When I went through my knee surgery, I was using crutches. It did help me a lot in my recovery. But there are other means of alternatives to crutches and wheelchairs. What you can use is knee scooters. It can be three or four-wheeled. Its helpful for people who may had accidents having their leg and arm both getting damaged. For such people crutches are pretty much useless.
It took me some time to learn to walk using crutches when I first started using it. As I have heard knee scooters also has a learning curve to be able to use it properly.