M51.A1 — Intervertebral annulus fibrosus defect, small, lumbar region
M51.A1 is a billable, specific ICD-10-CM code for intervertebral annulus fibrosus defect, small, lumbar region. It is valid for submission on a claim.
Risk adjustment
M51.A1 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
M51.A1 is named in 8 Medicare coverage policies — 2 listing it as supporting medical necessity, and 6 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A58865Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A58893Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A59374Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A59434Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
How M51.A1 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to M51.A1.
- Defect, defective›intervertebral annular fibrosis›lumbar›small
Related codes at this level
Codes that share M51.A. If M51.A1 is not quite right, the correct code is usually one of these.
- M51.A0Intervertebral annulus fibrosus defect, lumbar region, unspecified size
- M51.A2Intervertebral annulus fibrosus defect, large, lumbar region
- M51.A3Intervertebral annulus fibrosus defect, lumbosacral region, unspecified size
- M51.A4Intervertebral annulus fibrosus defect, small, lumbosacral region
- M51.A5Intervertebral annulus fibrosus defect, large, lumbosacral region
Questions about M51.A1
- Is M51.A1 a billable ICD-10-CM code?
- Yes. M51.A1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does M51.A1 sit in the tabular list?
- Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Other dorsopathies (M50-M54).