Open arthrotomy of the ankle with posterior capsular release, performed with or without concurrent Achilles tendon lengthening.

Verified May 8, 2026 · 6 sources ↓

Medicare: $541.43
Total RVUs: 16.21
Global, days: 90
Region: Foot & ankle

Drawn from CMSAbosAAPCGenhealthFastrvu

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 name the approach as 'posterior' — notes stating 'standard ankle approach' are an audit flag.
Document the specific capsular structures released and describe extent of scar tissue excised.
If Achilles tendon lengthening is performed, record the technique (Z-lengthening, percutaneous cuts, number of incisions) and confirm it was performed through the same operative exposure.
State the pre-operative and intra-operative passive dorsiflexion measurements to justify medical necessity of capsular release.
Record the anesthesia type — general or regional — as some payers require this for facility-level review.
Include pre-operative imaging (X-ray or MRI) in the medical record to support diagnosis of posterior contracture or equinus deformity.

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 50 Bilateral procedure 51 Multiple procedures 59 Distinct service 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

27612 covers a posterior ankle arthrotomy performed to release a contracted or scarred posterior capsule, with or without Achilles tendon lengthening in the same operative setting. The surgeon opens the posterior ankle compartment, excises or releases scar tissue restricting dorsiflexion, and — when the Achilles is contributing to the equinus deformity — lengthens the tendon through open cuts at the same incision. Both components (release and tendon lengthening) are bundled into this single code; do not separately report Achilles lengthening when performed through the same exposure.

The primary clinical indications are posterior ankle equinus contracture, post-traumatic ankle stiffness, and range-of-motion deficits that have failed conservative management. The code sits in the 27600–27612 incision procedures range for the leg and ankle. Closely related codes require careful selection: 27610 is an anterior arthrotomy for drainage or foreign body removal; 27620 adds joint exploration with biopsy or loose body removal; 27625/27626 add synovectomy. Use 27612 only when the operative intent is posterior capsular release, not simple drainage or synovectomy.

The 90-day global period applies. All routine post-op visits, cast or splint changes, and dressing care through day 90 are included. Bill modifier 24 for unrelated E/M visits and modifier 79 for unrelated surgical procedures within the global window. If a distinct, separately identifiable complication requires a return to the OR for a related reason, use modifier 78.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	7.95
Practice expense RVU	7.01
Malpractice RVU	1.25
Total RVU	16.21
Medicare national rate	$541.43
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	$541.43
HOPD (APC 5113) Hospital outpatient department	$3,342.87
ASC (PI A2) Ambulatory surgical center (freestanding)	$1,644.87

Common denial reasons

The recurring reasons claims for CPT 27612 get rejected.

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

Operative note documents an anterior or lateral approach only — payer denies 27612 and downcodes to 27610.
Achilles tendon lengthening billed separately (e.g., 27605 or 27606) on the same claim — NCCI bundles tendon lengthening into 27612 when performed concurrently.
Lack of documented failure of conservative treatment (physical therapy, orthotics, serial casting) before surgical intervention.
Missing range-of-motion measurements in the operative note, leaving medical necessity unsupported on audit.
Procedure billed within the global period of a prior ankle surgery without modifier 79 (unrelated) or 78 (related complication), triggering automatic denial.

Frequently asked questions

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

01Can I bill Achilles tendon lengthening separately when it's done at the same time as 27612?

No. Achilles tendon lengthening performed through the same posterior exposure is included in 27612. Separately reporting 27605 or 27606 on the same date will be bundled by NCCI edits.

02What is the global period for 27612?

90 days. Routine post-op visits, cast or splint changes, and wound care through day 90 are included. Use modifier 24 for unrelated E/M visits and modifier 79 for unrelated surgical procedures during that window.

03How does 27612 differ from 27610?

27610 is an anterior ankle arthrotomy for exploration, drainage, or foreign body removal. 27612 is a posterior capsular release procedure. The surgical approach and therapeutic intent are different — selecting the wrong code based on 'ankle arthrotomy' alone is a common error.

04Is modifier 50 appropriate for 27612?

Yes, if the posterior capsular release is performed bilaterally in the same session. Document clinical justification for bilateral intervention; some payers require prior authorization for bilateral ankle surgery.

05If 27612 is performed during the global period of a prior ankle procedure, which modifier applies?

Use modifier 78 if 27612 is an unplanned return to the OR for a complication related to the original surgery. Use modifier 79 if it is an entirely unrelated procedure performed by the same surgeon during the global window.

06Can 27612 be billed with 27630 (excision of tendon sheath lesion) on the same day?

Potentially yes with modifier 59 or XS if the lesion excision is at a distinct site and separately documented. Confirm NCCI edits for the specific code pair before submitting, as bundling rules apply to same-session ankle procedures.

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 surgical approach (posterior), structures released, extent of scar tissue excised, intraoperative dorsiflexion gain, and — when applicable — the Achilles lengthening technique and number of incisions. This prevents the two most common denials: an operative note that omits the posterior approach (causing a downcode to 27610) and a separate claim for Achilles lengthening that NCCI bundles into 27612.

See how Mira captures CPT 27612 documentation