Open epiphysiodesis of the distal tibia — surgical arrest of the tibial growth plate to correct or prevent limb-length discrepancy during skeletal growth.

Verified May 8, 2026 · 7 sources ↓

Medicare: $561.14
Work RVU: 7.51
Global, days: 90
Region: Foot & ankle

Drawn from CMSFastrvuAAPCFindacodeMdclarity

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Specify which physis was targeted — distal tibia, proximal tibia, or both — and confirm it was open at the time of surgery.
Document the surgical technique by name: stapling, percutaneous screw epiphysiodesis, or open physeal resection/curettage.
Record the clinical indication with pre-op leg-length discrepancy measurements and the projected discrepancy at skeletal maturity using bone age assessment.
Document laterality explicitly (left vs. right) in both the operative note and the diagnosis coding.
Include intraoperative fluoroscopic confirmation that hardware or resection was placed at the correct physis.
Note patient's skeletal age (bone age X-ray) and estimated remaining growth to justify timing of the procedure.

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 58 Staged or related 59 Distinct service 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon LT Left side RT Right side XS Separate structure

What this code covers

Source · Editorial summary grounded in 7 cited references ↓

CPT 27730 covers open surgical arrest of the tibial epiphysis (epiphysiodesis), performed to stop longitudinal growth of the tibia. The goal is limb-length equalization: by fusing or stapling the distal tibial growth plate, the surgeon allows the shorter contralateral limb to catch up, or prevents further length divergence before skeletal maturity. This is nearly always a pediatric procedure — growth plates must still be open and active for the intervention to have its intended effect.

Patient selection depends on predicted limb-length discrepancy at skeletal maturity, remaining growth potential (bone age), and the specific physis being targeted. The distal tibia is the most common tibial site, but operative notes must specify which physis was arrested and the method used (stapling, screw epiphysiodesis, or open resection of the physis). Laterality is almost always unilateral; document LT or RT accordingly.

The 90-day global period covers all routine postoperative management through day 90. Staged procedures on the contralateral tibia — planned from the outset — require modifier 58. Unplanned returns to the OR for a related complication within the global window use modifier 78. Unrelated same-session procedures need modifier 59 or XS to break bundling.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU vs. total RVU

The work RVU (7.51) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (16.8) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	7.51
Practice expense RVU	7.68
Malpractice RVU	1.61
Total RVU	16.8
Medicare national rate	$561.14
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	$561.14
HOPD (APC 5113) Hospital outpatient department	$3,342.87
ASC (PI J8) Ambulatory surgical center (freestanding)	$2,084.06

Common denial reasons

The recurring reasons claims for CPT 27730 get rejected.

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

Missing or inconsistent laterality documentation — claim lacks LT/RT modifier or operative note conflicts with the claim form.
Medical necessity not established — no bone age study, no leg-length measurement series, or no documented projected discrepancy at skeletal maturity in the chart.
Incorrect code selection — 27730 is an open epiphysiodesis; percutaneous screw techniques or arthroscopic approaches may map to different codes and using 27730 for those triggers downcoding.
Global period conflict — subsequent ipsilateral procedures billed without modifier 58, 78, or 79 as appropriate, triggering automatic bundling denial.
Age-related payer edit — some commercial payers flag this code when billed for skeletally mature patients (closed physes), requiring additional documentation or appeal.

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 7 cited references ↓

01Is 27730 ever billed bilaterally with modifier 50?

Rarely, but it is anatomically possible when both tibial physes are arrested simultaneously to manage bilateral limb-length issues. If both sides are done in one session, append modifier 50 and confirm your payer accepts bilateral billing for this code — some carriers require separate line items with LT and RT instead.

02What ICD-10 diagnosis codes typically support 27730?

M21.00–M21.069 (limb-length discrepancy) and Q74.2 (congenital limb deformity) are the most common supporting diagnoses. Acquired causes such as post-traumatic growth disturbance (M89.20–M89.269) or post-infectious physeal damage also apply. Payers want to see the underlying etiology coded alongside the limb-length discrepancy.

03What is the global period for 27730 and what does it include?

27730 carries a 90-day global period. That covers the day-of and day-before surgery visits, the procedure itself, and all routine post-op care through day 90 — including wound checks, staple/suture removal, and standard follow-up imaging reviews. Bill unrelated E/M visits in the global window with modifier 24.

04Can 27730 be billed same-day with a contralateral limb procedure?

Yes. If a contralateral procedure (e.g., lengthening or epiphysiodesis of the fibula) is performed the same day, bill the highest-RVU code first, then append modifier 51 and 59 or XS to the secondary code to indicate distinct procedural services. Confirm NCCI edits for the specific code pair before submitting.

05How does modifier 58 apply if a staged contralateral epiphysiodesis is planned?

If you document in the original operative report or pre-op note that a contralateral tibial epiphysiodesis is planned as a staged procedure, bill the second surgery with modifier 58 when it occurs within the 90-day global of the first. Modifier 58 signals a planned staged procedure, reopens reimbursement, and avoids the automatic global-period denial that would fire without it.

06Does 27730 require fluoroscopy to be bundled or can it be billed separately?

Intraoperative fluoroscopy (77002) used to confirm hardware placement at the physis is typically bundled with the surgical code under NCCI edits. Separate billing for fluoroscopic guidance requires modifier 59 and documentation that it was a distinct, separately identifiable service — but most payers will deny it as inclusive. Check your MAC's local coverage policy before billing 77002 alongside 27730.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the targeted physis, surgical technique (stapling vs. screw epiphysiodesis vs. open resection), laterality, intraoperative fluoroscopy confirmation, pre-op leg-length discrepancy measurements, and bone age data from the dictation. That documentation directly prevents the two most common denials for 27730: missing medical necessity evidence and laterality mismatches between the operative note and the claim.

See how Mira captures CPT 27730 documentation