(a) It is narrated from al-Azraq bin Qays: I saw Sayyiduna Ibn Umar (may Allah be pleased with them both): when he stood up from two rak'ahs, he would rise supporting himself on the ground with his hands. I said to his sons and his companions: Perhaps he does this because of old age? They said: No, but this is something that may be done.
(b) We have already mentioned the narration of Nafi' (may Allah have mercy on him) that it is reported from Sayyiduna Ibn Umar (may Allah be pleased with them both) that when he rose from the prostration, he would rise supporting himself on the ground; and al-Hasan al-Basri (may Allah have mercy on him) and many of the Successors (may Allah have mercy on them) used to do the same.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2806