Do your knees make cracking or popping sounds? Mine do, plus a little "grinding" sound on the right side sometimes. Many of the crackles are normal and nothing to worry about, according to this article.
It is so common for people over the age of 50 to have knee dysfunction or pain. Knee problems could be due to injury or regular wear-and-tear over decades of activity. This can affect the ACL, the ligament which stabilizes the knee, or the menisci, which are cartilages that act like shock absorbers.
The good news is that the knee is surrounded by connective tissue and muscles. By working on the upper, inner and outer thighs, as well as the hamstrings, calves, and shins, we build support for the knees.
In yoga, in addition to the outer muscles, we also work from the inside out. This is what we mean when I say "imagine hugging the bone", so we can engage the muscles closest to the bone, and work outward.
If you want to practice yoga with me to help you keep your knees and legs strong, I provide many yoga options, including group classes or 1-on-1 sessions via Zoom or in-person, and video recordings.