Inexplicable Glitch - Not "Missing Hands" but "Severed" Hands...

[BarbarossaKain]

I have an issue that has popped up on a new Modlist/Build out I've put together:  I have random NPCs that show up with missing hands.  Well, not missing really... they have no hands/forearms (they are invisible), and, the Wrists guards/Gloves appear sitting on the ground next to them.  The hand items in question look as if you had dropped them from your inventory.  Just sitting there nicely on the ground at the NPC's feet.  

This is an occurrence that happens very infrequently:  Once to a random male Vigilant  on patrol, and once to a Modpocalpyse NPC in the Kyne Temple in "Great Village of Kynesgrove" mod.

I tried disabling the various Armor Mods I had installed to no effect.

The thing is, I don't think it is a Mesh Issue, as I can see the hands - they are just not attached to the NPC's body. 

Might it be due to an Animation Mod?  I have a 1000+ Plug-in list that I am running, so it is hard to even know where to begin the start narrowing the field of investigation.

Any ideas or guidance that anyone might be able to share would be most welcome and appreciated.

 

[scorrp10]

What is most likely happening is mod author mistakenly designated a 'ground mesh' file (how object looks in inventory/dropped into world) instead of a 'skinned'  (designed to be worn) file.  The fix for this might be as simple as a few clicks in BodySlide.

So, how you track this: first, you need to ID the item.  First, be sure to install More Informative Console
When you see an NPC affected by this, you open console, click this NPC, and use command:   showinventory    

It will list the items this NPC has, and it should be fairly obvious  what is their worn hands item.    Obviously, your item name and ID will be different, but look for a line like:
1 - Hide Gloves (1D016526) (100,100.00%) - Worn - Outfit ''

Now that you know the ID of what they are wearing, you can examine the item.   Oh, be sure to note if the NPC is a Khajiit or Argonian, and if they are a male or female.

Using the ID in the parenthesis (leading zeros can be skipped), summon a copy of this item at your feet:   player.placeatme 1D016526
If you now step aside and look down, the item should be there on the ground.    If it is not, likely this piece has been flagged 'non-playable' or was not given a ground mesh.   This is quite rare, but if that happens, then this ID will need to be tracked by external means.    
Open the console and click the item lying on the ground.   On the right side, there should be info about its origin, i.e.:

You can see that this piece is defined in YurianaWench.esp, so this is an item added by a mod.   If it is defined in Skyrim.esm or one of main DLC .esms,  this is a visual replacer item.
Next, look at item info panel in upper left.    You can 'drill down' into a category by mousing over it and pressing Shift.

First, you need to go into "Armor addon".   In second, if there are multiple options, select Khajiit or Argonian if that is NPC's race.   Otherwise, 'Default Race'.  Then, depending on NPC's sex, go 'Model Male' or 'Model Female', and finally - Model Path. (relative to Data\Meshes)
Specifically, the path of model file in this case is Data\Meshes\actors\character\YurianaWench\shitty\hide\gaunt_1.nif

So, once you determine what is the offending item, what plugin is it defined in, and the problematic model file, you can post all that info here.
Also.   If the item is added by a mod, you can go to the mod page, and file a bug with mod author.   
If the item is a replacer:   (i.e. base defined in Dragonborn.esm) - you can try to check which mod is responsible for the offending model file.    

[BarbarossaKain]

@scorrp10 Thank you for the detailed reply!  Next time I come across an afflicted NPC I shall use your recommendation here.  Thank you again.