Prayer of Those Having Legal Excuses:

They are the sick, the traveler and those who fear they cannot establish prayer as completely as those without excuses.

The prayer performed by the sick:

Muslim patient must perform prayer standing if he can. If he is unable to stand, then it is permissible for him to sit in prayer. If he is unable to sit, then it is permissible for him to lie on his side facing the Qiblah. It is desirable for him in this case to lie on his right side except if the left one is easier. If there is no one to help him face the Qiblah, he cannot face the Qiblah himself or he finds real difficulty in this, then it is permissible for him to perform prayer facing whatever direction he can face. 

If a Muslim patient cannot lie on his side in prayer, it is permissible for him to lie on his back, making his legs face the Qiblah if possible.

If a Muslim patient sits in prayer or if he lies on his side or back and cannot prostrate, then it is sufficient for him to beckon bowing and prostration with his head, making his head a bit lower to beckon prostration than in bowing. If a Muslim patient sits in prayer and can prostrate, it is obligatory for him to prostrate and it is not sufficient then to beckon prostration with head.

If Muslim patient is unable to beckon with his head, he can intend performing the acts of the prayer in his heart and move his tongue with its words. If he is unable to do even so, he can intend having its words in his heart.