happened to me around 43 yo. Series of nasty pulls rendering me nearly unable to walk for a while. Resulted mainly from lack of use back muscles in my 30s. But it really only takes one year of not exercising back muscles to make them especially susceptible to injury. Sibling had same issue. Went to doc to try to go on disability. Doc said muscles are weak, strengthen them and you'll be fine. Said sibling is not taking docs advise. Guess they really want to go on disability LOL.
For me I corrected the problem and have since made nearly a full recovery. Simply by doing a regiment of lower back strengthening exercises and stretching every day. But very careful, mostly light stretching in the early going. Been doing that for about 3 years now. Another huge benefit has been losing about 50 lbs.