Oxford admissions mitigating circumstances

How seriously does Oxford take mitigating circumstances?
I had to undergo major surgery due to a life threatening illness, and as a result I only achieved the bare minimum grades to meet the entry requirements for the course I am applying to (AAA- law).
The mitigating circumstances are in my reference, does anyone have any experience with applying with mitigating circumstances who can tell me whether it had any impact on the application?

Hey, sorry to hear about your circumstances. I also suffered from health issues that meant I missed more than half of sixth form and home-schooled most of it. My circumstances were explained in my application but it made little difference. Having mitigating circumstances may mean they look more generously towards you, but remember it is only context that enhances your existing achievement; they are by no means a free ticket halfway there. They take students who can perform, and are more likely to admit those who have proved themselves rather than taking a risk on potential talent that has yet to be fully exhibited. I'm *not* saying they don't take students like this, I'm just saying it's a risk and therefore rarer. You may well deserve to be at Oxford, but if that's the case, there's no rush. Take a year or two to tidy up the aftermath like I did and I guarantee you'll have much better success with the admissions process. Just one question - are the grades you're talking about your actual A-level grades or AS/predicted grades?

Achieved A level grades. I am also doing a resit for one and predicted an A*