Q: My dad pees on the toilet floor & he gets filth in his underwear etc. I wash his underwear, pants, carpet, floor-towels & private-part towels by hand before putting them in the washer. My hands hurt from squeezing & im sick of it since the najas returns so quickly anyway. Is there a rukhsa for me?
A: Yes. If wringing the soiled clothing becomes too difficult, you can pound, agitate, or press it (outside of the water source) in a manner which removes most of the water after each of the seven washes.
May Allah reward you for patiently serving your father.
Source: Sharh al-Muntaha