CPT 27420
Revision of unstable kneecap
CPT 27420 at a glance
- Code
- 27420
- Code type
- CPT/HCPCS
- Short descriptor
- Revision of unstable kneecap
- Category
- ASC Surgical
- ASC payment status
- Payable in an ASC (surgical)
- CMS addendum
- AA (Surgical)
- Typical setting
- Ambulatory surgery center (POS 24) or hospital outpatient department (POS 22).
What is CPT code 27420?
CPT 27420 is a CPT/HCPCS procedure code. Its official CMS short descriptor is "Revision of unstable kneecap". In the ASC context it is grouped under ASC Surgical.
Is CPT 27420 payable in an ambulatory surgery center (ASC)?
CPT 27420 appears on Medicare's ASC Covered Procedures List (CMS Addendum AA), so Medicare reimburses it when the surgery is performed in a certified ambulatory surgery center.
Where is CPT 27420 typically performed?
Ambulatory surgery center (POS 24) or hospital outpatient department (POS 22).
Which specialties use CPT 27420?
CPT 27420 is most associated with General Surgery, Ortho – Adult Reconstructive, Orthopaedic Surgery.
Reference information compiled from the CMS April 2026 ASC payment addenda (AA, BB, EE). Codes, descriptors, and ASC payment status change with each CMS update. This is a coding reference, not billing, coding, or legal advice. Always verify against the current CMS addenda and individual payer policy before billing. CPT is a registered trademark of the American Medical Association.