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M43.21

Billable

Fusion of spine, occipito-atlanto-axial region

This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).

What This Code Means

A surgical procedure where the bones at the very top of the spine (where the skull connects to the neck) are fused together to provide stability.

Coding Tips

  • This code represents fusion at the occipito-atlanto-axial region (skull-C1-C2); verify operative reports for exact levels fused
  • Often used for atlantoaxial instability or upper cervical pathology; document the clinical indication

Code Hierarchy

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