Summary & Overview
CPT 26665: Open Repair of Thumb Metacarpal Base Fracture with CMC Dislocation
CPT code 26665 denotes an open surgical repair for fractures at the base of the thumb metacarpal with reduction of an associated carpometacarpal (CMC) joint dislocation. This procedure is a common hand surgery intervention after traumatic injury and carries implications for operative planning, device use (for example, pins or small nails), and post‑operative rehabilitation. Nationally, accurate coding for this operation affects surgical quality measurement, facility billing, and payment across major payers.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical context for the procedure, typical sites of service, and an overview of common billing modifiers encountered with operative hand procedures (modifier list provided in input). The publication presents benchmarks for coding frequency and utilization where available, highlights policy considerations relevant to surgical reconstruction of the thumb CMC joint, and summarizes documentation elements commonly required for medical necessity and claim adjudication.
The content is aimed at coding professionals, surgical practices, and health plan policy staff seeking clarity on the clinical intent of CPT code 26665, expected care settings, and areas that frequently prompt payer review or inquiry. Data not available in the input is clearly noted in relevant sections.
Billing Code Overview
CPT code 26665 describes an open repair of a fracture at the base of the thumb with reduction of a dislocation of the carpometacarpal (CMC) joint. The procedure involves an open incision to access the thumb metacarpal base and adjacent carpal articulation; the surgeon may use small nails or wires to secure and stabilize the bones after reduction.
Service type: Surgical procedure — open reduction and internal fixation of thumb metacarpal base fracture with CMC joint dislocation
Typical site of service: Hospital operating room or ambulatory surgery center (outpatient/inpatient surgical setting)
Clinical & Coding Specifications
Clinical Context
A 34-year-old right-hand-dominant male sustains a direct blow to his right thumb during a bicycle crash, presenting to the emergency department with severe thumb pain, swelling, deformity at the base of the thumb, and limited thumb motion. Radiographs demonstrate a displaced fracture of the base of the first metacarpal with dorsal dislocation of the first carpometacarpal joint. Closed reduction attempts in the ED are unsuccessful due to instability. The orthopaedic hand surgeon schedules an open reduction and internal fixation.
The patient is brought to the ambulatory surgical center (or hospital operating room for more complex injuries). Under regional block or general anesthesia, the surgeon makes an open incision over the first carpometacarpal region, debrides interposed tissue, reduces the fracture-dislocation, and secures the metacarpal with small K-wires or mini-screws as needed. Intraoperative fluoroscopy verifies alignment. The wound is irrigated and closed; a thumb spica splint or cast is applied. Postoperative care includes analgesia, immobilization, wound checks, and hand therapy referral for range-of-motion and strengthening once healing permits.
Typical site of service: ambulatory surgical center or hospital operating room.
Service type: open surgical repair (open reduction and internal fixation) of base of first metacarpal fracture with carpometacarpal dislocation using internal fixation (nails/wires).
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
LT |