An unusual video has emerged of Dave Grohl's orthopaedic surgeon - the man treating his broken leg - performing The White Stripes' 'Seven Nation Army' at a Foo Fighters gig in Boston, MA, US on Sunday.

The footage, captured by a member of the audience at Boston's Fenway Park, shows Dr. Lew C. Schon singing the blues rock hit after being brought onto the stage by the band.

After the bizarre performance, Grohl can be heard saying ""Holy s***, that's actually my doctor,"

Writing online about the video, the filmer said "Foo Fighters wrapped up the July leg of their stadium-filling "Throne" tour Sunday night with a second show at Boston's Fenway Park, where the band paid homage to the man who practically made this trek possible: Dave Grohl's orthopedic surgeon.

"Midway through Foo Fighters' set, Grohl invited Dr. Lew C. Schon, who helped the rocker after Grohl seriously injured his leg in Sweden, onstage to lead the band in a spirited rendition of White Stripes' "Seven Nation Army."

An unusual video has emerged of Dave Grohl's orthopaedic surgeon - treating his broken leg - performing The White Stripes' 'Seven Nation Army' at a Foo Fighters gig in Boston, Massachusetts on Sunday.

The footage, captured by a member of the audience at Boston's Fenway Park, shows Dr. Lew C. Schon singing the blues rock hit after being brought onto the stage by the band.

After the bizarre performance, Grohl can be heard saying ""Holy s***, that's actually my doctor,"

Writing online about the video, the filmer said "Foo Fighters wrapped up the July leg of their stadium-filling "Throne" tour Sunday night with a second show at Boston's Fenway Park, where the band paid homage to the man who practically made this trek possible: Dave Grohl's orthopedic surgeon.

"Midway through Foo Fighters' set, Grohl invited Dr. Lew C. Schon, who helped the rocker after Grohl seriously injured his leg in Sweden, onstage to lead the band in a spirited rendition of White Stripes' "Seven Nation Army."