Answer: National Medicare policy, as reflected in the Physician Fee Schedule database, does not establish a formal global period for unlisted-procedure codes such as 22899 (Unlisted procedure, spine).
Rather, national Medicare assigns such codes a "YYY" global period, meaning that the individual carrier "is to determine whether the global concept applies and establishes postoperative period, if
appropriate, at time of pricing," according to CMS guidelines.
In other words, the payer can determine whether a global period applies and what kind of global period to impose when you submit an unlisted-procedure code.
In most cases, the payer will assign a 90-day global period for major procedures, such as kyphoplasty. You can attempt to influence the payer's decision by noting the global period for similar procedures when submitting your claim. (For instance, kyphoplasty closely resembles percutaneous vertebroplasty [such as 22520, Percutaneous vertebroplasty, one vertebral body, unilateral or bilateral injection; thoracic], which has a 90-day global period.)
If the payer does institute a global period, you should not report follow-up visits during that designated period as separate services. Don't make assumptions about your payer's rules, however.
For example, NHIC, a Part B carrier in California, does not impose any global period on kyphoplasty. In such a case, you may legitimately seek reimbursement for follow-up visits using the appropriate E/M service code (for example, 99213, Office or other outpatient visit for the evaluation and management of an established patient ...).
The lesson here is to get your payer's guidelines in writing and follow them consistently. Like everything else involving unlisted-procedure claims, this will require extra effort, but taking the extra step will also ensure the best reimbursement and ensure that you will not face charges of fraudulent coding.