motor system. The indications commonly come on slowly over time. Early in the disease, the most noticeable are shaking, rigidity, slowness of movement, and difficulty with walking.