Arthroscopy · Knee

Arthroscopic knee surgery for osteochondritis dissecans: drilling of the lesion with bone grafting, with or without internal fixation, including debridement of the lesion base.

Verified May 8, 2026 · 6 sources ↓

Medicare: $712.44
Total RVUs: 21.33
Global, days: 90
Region: Knee

Drawn from CMSPriorityhealthAAPCEmedny

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 6 cited references ↓

Operative note must confirm arthroscopic approach and identify the specific compartment(s) where the OCD lesion was located.
Document lesion status (unstable, partially detached, or full-thickness separation) to support medical necessity.
Specify drilling technique performed at the lesion base and confirm debridement was performed.
Document whether bone grafting was performed, including graft type (autograft, allograft, or synthetic).
If internal fixation was used, record the type, number, and placement of fixation devices (e.g., absorbable pins, metal screws).
Pre-operative imaging (MRI or X-ray) confirming OCD lesion should be in the record to corroborate diagnosis.

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 59 Distinct service LT Left side RT Right side 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant XS Separate structure

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 29885 covers arthroscopic treatment of an osteochondritis dissecans (OCD) lesion of the knee in which the cartilage fragment has separated or is unstable. The surgeon drills the base of the lesion to stimulate vascular in-growth and bone healing, applies bone graft material, and — when fragment stability requires it — secures the construct with internal fixation (e.g., screws or pins). Debridement of the lesion base is included in the code and cannot be billed separately.

This code sits in the 29870–29887 knee arthroscopy family. Per NCCI policy, codes 29874, 29877, 29879, and 29885–29887 cannot be reported together when the surgical work occurs within the same compartment. Diagnostic arthroscopy (29870) is always bundled into any surgical arthroscopy and is never separately billable. Fluoroscopy used during the procedure is integral — do not bill a separate imaging code.

The global period is 90 days. All routine post-op visits, wound checks, and cast/splint application and removal fall inside that window. Use modifier 24 for unrelated E&M services during the global and modifier 78 for an unplanned return to the OR for a related complication. If a separate, unrelated procedure is performed during the global period, append modifier 79.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	9.95
Practice expense RVU	9.26
Malpractice RVU	2.12
Total RVU	21.33
Medicare national rate	$712.44
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$712.44
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI J8) Ambulatory surgical center (freestanding)	$4,990.40

Common denial reasons

The recurring reasons claims for CPT 29885 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Medical necessity not established — no pre-op imaging or clinical documentation confirming OCD diagnosis and lesion instability.
Unbundling error — 29885 billed alongside 29886 or 29887 for work in the same compartment during the same session.
Diagnostic arthroscopy (29870) billed separately on the same claim; it is always bundled into the surgical arthroscopy.
Fluoroscopy or other imaging coded separately when used intraoperatively — CMS and NCCI consider it integral to the arthroscopic procedure.
Missing prior authorization — many commercial payers require pre-auth for surgical knee arthroscopy; claims without it are denied on submission.

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01Can I bill 29885 and 29886 together on the same knee in the same session?

No. Per Priority Health billing policy and NCCI guidance, 29885–29887 cannot be reported together when the procedures are performed in the same compartment during the same surgical session. Bill only the code that most completely describes what was done.

02Is debridement of the OCD lesion base separately billable?

No. The code descriptor for 29885 explicitly includes debridement of the base of the lesion. Billing a separate chondroplasty or debridement code for the same compartment constitutes unbundling.

03Can I bill for fluoroscopy used to confirm fixation placement during the arthroscopy?

No. Per CMS NCCI policy, fluoroscopy performed during any arthroscopic procedure is integral to the procedure and cannot be billed with a separate imaging code.

04What modifier do I use if the patient returns to the OR within the 90-day global for a related complication?

Use modifier 78. That signals an unplanned return to the OR for a complication related to the original procedure. Modifier 79 is for an unrelated procedure during the global — do not use 79 for OCD-related returns.

05Does the 90-day global period include cast or splint application at the time of surgery?

Yes. Per CPT musculoskeletal system guidelines, application and removal of the first cast, splint, or traction device are included in the surgical code and are not separately reportable.

06Can 29885 be billed with a same-day E&M if the surgeon decides intraoperatively to add bone grafting not originally planned?

A same-day E&M is not appropriate for intraoperative decision-making changes. If the additional work substantially increases the procedure's complexity, document that thoroughly and consider modifier 22 on 29885 rather than adding a separate E&M.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the compartment location of the OCD lesion, lesion stability status, drilling technique, bone graft type used, and whether internal fixation was placed and with what device. That detail prevents the two most common audit flags for 29885: operative notes that omit compartment specificity and notes that fail to document graft application — both of which trigger downcoding or medical necessity denials on post-payment review.

See how Mira captures CPT 29885 documentation