@tani I have been doing a lot of physical therapy because of recovering from an ankle fracture 2 years ago. The alignment of everything through the pelvis, hips, knees, and ankles is very important. I lost a bit of cartilage in my injury, and my ankle isn't as stable now. If I circle it around, it cracks a lot, and there are slight differences in alignment that cause pain and I can't step on my foot. My PT showed me how to release it when it gets locked up and push it back into better alignment. Some of it could be caused by weakness for not having normal use of muscles during recovery, or that it also is weak enough that it just gets tired and slips a bit.

The muscles can also be too tight around the pelvis, and this happens from sitting too much causing the hip flexors to be too tight. Tightness can pull on everything down the leg and cause uneven pressure on joints. My physical therapist also does myofascial release which can help balance the body and stretch out the places that are overly tight. You may be interested in our discussion on Myofascial Release.

Myofascial Release Therapy (MFR) for treating compression and pain:
https://connect.mayoclinic.org/discussion/myofascial-release-therapy-mfr-for-treating-compression-and-pain/