Well ,I have been squatting for over 20 years and I have taught many ladies to squat properly...In my opinion the female knee is stronger than the male knee and not weaker. Men have way more knee problems due to the types of sports they often play.
I have never seen anyone injure a knee from deep squatting WITHOUT a bounce. People get in the rack and start to squat not knowing shit. Most people will either do a half squat, which does dick, unless you have a huge amount of weight on your back and know what the hell you are doing, or they go deep and bounce at the bottom while leaning too far forward!
Generally speaking Men have long torso's and short legs and women are the other way around. Long legs and short torso = leaning forward more in the squat and that = back strain and NOT knee stain. Going very low in the squat, and I am talking about lower than tops of thighs parallel to ground, can be tough on the lower back for all but the very best of squatters. I actually do not recommend this for most people. That said....most people do not go deep enough in the squat. Top of the thighs parallel to the ground is pretty deep.
A wide stance does help if you have longish legs for sure, but then again we are talking about lower back and not the knees.
I have seen MANY people injure their knees doing hack squats( which are FAR inferior to squats) and regular squats with the heels elevated. If you can't stay upright enough flat footed then I think it is better NOT to squat at all. Good substitutions would be the "Tru Squat" Machine, Hammer leg press, and SOME other leg press machines that are easy on the low back.
It is extremely important that one goes fairly deep with all leg press machines too or little development will result.
Forget about the Lunges ladies....the regular back squat will do FAR more for the but, hams and quads, not to mention the adductors and abductors, lower back and abbs. If you just want tone then do high reps and not to failure.
By the way the French pro cycling team, and many other cyclists, do squats to strengthen the KNEE, and not just the bulk of the thigh.
