patient with a pre-morbid disability

Whilst on my orthopaedic prac, i treated a patient who was quite disabled. He had been involved in a car accident and had a broken NOF, however was also wheel-chair bound most of the time pre-morbidly. He came across as having a mental disability as well and so when i first saw him, i used very simple language and treated him like someone who had a mental disability. After my first treatment session with him, his mum told me that he was actually fine mentally and quite intelligent. This was rather embarrassing for me as i had been treating a 19 year old like a 5 year old. It was still hard when i treated him later on because i would start using really simple words and then have to remind myself that he actually had near perfect cognition. This taught me just to take extra care when working with people with a disability and to properly check what their disability is before you see them. This would just help this happening again in the future and will help us gauge the best way to interact with them.