No knee surgery puts you in a wheelchair for recovery, unless it's an amputation, once you're in the vehicle on the way home to recover from it. You are given crutches to walk with a normal gait while using your upper body to support your mass moving your center of gravity over the injured joint during movement. Even going up stairs is, slowly, possible as your good leg takes the first step up repeatedly until you get to the top of the set and the crutches are used to elevate your injured leg after it so your weight isn't supported by the recovering joint. If you have surgery on both knees during the same procedure, you would refer to the time you 'had surgery on both knees.'
John's lies are growing less passable by the day than he is at presenting himself as a female.