How to perform the ritual bath for a person with a head injury

Question:
He also says: If a man is in a state of major ritual impurity and wants to take a ritual bath, but the doctor has prevented him from letting water touch his head because he is ill, what should he do?

Answer:
If he is ill and water would harm his head, he should take a ritual bath over his entire body. When he is finished, he should perform dry ablution with the intention for his head, striking the earth with his hands and wiping his face and palms with the intention for his head. Likewise, if the doctor prevents him from washing one of his hands or one of his feet, he should wash the healthy part and perform dry ablution with the intention for the part that was not washed. This is because dry ablution takes the place of water when one is unable to use water. Allah has made the earth a place of purification and a place of worship . Therefore, the one who cannot wash his head or any of his limbs should wash the rest, then perform dry ablution by striking the earth with his hands once and wiping his face and palms with them, with the intention for the limb that was not washed, whether it is his head or something else. Yes.