Here is what the AAOS has to say about bmp - they bundle it into all procedures:

"preparation and insertion of synthetic bone substitutes, osteoconductive and osteoinductive agents (eg, hydroxyapatite, calcium phosphates, coral, methylmethacrylate, demineralized bone matrix, bone morphogenetic proteins), except where specifically excluded (eg, 20930, 20931)"

Above is #11 in the Intraoperative services included in the global service package