Question
A woman underwent a knee joint replacement surgery, and she is unable to stand for ablution. Is it permissible for her to perform tayammum? And when she enters the restroom, she is unable to clean herself completely from impurity; is her prayer valid if there remains some impurity?
Answer
I say, and with God's success: If she is unable to use water by herself, it is permissible for her to perform tayammum, and her prayer is valid even if there is a small amount of water that is excusable, which is less than a dirham on her clothes, and God knows best.