Amputation was the choice as infection and gangrene would set in. However, anaesthesia is a challenge in this case as the margin of safety is low in such small creatures. A bit more anaesthesia would kill. I gave 2 drops of Zoletil 50 IM and operated fast, within 10 minutes to remove the leg. Details are in the illustration and video.
As at 7 days after surgery, the hamster is OK and active.