He had a wet dream and was unable to do ghusl, so he did wudoo’ and prayed
Question

                I am a disabled man who is wheelchair bound, Alhamdulillah. I had wet dream before Fajr in some night. Due to the weakness of my body I could not make ghusl, nor could I change my clothes except in the day. I did not want to miss Fajr prayer that day so I just made wudu’ and prayed. Is this permissible or not? What shall I do if it was not permissible? .
Praise be to Allah.
    Firstly: 

    If a person becomes junub as the result of a wet dream or 
    intercourse, then he must do ghusl, because Allaah says (interpretation of 
    the meaning): 

    “O you who believe! Approach not As‑Salaah (the prayer) 
    when you are in a drunken state until you know (the meaning) of what you 
    utter, nor when you are in a state of Janaaba (i.e. in a state of sexual 
    impurity and have not yet taken a bath), except when travelling on the road 
    (without enough water, or just passing through a mosque), till you wash your 
    whole body”

    [al-Nisa’ 4:43]

    If he cannot do ghusl because there is no water available, or 
    because he is unable to use it, then he may do tayammum and prayer, because 
    Allaah says (interpretation of the meaning): 

    “But if you are ill or on a journey, or any of you comes 
    after answering the call of nature, or you have been in contact with women 
    (i.e. sexual intercourse), and you find no water, then perform Tayammum with 
    clean earth and rub therewith your faces and hands. Allaah does not want to 
    place you in difficulty, but He wants to purify you, and to complete His 
    Favour to you that you may be thankful”

    [al-Maa'idah 5:6]

    Similarly, if a person has a wet dream and is afraid that he 
    will become sick if he uses cold water, and he cannot find anything to heat 
    it with, or the water is far away from him and he cannot reach it, and he 
    cannot find anyone to bring it to him, then he may do tayammum and pray. 

    Ibn Qudaamah (may Allaah have mercy on him) said in 
    al-Mughni (1/151): If a person is sick and cannot move, and he cannot 
    find anyone to bring water to him, then he is like one who has no water, 
    because he has no way to get the water. 

    If he has someone who can bring the water to him before the 
    time for prayer ends, then he is like one who has water. 

    If he is afraid that the time for prayer will end before the 
    water can be brought to him, then Ibn Abi Moosa said: He can do tayammum, 
    and he does not have to repeat the prayer. This is the view of al-Hasan. End 
    quote.  

    As for wudoo’, it cannot take the place of ghusl. 

    What you should have done, if you could not find anyone to 
    help you to do ghusl, was to wash whatever you could of your body, such as 
    the head, face, hands and feet, then do tayammum, and pray with this 
    tayammum. 

    For more information please see the answer to question no.
    71202. 

    Based on this, you have to repeat that prayer. 

    Secondly: 

    Maniy is taahir (pure) according to the more correct of the 
    two scholarly opinions, so you do not have to wash or change your clothes. 
    See question no. 2458. 

    We ask Allaah to give you well being in your religious and 
    worldly affairs. 

    And Allaah knows best.