It really depends on the fracture
It was a transverse lower pole fracture. Basically the bottom 1/3 of my kneecap broke off the from the top 2/3 (and the top 2/3 ended up 2cm north of where it should have been!). They didn't need any wires or screws to put it back together, although they had to suture the patella tendon back together. The surgeon thought the patella tendon was probably a bigger issue than the fracture itself, and he was optimistic that given the right rehab it would be back to normal.