“Holy s--t, that’s actually my doctor. What a badass!” That was what Foo Fighters frontman Dave Grohl had to say after his orthopedic surgeon, Dr. Lew Schon, performed the White Stripes' “Seven Nation Army” onstage with the Foos during their July 19 show at Boston’s Fenway Park. Dr. Lew not only impressed Grohl, but his rousing performance (which you can watch above) had the crowd yelling “Lew,” in a way similar to Bruce Springsteen fans adoringly yell “Bruce.”

Before the song began, Grohl told those in attendance how Dr. Lew came to be onstage with them that night. "My orthopedic doctor is here tonight okay," explained Grohl. "The man that made it possible for me to get onstage and play a show tonight. Now, he came to my hotel room today and he f--king checked out my leg and he said, 'You can rock Fenway tonight' and I said, 'Lou, so can you.'"

The band seem to be having the time of their lives on this current North American tour and in an interview with Entertainment Weekly, Grohl confirmed that fact. “The shows we’ve been doing lately are some of our favorite shows we’ve ever done, and I’m not f--king kidding," he said. "We talk about this after every show in the dressing room. What seemed like some sort of set back at the time has turned into this beautiful blessing in disguise, where this throne and these crutches and these audiences make us play longer and harder than we ever have. It’s this whole new energy in the show.”

Foo Fighters’ 2015 North American tour started on July 4 and since then almost every show has included something new and special. Grohl’s broken leg guitar solo, guest appearances by Chad Smith of Red Hot Chili Peppers and Bad Brains members, and lest we forget Grohl and his giant guitar and light adorned throne. Loudwire was on hand at the group’s recent Citi Field show in NYC. Check out our exclusive photos from the performance and the inside scoop here.

Foo Fighters play two shows in Japan this week to round out their July dates. They will then pick up their North American tour once more in Edmonton, Canada on Aug. 12. Check out a list of their tour dates here.

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