Is prostration waived for someone who cannot bend their left leg after surgery, but can prostrate with only their head and hands while sitting cross-legged?

Prostration (sujood) is one of the pillars of prayer (salaat) and is not waived except in case of inability to perform it. The majority of scholars hold that it is obligatory to prostrate on the forehead, even if not on the other prostrating limbs. If the worshipper is able to prostrate on the forehead and hands, he should only prostrate on them. If he is unable to prostrate on some limbs, he should prostrate on the remaining ones and bring the ailing limb as close to the ground as possible.