Changes to Shutdown Syndrome.

Now it only affects limbs.
Icon is changed to deformed to reflect it.
Dead limbs do not cause pain messages.

code/modules/organs/organ_external.dm

@@ -596,7 +596,7 @@
 	return 0
 
 /datum/organ/external/get_icon(gender="")
-	if (status & ORGAN_MUTATED)
+	if (status & ORGAN_MUTATED|ORGAN_DEAD)
 		return new /icon(owner.deform_icon, "[icon_name][gender ? "_[gender]" : ""]")
 	else
 		return new /icon(owner.race_icon, "[icon_name][gender ? "_[gender]" : ""]")

code/modules/organs/pain.dm

@@ -83,7 +83,7 @@ mob/living/carbon/human/proc/handle_pain()
 	for(var/datum/organ/external/E in organs)
 		// amputated limbs don't cause pain
 		if(E.amputated) continue
-
+		if(E.status & ORGAN_DEAD) continue
 		var/dam = E.get_damage()
 		// make the choice of the organ depend on damage,
 		// but also sometimes use one of the less damaged ones

code/modules/virus2/effect.dm

@@ -134,10 +134,13 @@
 	activate(var/mob/living/carbon/mob,var/multiplier)
 		if(istype(mob, /mob/living/carbon/human))
 			var/mob/living/carbon/human/H = mob
-			var/datum/organ/external/E = pick(H.organs)
+			var/organ = pick(list("r_arm","l_arm","r_leg","r_leg"))
+			var/datum/organ/external/E = H.organs_by_name[organ]
 			if (!(E.status & ORGAN_DEAD))
 				E.status |= ORGAN_DEAD
 				H << "<span class='notice'>You can't feel your [E.display_name] anymore...</span>"
+				for (var/datum/organ/external/C in E.children)
+					C.status |= ORGAN_DEAD
 		mob.adjustToxLoss(15*multiplier)
 
 	deactivate(var/mob/living/carbon/mob,var/multiplier)
@@ -145,6 +148,8 @@
 			var/mob/living/carbon/human/H = mob
 			for (var/datum/organ/external/E in H.organs)
 				E.status &= ~ORGAN_DEAD
+				for (var/datum/organ/external/C in E.children)
+					C.status &= ~ORGAN_DEAD
 
 /datum/disease2/effect/immortal
 	name = "Longevity Syndrome"