Originally Posted by carleton

Actually, doing freeweight squats will better train the stabilizing muscles and tendons.

This guy squats over 1,000lbs "raw" using only neoprene sleeves on his knees to keep them warm. During an interview he says that he's never had knee issues.

https://www.instagram.com/optimusprime_334/

I know he's an abnormal human. But, I'm trying to dispel the common myth that squats cause knee issues. If anything, the hack squat machines select-a-weight machines all run on a track. The athlete must make sure his/her feet are in the right spot in relation to the upper body, otherwise they will cause abnormal loading on the knees. With free weight squats, the upper body is free to adjust as it's not locked into place.

Proper squatting does not cause knee problems. I would suggest focusing on squat technique as you start progressing through your transition back into lifting as opposed to getting strong on the machines then switching over to free weight squats then finding that one small untrained muscle the hard way.