All Blacks lock Sam Whitelock is on his way to Japan after recovering from an ear issue - caused by trampoline use - which he says affected his balance.
Whitelock was one of several All Blacks to delay their departures for the northern tour - the three Barrett brothers have a family bereavement, while Will Jordan also has an inner ear problem - with wing Leicester Fainga'anuku replaced by Mark Telea due to what has been described as a family emergency.
In explaining his issue ahead of the Test against Japan in Tokyo on Saturday, Whitelock said it was related to playing on a trampoline with his children, after which he felt dizzy.
He said he spent the next five days in bed, sleeping morning and night for a couple of hours.
"Long story short, there are some little crystals in your ears, in your inner ear, and they all got into a little bit of a weird funk," he said. "That's why I lost a little bit of balance, my vision was pretty blurred, and it took a little time to get right.
"But I had some amazing people help me get it right, people in Christchurch, people in Auckland. Everyone's given me some space to get it right, and now I'm looking forward to getting back to the team environment and getting into some contact."
He said former teammate Ben Smith had similar problems a few years ago. Initially, Smith believed the symptoms were caused by concussion. Some exercises can help correct the issue.
"From my little bit of knowledge, there are three inner ear canals and each of them affect your balance and sight differently," Whitelock said. "You have to work out which one it is, and then go through different protocols and exercises to get it right."
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