You can model a leg/arm/head/whatever, add scenery to the bipd with that model... And move on from there some how?
I would assume you'd then make all the weapons (or chainsaw i assume

) spawn the ligament, but you'd have to sync it so the leg/arm would come off the main bipid, and stay off until respawn, then it would reset, and you'd somehow have to make it so depending on where you attacked the bipid it would loose certain limbs... I would suggest looking into the features of the flood human bipid... and make the legs/arms actually come off.