You have told that the knee cap is shattered - for which Patellectomy followed Unicondylar Knee Arthroplasty
(UKA) - Minimally Invasive fixed-bearing UKA gives better results.
You have not mentioned about associated fractured of thigh and leg bones - amputation
and fixing the thigh and leg bone with a rod - I am not able to understand by your question.
You must have entered all the fracturs due to injury