ICD-10-CM 2027 diagnosis code
A66.6Bone and joint lesions of yaws
A66.6 is a valid, billable ICD-10-CM code for bone and joint lesions of yaws. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Looking up by condition? See ICD-10 code for Henpue, ICD-10 code for Goundou.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About A66.6
A66.6 is the ICD-10-CM diagnosis code for bone and joint lesions of yaws. It belongs to category A66 (yaws), block A65-A69 (other spirochetal diseases) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within A66 (yaws), A66.6 is specifically for bone and joint lesions of yaws. Related codes cover initial lesions of yaws (A66.0), multiple papillomata and wet crab yaws (A66.1), other early skin lesions of yaws (A66.2), Hyperkeratosis of yaws (A66.3), Gummata and ulcers of yaws (A66.4), Gangosa (A66.5), other manifestations of yaws (A66.7), latent yaws (A66.8) and 1 more.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 548 (Septic Arthritis with MCC, relative weight 1.9519), DRG 549 (Septic Arthritis with CC, relative weight 1.1435) and DRG 550 (Septic Arthritis without CC/MCC, relative weight 0.8591), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 102.6 (bone and joint lesions due to yaws).
Coding notes
- Yaws ganglion
- Yaws goundou
- Yaws gumma, bone
- Yaws gummatous osteitis or periostitis
- Yaws hydrarthrosis
- Yaws osteitis
- Yaws periostitis (hypertrophic)
Notes that apply from higher levels
Instructions written at a parent level also apply to A66.6.
› From A66 Yaws
- bouba
- frambesia (tropica)
- pian
Broader instructions also apply from A65-A69 Other spirochetal diseases and Chapter 1: Certain infectious and parasitic diseases.
Alphabetic index entries
17 entriesTerms in the official ICD-10-CM index that lead to A66.6.
- Ganglion (compound) (diffuse) (joint) (tendon (sheath)) › of yaws (early) (late)
- Goundou
- Gumma (syphilitic) › bone › of yaws (late)
- Gumma (syphilitic) › yaws › bone
- Henpue, henpuye
- Hydrarthrosis › of yaws (early) (late)
- Osteitis › due to yaws
- Periostitis (albuminosa) (circumscribed) (diffuse) (infective) (monomelic) › yaws (hypertrophic) (early) (late)
- Yaws › bone lesions
- Yaws › ganglion
- Yaws › gumma, gummata › bone
- Yaws › gummatous › osteitis
- Yaws › gummatous › periostitis
- Yaws › hydrarthrosis
- Yaws › joint lesions
- Yaws › osteitis
- Yaws › periostitis (hypertrophic)
Codes whose notes reference A66.6
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 08 · Diseases and Disorders of the Musculoskeletal System and Connective Tissue
ICD-9-CM equivalent
Converter →- 102.6Bone and joint lesions due to yawsexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about A66.6
Is A66.6 billable?
- Yes. A66.6 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A66.6 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A66.6 as a principal diagnosis.
Is A66.6 a CC or MCC?
- No. A66.6 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does A66.6 group to?
- A66.6 is used in the MS-DRG v44.0 logic for MS-DRG 548 (Septic Arthritis with MCC), MS-DRG 549 (Septic Arthritis with CC) and MS-DRG 550 (Septic Arthritis without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for A66.6?
- The CMS General Equivalence Mappings map A66.6 to ICD-9-CM 102.6.