Can I get my job back?

[Rumpogumpo]

After 19years in the business I was given the chance of ihr due to a back problem.I had been on the sick for about 8 months with regular contact with management and atos. During this time I had intense physio and was recovering well. Atos then arranged for me to have an MRI scan to see how my back was doing. Shortly afterwards atos contacted me again with the bad news( so I was lead to believe)!!! My back was severely damaged with excessive degeneration of the discs and was advised to take the ihr because in his eyes I wouldn't be able to go back on delivery. At the time I was devastated and after the phone call (not a face to face meeting) I thought that was the only option I had .needless to say it wasn't long before my manager contacted me with my ihr figure.where was the union I hear you ask .Too busy sorting out the office revision so with reluctance I took up the offer of the ihr. I wasn't offered any adjustments to my duty or indoor work ,In fact it just seemed like I was just another full timer out the door! Anyway to cut along story short after leaving the business I have seen 2 different back specialists and various physios and have showed them the results of my MRI scan and they all came to the same conclusion that my back was not severely damaged and there is no reason why I can't return to work. Maybe not in the same role but the business should have made adjustments to meet my needs! I feel like have been let down by my union big style because they should have informed me of my rights and I think Royal Mail and atos have stitched me up like a kipper. Does anyone have any advice for me,a frustrated ex postie?