2027 ICD-10-CM Diagnosis Code L98.A124Non-pressure chronic ulcer of left upper arm with necrosis of bone
ICD-10-CM Codes›L00–L99›L80-L99›L98
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 380
- 7th Character 4
- Chronic Condition
L98.A124 is a billable ICD-10-CM diagnosis code for non-pressure chronic ulcer of left upper arm with necrosis of bone. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 573 through 575, 592 through 594. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 325 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Aseptic necrosis and osteonecrosis and Non-pressure ulcer of skin.
For Medicare Advantage risk adjustment, L98.A124 maps to CMS-HCC Category 380 (Chronic Ulcer of Skin, Except Pressure, Through to Bone or Muscle) under the V28 model, adding a risk factor of about 1.078 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
L98.A124 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to L98.A124: its own notes plus those printed at L98.A and Chapter 12. A note printed at a category, block or chapter applies to every code under it.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- lipomelanotic reticulosis (I89.8)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- viral warts (B07.-)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Bone Diseases
Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Code History & ChangesHistory
Replacement L98.A124 replaces the following previously assigned code(s):
- L98.494 - Non-prs chronic ulcer of skin of sites w necrosis of bone
Questions About L98.A124Overview
What is the ICD-10 code for non-pressure chronic ulcer of left upper arm with necrosis of bone?
The ICD-10-CM code for non-pressure chronic ulcer of left upper arm with necrosis of bone is L98.A124 (sometimes written as L98A124). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is L98.A124 (Non-pressure chronic ulcer of left upper arm) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report non-pressure chronic ulcer of left upper arm with necrosis of bone on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does L98.A124 group to?
When non-pressure chronic ulcer of left upper arm with necrosis of bone is the principal diagnosis on an inpatient stay, it groups to MS-DRG 592, 573, 574, 575, 593, 594, with relative weights from 0.7347 to 6.3547 depending on complications. Higher weights mean higher Medicare reimbursement.
Is L98.A124 a CC or MCC?
CMS lists L98.A124 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 325 closely related codes in its exclusion list.
What HCC is L98.A124?
L98.A124 (non-pressure chronic ulcer of left upper arm with necrosis of bone) maps to CMS-HCC Category 380 (Chronic Ulcer of Skin, Except Pressure, Through to Bone or Muscle), commonly written as HCC 380, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 311.
Does L98.A124 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, L98.A124 adds a risk adjustment factor of about 1.078 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.839 to 1.422 depending on the payment segment). A more severe related category (HCC 379) supersedes it when both are reported. See the full factor table on the HCC 380 category page.
