CPT code 27871 denotes a tibiotalar arthrodesis — a surgical fusion of the tibia and fibula at the ankle — performed to relieve pain and restore stability in patients with end-stage ankle pathology. The code is relevant across surgical orthopedics and impacts reimbursement, utilization monitoring, and care pathway design nationally because it represents a definitive, often resource-intensive, operative treatment for debilitating ankle conditions. Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical intent and typical settings for the service, common billing considerations, payer coverage patterns and benchmarks where available, and related coding and policy context that affect claims processing and prior authorization practices. The summary highlights clinical indications for fusion versus joint-preserving alternatives, expected sites of service (hospital operating room or ambulatory surgery center), and typical components of the billed service. Data not available in the input is noted where applicable. This publication is intended to inform billing staff, case managers, and policy analysts about coding, coverage framing, and operational considerations tied to CPT code 27871.