Application of a long leg cast (walker type) extending from the thigh to the foot, shaped at the base to allow weight-bearing ambulation via a cast shoe or rubber heel/footplate.

Verified May 8, 2026 · 5 sources ↓

Medicare: $154.65
Total RVUs: 4.63
Global, days: 0
Region: Knee

Drawn from CMSMdclarityAAPC

Documentation requirements

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

Source · Editorial brief grounded in 5 cited references ↓

Diagnosis driving immobilization — fracture site, deformity, or post-operative indication — with corresponding ICD-10 code
Laterality explicitly documented (left, right, or bilateral) to support LT/RT modifier on the claim
Cast type noted as 'walker' or 'ambulatory' with description of the weight-bearing mechanism (cast shoe, rubber heel, or footplate)
Weight-bearing status and clinical rationale — document whether ambulation is permitted and why the walker-type cast was selected over a non-walking cast
Extent of the cast — note that it extends from the thigh to the foot with toes free
If modifier 22 is used, document the specific factors that made the application substantially more complex than typical (e.g., severe edema, deformity, uncooperative patient)

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 25 Significant separate E/M 50 Bilateral procedure 51 Multiple procedures 52 Reduced services 59 Distinct service 76 Repeat, same physician 77 Repeat, another physician LT Left side RT Right side KX Documentation on file

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 29355 covers the application of a long leg ambulatory cast — sometimes called a walking cast — that immobilizes the knee and leg from the thigh down to the foot while leaving the toes exposed. The base of the cast is formed to accept a cast shoe or fitted with a rubber heel and footplate, enabling the patient to bear weight and walk when clinically appropriate. This distinguishes 29355 from 29345, which is a non-walking long leg cast.

Primary indications include stabilization of femoral, tibial, or fibular fractures, post-reduction immobilization, and management of lower extremity deformities. The 000 global period means no bundled follow-up is included — each subsequent cast change or manipulation visit is separately billable. Because the code sits on the CMS therapy cap list (per the Medicare Claims Processing Manual), claims billed under a therapy provider type may be subject to financial limits and require appropriate modifiers.

Side-specific modifiers (LT/RT) are expected on virtually every claim. Bilateral application of long leg casts is unusual but would use modifier 50 on a professional claim. When cast application accompanies a separately identifiable E/M on the same date, append modifier 25 to the E/M — not to 29355 itself.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	1.49
Practice expense RVU	2.86
Malpractice RVU	0.28
Total RVU	4.63
Medicare national rate	$154.65
Global period	0 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	$154.65
HOPD (APC 5102) Hospital outpatient department	$285.75
ASC (PI P3) Ambulatory surgical center (freestanding)	$96.00

Common denial reasons

The recurring reasons claims for CPT 29355 get rejected.

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

Missing or mismatched laterality — claim lacks LT or RT modifier while diagnosis code specifies a side
Bundling with a same-day fracture treatment code when the cast application is considered included in the fracture care procedure
ICD-10 diagnosis does not support long leg immobilization (e.g., diagnosis limited to the ankle when a short leg cast would be appropriate)
Billed under a therapy provider type without addressing therapy cap requirements or missing KX modifier when cap is exceeded
Duplicate claim or missing modifier 76/77 when cast was reapplied the same day by the same or different provider

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01What is the difference between CPT 29355 and CPT 29345?

29345 is a standard long leg cast not designed for weight-bearing. 29355 is the walker version — the base is shaped for a cast shoe or fitted with a rubber heel so the patient can ambulate. If you applied a footplate or cast shoe, use 29355. If the patient is strictly non-weight-bearing and no walking accommodation was made, use 29345.

02Does CPT 29355 have a global period?

The global period is 000 — meaning zero post-operative days are bundled. Each return visit for cast change, adjustment, or follow-up is separately billable and does not require modifier 24 or 79 to escape a global.

03Can 29355 be billed on the same day as a fracture treatment code?

Generally no. Cast application is considered included in fracture treatment codes that have their own global periods. Bill 29355 separately only when it is truly a standalone service unrelated to a same-day fracture care procedure, or when the fracture treatment code bundles in the cast and you are billing a distinct subsequent application.

04Is modifier 50 appropriate when both legs are casted?

Yes, but bilateral long leg casting is rare. On a professional (1500) claim, append modifier 50 to 29355. In an ASC setting, follow NCCI guidance and bill two lines — one with LT and one with RT — each with one unit of service.

05Why does 29355 appear on the Medicare therapy cap list?

CMS includes 29355 among codes that can be billed under therapy benefit categories. When a physical or occupational therapist applies the cast and bills under a therapy provider type, the claim may count against the therapy financial limit. Append modifier KX once the cap threshold is met and documentation supports medical necessity for continued care.

06If the cast needs to be reapplied the same day due to cracking or patient movement during application, what modifier is used?

Use modifier 76 if the same physician reapplies the cast on the same date, or modifier 77 if a different physician performs the reapplication. Document the reason for repeat application in the note.

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 cast type (walker versus non-walking), the weight-bearing mechanism applied (cast shoe, rubber heel, or footplate), explicit laterality, the extent of immobilization from thigh to foot with toes free, and the clinical indication driving the choice of long leg over short leg immobilization. Capturing these details at dictation prevents the two most common denial triggers: missing laterality and a diagnosis-to-procedure mismatch where the documented injury doesn't justify full long leg immobilization.

See how Mira captures CPT 29355 documentation