From the age of about 19 an arthritic condition, ankylosing spondylitis, started to eat away at my spine and hip joints. For the next 8 years, there were prolonged periods of increasingly severe pain, as my vertebrae and hip joints all fused. For half of that time I did not know what was causing the pain, as I had a rather primitive doctor who thought that, as a mere patient, I had no right to know the cause of my bouts of sleepless agony and sometimes reduced ability to walk.

In the darkness of ignorance, there were nights when I woke yelling with the excruciating pain in my back as the vertebrae, one by one, went through their unrelenting process of fusing together. In the day time, I may commence a step while trying to walk, only to pull up half way through because of the sudden surge of pain in one or other of my hip joints.

Despite that suffering, I managed to keep a positive attitude at all times, and I do not recall ever feeling unhappy. Can recall that one day at 20, I did wonder if I would ever have a day without pain again, but that was more of an inquisitive question than an inkling of despair. I always told myself, even assumed, that one day things would be just fine.

From the age of 24 I knew what the cause was, ankylosing spondylitis. As I moved house, I changed doctors, who was both kind and helpful, and who talked openly, even providing leaflets about the condition. There was much an individual could do to help relieve the condition and slow down or stop it's destructive path. However, my old doctor had not told me that, so years were wasted when could have been doing exercises that may have helped.

I also learnt that I was unlucky; it was quite rare for the condition to be so bad, and especially to destroy someone's hip joints. Gradually, the condition deteriorated, and for most of my 27th year I could just about shuffle short distances with walking sticks, but no more.

Severe pain can be a great source of negative thoughts, yet throughout those years, I never once allowed myself to think negatively about my long term future. One day, I always told myself, the pain would be taken away and I would be back to normal. Yet, up to the age of 26, I had no idea there was such a thing as a hip replacement operation. When I was told there was, I was also told, in 1977, that surgeons did not like to use the operation on young people, as its longevity was not known.

With my encouragement, the surgeon finally agreed not only to operate, but to replace both hips together, something he had never even done before. I assured him I would be fine, and that is what I wanted.

As I waited for the operation, my positive thinking was elevated to such an extent that, the night before the operation, I felt like a child on Christmas Eve, wanting to fall asleep while Santa Claus came and did his duty. Santa Claus, in the form of my wonderful surgeon, arrived at 10 am the next morning.

I can still recall to this day looking up at the clock in the theatre ante-room at 10 am. Inside I felt calm, and anticipating final release from the years of pain. A moment later I looked at the clock again, and it read 2pm. I gave a little laugh to the lovely nurse who was holding my hand. "Oh, still not started?" I asked.

Her beautiful smile said it all: "It's all over, Roy."

Within weeks after the operation I was back to normal. No pain, no noticeable disability, and feeling on top of the world. But I had always known it would be like that.

Can I prove that was all or partly due to positive thinking? No, of course not. But then, there is no need to prove something to myself that I know. I was happy and content to be rid of years of pain.