Injury to the hand is a pretty common motif in heroic legends. One story where it's particularly important is the legend of Perceval and the Holy Grail. The Fisher King is one figure in the story and has a wound to the hand (and in some versions, the 'thigh'
that won't heal. Perceval himself also burns his hand in some versions of the story. The Fisher King can only be healed by the Holy Grail, which is kept in the Grail Castle. Perceval has already encountered the castle once in his youth, where he gained admittance quite easily; when he has to deliberately return to it later, it's much more of an ordeal.
Anakin parallels both the Fisher King and Perceval (who at one point mistakes someone for an angel!), while Luke parallels Perceval. The Death Star, in its two incarnations, parallels the Grail Castle which Perceval visits twice.
Other characters you might know who get their hands or arms wounded include Johnny Tremain, Captain Hook, Thomas Covenant, the hero in 'Desperado', and Frodo Baggins. There are also a lot of stories where the hero or a figure important to the hero receives some other kind of wound (often a burn) or even just emotional harm that just won't heal. Anakin Skywalker eventually gets all three manifestations of this sort of harm: he loses his hand, he gets burned (or so we've heard), and he gets seduced by the Dark Side of the Force.
Some of these connections may sound like a bit of a stretch in the short descriptions I'm giving here. The more you learn about the patterns, though, the more apparent they are in different stories. There's a lot of psychological interpretation that begins with the idea that hands/arms are often phallic symbols. So a wound to the hand is symbollicaly an injury to a character's masculinity. Healing that injury is what drives a lot of heroic tales.
