Can someone with a double below the knee amputation walk again?

Yes: This takes a great deal of rehabilitation. A lot depends on the preoperative cardiac and pulmonary function.

Yes but hard : This really depends on the age of the patient and cause of amputation . Young patients with traumatic amputation have better chance, but older patients with gangrene have almost no chance secondary to the large amount of energy to walk which may go above 200% of normal energy needed to walk.

Yes!: Unless the person is in really poor health most people with bilateral below the knee amputations are able to walk. Believe it or not it is harder to walk with one above the knee amputation than with two below the knee amputations.