Sue Gilroy has this week received one call-up she was always hopeful of getting – a selection for a fifth Paralympics in Rio this summer – but has also had an invitation she never expected as she has been asked to play for Yorkshire's able-bodied team.

The 43-year-old from Dodworth – who suffers hundreds of dislocations in her joints every day due to Ehlers-Danloss Syndrom, a rare degenerative disease – will compete for Yorkshire against Derbyshire tomorrow with and against able-bodied players.

"I couldn't believe it when the coach rang me and asked me to play for Yorkshire," said Shawlands School teacher Gilroy.

"I asked him if he had got the right person and if he knew I was in a wheelchair. He told me that I had been selected because I had the best averages in the Sheffield League which I play in against able-bodied people. I never ever dreamed I would get that call-up, it wasn't even something I was thinking about but I am incredibly proud. I don't know of any other person like me who has been called up for an event like this. Obviously able-bodied people start against me with a huge advantage because they can move around the table a lot more but I just play to my strengths and try to hit them off the table."

Gilroy's condition is getting increasingly worse but she says playing table tennis every day helps her greatly. He said: "When I have a couple of weeks off I feel much worse. Even when I stop playing at an elite level I will carry on playing just as much because I need to in order to be able to function in day-to-day life. Keeping active eases my condition a lot.

"It's extremely painful and the pain is the most difficult part. I have to have injections because painkillers don't really work on my spinal pain. My wrist dislocates after every other point during a game but I just snap it back in."

Gilroy has won golds at European and Commonwealth level, triumphed in 21 British Championships – with the latest in Grantham last week – and picked up silver at the World Championships in 2014. But she has never won a Paralympic medal despite competing in Sydney 2000, Athens 2004, Beijing 2008 and London 2012. She would love to crown her glittering career with a medal in Rio.

Mum-of-two Gilroy said: "I am playing the best table tennis of my life. "I have beaten the world number one twice this year and I am going from strength to strength. The Olympic medal is the one that has always eluded me. I won't make a definite decision yet but, at the moment, I can't see myself doing another Olympics after Rio. So I want to make it a special one and go out on a high with a medal. I am delighted and thrilled to be called up. It's just fantastic news.

"Shawlands School have been so supportive with letting me have time off. The children were so excited when I told them on Tuesday. They just see me as their teacher and their table tennis coach not a disabled person. I need to thank my coaches and my family, there is no way I could have done it without them."

Gilroy is the first Barnsley person to be selected for Rio and was always one of just a small handful of athletes from the town who had a realistic chance of reaching the Olympics or Paralympics. She said: "Barnsley is a small town compared to others and there aren't that many people who get to the Olympics or Paralympics. I am really proud to be representing Barnsley in Rio."