I say, and with God's help: If someone is unable to perform ablution due to surgery on their hand, they may seek assistance from another person to perform it for them. If they do not seek assistance and instead perform dry ablution (tayammum), it is permissible; because, according to Abu Hanifa, a person is not considered capable based on the ability of others. A person is considered capable if they are in a situation where they can perform the action whenever they wish, and this is not achieved through the ability of others. According to the other scholars, capability is established through the means of others; because their means become like their own through assistance. Refer to: Ghunya al-Mustamli 1: 119-120, and Sharh al-Waqaya p.119, and God knows best.