I am only 30 but I've torn my rotator cuff and never had surgery. Took a few months for less pain. I have full range of motion. Took. Few months.

I tore my ACL in my knee that I did have surgery for. Key to all of these joint injuries is PT. gotta work the scar tissue so it doesn't lock the joint. For the knee to help straighten lay on the bed stomach down with ur legs over the edge above the knee. Gravity will help straighten. It will hurt and don't do it very long at first. Pain bad, uncomfortable is ok. Uncomfortable eventually gets better. Really should go to ortho dr or PT. they can help u a lot better. Knee was one week straight leg brace then had to bend 90 degrees and start getting rid of the scar tissue. For torn meniscus it's I believe 1 month to 5 weeks straight leg but that's after surgery. Meniscus isn't invasive they go arthroscopy and generally just scrape it out. Still get a doctor to check on them and give realistic info to u specifically for ur circumstances.