I am reviewing the utilization of CPT PC's 46930, 46945, 46946 and 46947, all which have a 90 day global. However, I see many providers appending modifiers -58 and -78. Initially, it appears that the provider has found a way to optimize his/her reimbursement. I find it difficult to believe that the above procedures could be 'staged'...? If a coder/biller in this field could discuss this rational, I would appreciate it. I think these codes are on the RAC hit list for a reason. Any thoughts??