When you hit 0 hp in Moldvay's Basic D&D you die. This works, but by default the game system does not really have ways to seperate players from their body parts...
When a player character hits 0 HP or fewer, roll on this table. 1d6 for location, and 1d6 for death and mayhem to share. Also you're out of the fight.
| Location | Maims on | Kills on |
|---|---|---|
| 1-2 (Left & right arms) | 5+ | 6 |
| 3-4 (Left & right leg) | 4+ | 5+ |
| 5 (Torso) | -- | 4+ |
| 6 (Head) | 2+* | 3+ |
| No maims or kills: describe yourself a badass scar and write it on your character sheet. |
*-A head maiming means losing an eye or other facial feature. This has no mechanical effect unless both eyes are lost.
With one working leg you're slow, with no working legs you can only drag yourself along at a crawl. Crutches fix this, but they each keep a hand full. Peg legs and hook hands are available at the local surgeon barber or carpenter and installation is cheap and discrete.