Find policies, billing codes, payers, states, and providers
CPT 29435: Walking Cast for Tibia and Fibula Shaft Fractures
CPT code 29435 represents the application of a walking cast that immobilizes the lower leg and foot while permitting knee flexion, commonly used for tibia and fibula shaft fractures. Nationally, this code captures a commonly performed orthopaedic procedure that enables stabilized weight-bearing to promote fracture healing while maintaining knee mobility. Accurate coding affects clinical documentation, billing consistency, and payer coverage determinations for fracture management.
Key payers addressed in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical context for use of a walking cast, comparisons to related cast application codes, common billing modifiers encountered, and typical sites of service for this procedure. The publication also summarizes relevant ICD-10 diagnoses that commonly pair with this code and highlights operational considerations for orthopaedic surgery practices.
This summary is written for a national audience and focuses on the code definition, typical clinical indications, and the aspects of billing and documentation that influence claim adjudication and reporting across major public and private payers.
Customize your policy alerts
Sign up for cpt 29435 policy alerts
Get alerted when payer policies referencing 29435 are released or updated.
Monitor payer policy activity
Billing Code Overview
CPT code 29435 describes the application of a walking cast that immobilizes the lower leg and foot while allowing knee motion. The cast is used in the treatment of tibia and fibula shaft fractures and includes an anterior segment that extends over the knee while covering the lower leg. The device design applies controlled pressure at the fracture site to stimulate callus formation during ambulation.
Service type: Cast application for lower leg fracture (walking cast / weight-bearing immobilization)
Typical site of service: Hospital outpatient department, ambulatory surgery center, or orthopedic clinic / procedure room
National Reimbursement Benchmarks
Medicare’s mean rate of $143.7 sits well below BUCA’s average commercial mean of $305.2, indicating a substantial gap between federal reimbursement and this commercial benchmark for CPT 29435. This gap reflects a common pattern where large commercial networks pay materially more than Medicare; here the difference is $161.5 in mean rates, with BUCA roughly double Medicare on average.
Dispersion analysis (P75 minus P25) highlights variability across payers: Blue Cross Blue Shield has the widest interquartile spread at $162.5 ($520.6 - $348.1), followed by BUCA at $136.2 ($376.2 - $236.0). UnitedHealth Group and Cigna show intermediate spreads of $107.4 ($225.2 - $114.8) and $110.1 ($222.5 - $114.4) respectively, while Aetna is the tightest at $73.4 ($103.4 - $30.0). Medicare’s P75–P25 is $16 ($150 - $134), indicating the least variation among listed payers.