R22.40 ICD-10-CM Code: Localized swelling, mass and lump, unspecified lower limb
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Coding at a Glance
- Tabular directives
- 1 inclusion term · 5 Excludes1 · 1 Excludes2
Inpatient Payment Groups (MS-DRG)
Potential MS-DRG participation — not a DRG assignment.
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.
- MS-DRG 606 — MINOR SKIN DISORDERS WITH MCC (MDC 09)
- MS-DRG 607 — MINOR SKIN DISORDERS WITHOUT MCC (MDC 09)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for R22.40 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Notes without a marker are published on R22.40 itself; “inherited from” names the category or block whose note applies here.
Includes
Conditions the official ICD-10-CM tabular list includes under this code.
- subcutaneous nodules (localized)(superficial)
Source: inherited from R22
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- abnormal findings on diagnostic imaging (R90-R93) Compare R22.40 vs R90 →
- edema (R60.-) Compare R22.40 vs R60 →
- enlarged lymph nodes (R59.-) Compare R22.40 vs R59 →
- localized adiposity (E65) Compare R22.40 vs E65 →
- swelling of joint (M25.4-) Compare R22.40 vs M25.4 →
Source: inherited from R22
Coder workflow for R22.40
MedCoder structured workflow — derived from this code’s own official record
Before you code R22.40
- Check whether an established diagnosis that explains this sign or symptom is documented. If one is, review whether the documented diagnosis changes the coding pathway: a symptom that is integral to a confirmed diagnosis is not reported separately, while one not routinely associated with it may be. Signs and symptoms are reported when no definitive diagnosis is established (Guidelines I.B.4, I.B.5, I.B.6, I.C.18.b).
- Unspecified does not mean incorrect. When the record gives no greater specificity, R22.40 may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).
See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →
- Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: unspecified). The unspecified-side code applies only when the record states no side. Laterality is assigned from the documented side; where a bilateral code exists and both sides are documented, it is used instead of two unilateral codes (Guidelines I.B.13).
ReviewR22.41 · right, R22.42 · left
- Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with R22.40. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
Choose the right path
- Is an established diagnosis that explains this sign or symptom documented?
Yes → Review whether the documented diagnosis changes the coding pathway: a symptom integral to it is not reported separately.
No → Continue — the sign or symptom code stands when no definitive diagnosis is established. - Does the record document the detail a more specific sibling code needs?
Yes → Review the specific siblings in this subcategory.
No → Continue — R22.40 is appropriate when the documentation goes no further. - Does the documentation support a condition named in R22.40’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue. - Is the side documented?
Yes → Select the code for the documented side (or the bilateral code when both sides are documented and one exists).
No → Use the unspecified-side code only when the record states no side; a query is the alternative.ReviewR22.41 · right, R22.42 · left
Consider R22.40. Then confirm the code is valid for the date of service in the Verify section.
Documentation check
- The provider’s diagnostic statement
- Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
- Laterality
- Right, left or bilateral as documented; unspecified only when the record states no side (Guidelines I.B.13).
- Any detail beyond this code’s title
- What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.
Official instructions as workflow
Excludes1 — check before selecting R22.40(5 notes)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with R22.40: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of R22.40(1 note)
Coding workflow: The conditions named in this note are not included in R22.40. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
See the official tabular notes · Guidelines I.A.12.b
Coding decision scenarios
Pattern scenarios for this code’s structure — decision rules, not clinical cases
Documentation: The sign or symptom is documented, and the same record establishes a diagnosis that routinely includes it.
Coding question: Is R22.40 reported in addition to the diagnosis?
Path: Review the documented diagnosis and whether the classification treats this finding as integral to it.
Reason: Signs and symptoms integral to a confirmed diagnosis are not coded separately; those not routinely associated with it may be reported when present (Guidelines I.B.5, I.B.6, I.C.18.b).
Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.
Coding question: Is a more specific sibling code supportable?
Path: Review the specific siblings in this subcategory and what each requires the record to state.
Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).
Documentation: Both the condition R22.40 describes and a condition named in its Excludes1 note are documented for the same encounter.
Coding question: Can both codes be reported?
Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.
Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).
Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Verify Before Coding
- No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Relationships & Classification
MedCoder structured relationships — computed from published CMS and AHRQ datasets
MS-DRG Grouper Relationships (FY2026)
Potential MS-DRG participation — not a DRG assignment.
FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.
Named in the grouper logic of 2 MS-DRGs: DRG 606 (MDC 09), DRG 607 (MDC 09).
From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.
Clinical classification (AHRQ CCSR):SYM014 — Skin/Subcutaneous signs and symptoms (default).
Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.
Related Codes
Same condition, opposite side
Same category and title, differing only in which side of the body is affected.
R22.41 — Localized swelling, mass and lump, right lower limb (right)Compare R22.40 vs R22.41 →, R22.42 — Localized swelling, mass and lump, left lower limb (left)Compare R22.40 vs R22.42 →
Same clinical category (CCSR)
AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Skin/Subcutaneous signs and symptoms).
R20.8 — Other disturbances of skin sensation, R20.9 — Unspecified disturbances of skin sensation, R21 — Rash and other nonspecific skin eruption, R22.0 — Localized swelling, mass and lump, head, R22.1 — Localized swelling, mass and lump, neck, R22.2 — Localized swelling, mass and lump, trunk, R22.30 — Localized swelling, mass and lump, unspecified upper limb, R22.31 — Localized swelling, mass and lump, right upper limb, R22.32 — Localized swelling, mass and lump, left upper limb, R22.33 — Localized swelling, mass and lump, upper limb, bilateral, R22.41 — Localized swelling, mass and lump, right lower limb, R22.42 — Localized swelling, mass and lump, left lower limb, R22.43 — Localized swelling, mass and lump, lower limb, bilateral, R22.9 — Localized swelling, mass and lump, unspecified, R23.0 — Cyanosis, R23.1 — Pallor, R23.2 — Flushing, R23.3 — Spontaneous ecchymoses, R23.4 — Changes in skin texture, R23.8 — Other skin changes, +5 more
Same Index main term, other category
The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Mass”; these codes share that main term but sit in a different category of the Tabular List.
H93.8 — Other specified disorders of ear (ear), N28.89 — Other specified disorders of kidney and ureter (kidney), N63.0 — Unspecified lump in unspecified breast (breast), R16.0 — Hepatomegaly, not elsewhere classified (liver), R16.1 — Splenomegaly, not elsewhere classified (splenic), R19.00 — Intra-abdominal and pelvic swelling, mass and lump, unspecified site (abdominal), R19.01 — Right upper quadrant abdominal swelling, mass and lump (abdominal, right upper quadrant), R19.02 — Left upper quadrant abdominal swelling, mass and lump (abdominal, left upper quadrant), R19.03 — Right lower quadrant abdominal swelling, mass and lump (abdominal, right lower quadrant), R19.04 — Left lower quadrant abdominal swelling, mass and lump (abdominal, left lower quadrant), R19.05 — Periumbilic swelling, mass or lump (abdominal, periumbilic), R19.06 — Epigastric swelling, mass or lump (abdominal, epigastric), R19.07 — Generalized intra-abdominal and pelvic swelling, mass and lump (abdominal, generalized), R19.09 — Other intra-abdominal and pelvic swelling, mass and lump (umbilical), R91.8 — Other nonspecific abnormal finding of lung field (lung)
Contextual Map
Every relationship of R22.40 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Hierarchy
- R00-R99 — Chapter 18: Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) (R00-R99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R20-R23 — Symptoms and signs involving the skin and subcutaneous tissue[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Clinical classification (CCSR)
- SYM014 — Skin/Subcutaneous signs and symptoms[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
MS-DRG Grouper
- DRG 606 — MINOR SKIN DISORDERS WITH MCC[MS-DRG]: “MINOR SKIN DISORDERS WITH MCC (MDC 09)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 607 — MINOR SKIN DISORDERS WITHOUT MCC[MS-DRG]: “MINOR SKIN DISORDERS WITHOUT MCC (MDC 09)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
MDC crossing
- MDC 09 — Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast[MDC crossing]: “Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 7,376 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026
Nearest codes (14)
- R22 — Localized swelling, mass and lump of skin and subcutaneous tissue[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.0 — Localized swelling, mass and lump, head[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.1 — Localized swelling, mass and lump, neck[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.2 — Localized swelling, mass and lump, trunk[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.3 — Localized swelling, mass and lump, upper limb[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.30 — Localized swelling, mass and lump, unspecified upper limb[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.31 — Localized swelling, mass and lump, right upper limb[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- R22.32 — Localized swelling, mass and lump, left upper limb[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- and 6 more
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Sources for this page
Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.
- Code, title, tabular notes and index terms Official source data
- CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
- Inpatient payment groups Official source data
- CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
- Change history and date-of-service validity Official source data
- CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
- Comparisons, relationships and the contextual map MedCoder structured relationship
- Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
- Summary and FAQ answers MedCoder explanation
- Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
Cite this page
Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.
MedCoder.ai. "R22.40 — Localized swelling, mass and lump, unspecified lower limb." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/r22.40-localized-swelling-mass-and-lump-unspecified-lower-limb
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionLocalized swelling, mass and lump, unspecified lower limb
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to R22.40 in its code family, with their registry titles.
- R22.3 — Localized swelling, mass and lump, upper limb
- R22.30 — Localized swelling, mass and lump, unspecified upper limb
- R22.31 — Localized swelling, mass and lump, right upper limb
- R22.32 — Localized swelling, mass and lump, left upper limb
- R22.33 — Localized swelling, mass and lump, upper limb, bilateral
- R22.4 — Localized swelling, mass and lump, lower limb
- R22.41 — Localized swelling, mass and lump, right lower limb
- R22.42 — Localized swelling, mass and lump, left lower limb
- R22.43 — Localized swelling, mass and lump, lower limb, bilateral
- R22.9 — Localized swelling, mass and lump, unspecified