Ranking drop for some KW after rectify some broken link

Hi guys,

I have a problem with one of my client site.

As always, as the first thing, I checked the site and I found some broken link in the footer and one in the banner in the homepage. They were links to some category pages but the URLs were wrong . I corrected them, but now all keywords related to those pages are dropped significantly in the serp position. I changed them one week ago.

What do you think? Is it possibile that rectify those broken links has caused the Keyword to lose positions? Have you ever experienced something like this?

Thanks!

P.S.

Sorry for my poor english.