2003 Dodge Caravan CV joints

Shakes or Wobbles problem
2003 Dodge Caravan 6 cyl Automatic 90,000 miles

I have noticed that when applying the brakes, my front end shakes, but I thought I needed an alignment and tires rotated. I was told that the cv joints need to be replaced. Also, my mechanic said he heard knocking which is what brought him to the conclusion of the cv joints. Any relation between the two?