Comminuted fracture: When the kneecap breaks into multiple displaced pieces, surgeons take out fragments much too modest to fix and reconnect remaining parts with wires and screws. Extreme situations could involve full patella removing. Some fractured patellas don't knit alongside one another appropriately when healing. People might have additional surgery https://www.theorthopaedicandpainpractice.com/what-are-patella-fractures/