Carl Froch has spent three hours in a United States hospital ahead of his fight with Glen Johnson on Sunday.
The 33-year-old is defending his world super-middleweight title in Atlantic City in a Super Six semi-final.
Froch told BBC Radio Nottingham: "I have just come out of the hospital but it was nothing serious.
"I had a bit of a blocked left eardrum from a couple of punches I took. I think a bit of wax was pushed against the eardrum so I had that cleaned out."
The Nottingham boxer is looking to retain his crown, after winning it for a second time with a unanimous points win over Arthur Abraham in Helsinki in November.
Despite the hospital visit, Froch is keen to allay fears about the seriousness of a problem with his ear.
"I feel unblocked, clear headed and back in balance again, so other than that I feel in tip-top shape and ready for business on Saturday night," he said.
"You are never 100%. All top sportsmen carry injuries but I have not had anything really hindering me.
"I feel really good. It is at this stage if you struggle at the weight you start to feel a bit weak and tired, and your legs feel really drained.
"But I have done the weight really well. It is just about fine tuning and I am happy with where I am at.
"There was about two to three hours waiting around and they wouldn't let me go out of there [the hospital] until I filled out the forms.
"[It cost me] a couple of hundred bucks . Everything is a couple of hundred bucks out here, whether you are tipping the valet guy, croupier, concierge or going for a massage.
"I was given a boost to see Glen Johnson running down the beach in the heat with his tracksuit on, sweating, so he's obviously struggling with the weight and shedding some pounds."