Matthews said during an interview on SiriusXM NFL Radio that the diagnoses by Philadelphia Eagles' doctors caused lingering knee and ankle damage that limited his production once he was traded to the Bills.
The 25-year-old missed a month in the middle of last season due to thumb surgery. His campaign came to a premature end in December due to the continued knee issues, he claims.
"I think the worst and most frustrating thing about the whole situation was, when I got to Buffalo, I was still dealing with the things that I had to get surgery on," Matthews said. "But I had two really bad diagnoses on the knee and the ankle, so going into the trade, I thought they were both things that were going to heal on their own. But once I got around Buffalo's doctors, they got me in touch with the right people and then I got really good feedback.
"We ended up finding out there were other things that I was dealing with, so the thumb was definitely upsetting, the chest was upsetting. But what's crazy was when they ended up doing my surgery on my knee, they actually told me that, 'Man, it's a good thing that you didn't play more games, you didn't practice more, because you needed to come here and get this procedure done as soon as possible.' So, if anything, it was a blessing in disguise. I don't regret any of the times that happen. I think it honestly has just made me a stronger person, it's going to make me a better player."
Matthews recorded 25 receptions for 282 yards and one touchdown in 10 games last season after being acquired along with a third-round pick in a deal for cornerback Ronald Darby in August.