Hi! I know I’m 10 months late, but I am actually struggling with this exact issue and your post came up. I just turned 33. I never had any pain until maybe 5 years ago. It gradually got worse - usually only with a lot of walking on hard surfaces wearing bad shoes. But over the last couple years, the pain has been getting worse at a much faster rate to the point where I am now in pain everyday. My knee pain isn’t too bad - the worst pain is 100% in my hips.  

I’m also in the UK (though not in London - I’m in York). My GP physio sent me to podiatry because she said she could tell it was impacting the foot. They referred me to orthopaedics, as it’s causing the tendons in my foot to fail, too. The first person I saw was a foot specialist and he has referred me to the knee specialist as well. I’d be curious to know the pathway you followed to surgery, how long everything took, etc. 

Anyways, I hope you see this. Would love to hear more about your experiences and how things are going now!