Unless you have Kaiser health plan, in which case the ortho doc doesn't need anyone's permission (but won't do it if you're significantly overweight or out of control diabetic). (Shameless Kaiser ad, I used to work there--thrive and all that.) And if I were an insurance underwriter I would think an ACL repair that allowed an older patient to stay active would pay for itself in the long run--maybe they'll have more sports injuries, but will have less obesity and other complications of a sedentary life--and obesity is a big contributing factor to osteoarthritis which leads to expensive joint replacement.
Had Kaiser when I hurt my leg at Whister. You have to through your primary first to get to Ortho. In my case, I had to have persistent pain for 30 days before primary could get me appointment to Ortho. He could not order MRI as Lachman test was negative (that's where they manipulate the knee to see if ACL damaged). I paid for my own MRI, waited the 30 days and got Ortho appointment. Ortho does standard X-ray. He's looking at X-ray, which really shows noting on tissue damage and I tell him I have MRI CD. He says, Gimme that thing!. Meniscal tear but I'm older and he said that was probably existing. He could order repair but if it was not bothering me, he'd recommend leaving it alone. Good advice which you will hear with ACL tear also.
I like Kaiser but that same algorithm applies to most health insurance. Most are based on Medicare algorithms and issue for older people is proving the need for an ACL repair. "I like to ski" will not work. You need to work with your ortho and create "Limit to ADL (activities of daily living)" parameters. Ortho's will work with you as they make their living doing surgery but over 60 and you have to make a good case for ACL repair. It's not an automatic.