EE was replacing a brake shoe on locomotive 3804 at South Fort Meade on the right side of journal box 2, when the shoe slipped off of the brake shoe holder pinching their right pinky between the brake rigging and a 25lb brake shoe at a drop of 3"" to 4"". Xray completed 4/18/22 that showed, nondisplaced fracture of the right Pinky.