They're so easy to detect today though with simple X-Rays that I really doubt a slipped disc is actually the cause here. At least I'd like to believe that. But the on-and-off again nature of it seems to indicate that it could be what is going on. It could be a minor herniation(s) which would allow him to play through the pain most days but he would need a rest and some NSAID's regularly with intermittent steroid treatments to keep the pain manageable. You only really need to start sweating nerve damage if you're talking about a serious or major herniation.
Yeah, if it was a herniated disc they would know immediately. But then, herniated discs are often just reported as "back problems".
I played rugby for a few months under what was categorised as a "severe" herniation. My MRI showed that the nerve canal was over 80% blocked by the herniation.
I had a fairly typical L5 S1 herniation. After the initial few days (from which I could barely walk), the symptons lessened with anti-inflammatories. My leg and buttocks were always very tight, so before training and game I got a rub down from the physio. Core strength exercises and stretches also helped, but my herination did not go away - in fact, the symptons became a bit intermittent, some days were fine (although my leg, buttocks and lower back were always tight) then other days were painful and hard to walk.
Despite this, playing was fine. A rub down from the physio would loosen my leg, buttocks and lower back enough to play. A few hours later I would tighten back up.
FYI, the physio basically diagnosed me stright away. I had an X-ray to confirm it, though. Only after it didn't go away for the couple months did I see the sports doctor, get the MRI, visit the surgeon and then finally opt for the surgery.
Pro players also play on with severe herniations before having an op from my understanding. For example, Pat McCutcheon had the same problem a couple years ago and played a couple months on it before opting for the surgery. FYI, Cutch at the time was reported as having "back problems". It's a "common" injury and surgery for sports players.