I say, and with God's success: Wiping over the splint should be done once, on the most tightly bound part of the member, and it is not required to wipe over the splint three times: whether it is bound with a splint or a cloth tied over a wound or fracture, and he is unable to wash the member or wipe it. Refer to: Al-Muhit p. 374, Al-Maraqiy p. 135, Al-Durr Al-Mukhtar 1: 187, Al-Bahr 1: 198, and God knows best.