The codes
| Code | Used for | Base units |
|---|---|---|
| 01382 | Diagnostic knee arthroscopy | 3 |
| 01400 | Open or surgical arthroscopic knee procedures | 4 |
Base units shown are the standard values most payers use. Check your payer and the current year's CMS base unit file before relying on them.
Picking between them
If the surgeon only looked, it's 01382. If they repaired or removed anything, like a meniscectomy, ACL reconstruction or debridement, it's usually 01400. Code from the operative note, not the schedule. Cases often change once the surgeon looks inside.
Blocks for ACL repairs
ACL reconstructions often get a block for pain after surgery. It may be separately billable when the surgeon requests it and it isn't the main anesthetic. See nerve block billing.
Volume matters
These are short, high-volume cases. A billing error of one unit per case quietly costs you hundreds of units a year. Check a sample each month against the records.
This article is general information, not billing, legal or tax advice. Payer rules change; always check current guidance.
Sources
- CMS: Medicare Claims Processing Manual, Chapter 12 (Anesthesia)
- Maryland Workers' Compensation Commission: anesthesia base unit values