When placing three or more pin holes during external fixation, they should be arranged at different levels to maximize mechanical stability of the fixation frame. Placing pins in a single plane reduces the construct's resistance to rotational forces and may lead to pin loosening or failure. Staggering pins improves load distribution across the bone segments and enhances overall fixation rigidity. This technique also helps to avoid weakening the bone by concentrating holes in one area. Proper pin placement is critical for maintaining fracture alignment and promoting healing.

Reference: Rockwood and Green's Fractures in Adults, 8th Edition.