The Blackburn Rovers right-back described the experience as depressing, explaining that the condition affected both knees when he was 15, leaving him struggling to walk or run.
Doctors could neither establish the cause nor determine whether surgery was necessary.
“They did not know what was going on. I could not run. I could not walk. They did not know if I needed surgery or anything with it because I had pain in both of my knees and they did not know what was causing it. It was non-specific knee pain,” Alebiosu told the Lancashire Telegraph.
“Obviously, it was kind of depressing having about two years of not playing football because of this knee injury. This was when I was about 15 and went on for a couple of years. I could not play.
“It was frustrating because I was a kid and everyone was progressing and I am just waiting to see when this is going to go. I was always hoping for the best, to be honest.”
Alebiosu, 24, joined Blackburn in 2025 and has since made 50 appearances for the Championship club.