where does "pierce" come from?

I'm writing a (very) brief study of Psalm 22. Most English translations render Psa 22.16 somewhat along the lines of the NASB, which reads:

For dogs have surrounded me; A band of evildoers has encompassed me; They pierced my hands and my feet.

The third phrase of this verse—the one that, for obvious reasons, is most significant for Christian readings of this passage—differs significantly from the text published in the BHS:

כי סבבוני כלבים עדת מרעים הקיפוני דארי ידי ורגלי

kî sĕḇāḇûnî kĕlāḇîm ‘ăḏaṯ mĕrē‘îm hiqqîpûnî kā’ărî yāḏay wĕraglāy

For dogs have encircled me; a congregation of the wicked surrounded me. As the lion my hands and my feet.

The Septuagint is similar, except [*sigh*] for the final phrase:

ὅτι ἐκύκλωσάν με κύνες πολλοἰ συναγωγὴ πονηρευομένων περιέσχον με ὤρυξαν χεῖράς μου καὶ πόδας

hoti ekyklōsan me kynes polloi synagōgē ponēreuomenōn perieschon me ōryxan cheiras mou kai podas

For many dogs have encircled me; a gathering of evildoers has surrounded me; they have dug out my hands and feet.

Brenton translates ὤρυξαν pierced, so I did a (very) little bit of work among the lexica. BDAG offers three general definitions, all of which are related to digging (§5393). Louw-Nida is similar (§19.55), as is Liddell-Scott-Jones (§31131).

Clearly, the English translations (NASB, NLT, NIV, KJV; but not NRSV, NET) exhibit a preference for "pierce" at Psa 22.16, including Brenton's translation of the LXX. Does anyone know where this preference comes from? Granted that the BHS reading is incomprehensible and the LXX isn't obviously related to a Hebrew Vorlage, this verse is certainly perplexing. But given the theological freight that the phrase "they pierced my hands and feet" bears, especially in the very psalm Jesus is said to have quoted from the cross, can anyone provide any rational justification for this translation?