Heidi Harbison Kimberly, HMS instructor in medicine at Brigham and Women’s Hospital and Mark Gebhardt, the Frederic W. and Jane M. Ilfeld Professor of Orthopedic Surgery at HMS and chief of the Department of Orthopedic Surgery at Beth Israel Deaconess Medical Center, are HMS physicians who played a role in the Boston Marathon day events. They are also musicians who play in the Longwood Symphony Orchestra, an elite ensemble that draws most of its performers from Boston’s medical community.