L05.91 — Pilonidal cyst without abscess
L05.91 is a billable, specific ICD-10-CM code for pilonidal cyst without abscess. It is valid for submission on a claim.
Excludes2 — not included here, but may coexist
The excluded condition is not part of this code, but a patient can have both. You may code both.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Pilonidal dimple
- Postanal dimple
- Pilonidal cyst NOS
Risk adjustment
L05.91 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
L05.91 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56766Billing and Coding: Incision and Drainage (I&D) of Abscess of Skin, Subcutaneous and Accessory Structures
How L05.91 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 L05.91.
- Cyst›pilonidal(infected) (rectum)
Related codes at this level
Codes that share L05.9. If L05.91 is not quite right, the correct code is usually one of these.
Questions about L05.91
- Is L05.91 a billable ICD-10-CM code?
- Yes. L05.91 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does L05.91 sit in the tabular list?
- Diseases of the skin and subcutaneous tissue (L00-L99), in the block Infections of the skin and subcutaneous tissue (L00-L08).