Scratching at the same spot?

My dog keeps scratching at the same spot in the corner of our living room, and he doesn’t do this anywhere else. It almost looks like he’s digging when he does it. He lays down there afterwards occasionally, but not majority of the time. He usually looks at us on the couch in the middle or after he does it, like he’s trying to tell us something. He doesn’t whine or bark at it, he just seems curious and slightly concerned.

Some facts about him: -he’s a Great Dane -he’s almost 4 this February -he doesn’t have any known health conditions -he doesn’t behave anxiously