I underwent a surgery and the "local inflamou" because the stitches broke out.

I underwent a surgery and it got/has/became swollen because the stitches broke out.

I underwent a surgery and it got/has/became inflamed because the stitches broke out.

I underwent a surgery and it got/has/became inflamed because the stitches broke out.

Notice:

I think inflamed is a more 'medical-jargon' wise and swollen more, say, colloquial.

PP.