Every bone inside Virus' body was currently in its peak condition, meaning it had absorbed a hundred percent of the energy it was supposed to take in. Moreover, the technologically advanced Earth of the future had also invented some methods by utilizing which, one was able to even transmit these energies to the cartilage along with the bones itself!
Actually, the same thing had also taken place when Virus was still at the second level, Altering The Flesh. Because in that particular level, with some minor adjustments, the tendons and ligaments also came to be considered a part of the flesh. Naturally, the veins and arteries, which existed inside the flesh itself, were already considered a part of the flesh in this particular level without any kind of further adjustments necessary.