Skip to content
HCC Buddy home

M18.12

Billable

Unilateral primary osteoarthritis of first carpometacarpal joint, left hand

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

What This Code Means

Wear and tear arthritis of the joint at the base of the thumb on the left hand, not caused by injury or other conditions.

Coding Tips

  • •This code specifies primary osteoarthritis, meaning it developed without a prior injury or underlying disease
  • •The '12' suffix indicates left hand involvement; use M18.11 for right hand primary osteoarthritis

Code Hierarchy

└M18Osteoarthritis of first carpometacarpal joint└M18.1Unilateral primary osteoarthritis of first carpometacarpal joint└M18.12Unilateral primary osteoarthritis of first carpometacarpal joint, left hand
└M18.12Unilateral primary osteoarthritis of first carpometacarpal joint, left hand

Open M18.12 in the Interactive Encoder

See full code details, AI coding tips, HCC mappings, and related codes in our interactive encoder. Start your 14-day Pro trial — no credit card required.

Open in EncoderStart 14-Day Pro Trial