This came from Matt Hardy's Commentary. You can check it out here

Christian and I currently hold the WWE record for maintaining the longest full-time schedules without missing any time, including major injuries: 5 1/2 years. I’ve been working through my MCL injury, while Christian is currently attempting to battle a bad back. We’ve been competing to see who could work the longest without time off, but our “bump cards” are catching up to us.

Credit: WWE.com