Is it permissible for a woman who has had her leg amputated to pray while sitting, given her ability to stand with a prosthetic limb, in order to avoid the excessive movements resulting from its removal when rising from prostration?

The necessary movement to wear a prosthesis does not invalidate the prayer, even if it is extensive, because there is a need for it to correct the prayer. If standing in prayer causes great difficulty, it is permissible to pray while sitting. Standing is an obligatory pillar in congregational prayer for those who are able, whereas one who sits in a supererogatory prayer receives half the reward of one who stands.