Familial chondrocalcinosis with no specific joint site documented — a hereditary crystal arthropathy characterized by calcium pyrophosphate dihydrate (CPPD) deposits in cartilage, assigned when the affected joint is not identified in the record.
Verified May 8, 2026 · 4 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 7
- Region
- Multi-region
Documentation tips
What should appear in the chart to support M11.10.
Source · Editorial brief grounded in 4 cited references ↓
- Record the specific joint(s) showing chondrocalcinosis on imaging — even one named joint moves the code from M11.10 to a billable site-specific child code with greater specificity.
- Document family history explicitly: note whether a first-degree relative has confirmed CPPD disease or a hereditary chondrocalcinosis syndrome to justify the M11.1x family over M11.2x.
- Include radiographic findings in the assessment — joint space narrowing, cartilage calcification, or chondrocalcinosis on X-ray or MRI supports medical necessity and distinguishes from incidental crystal deposits.
- If synovial fluid analysis is performed, record CPP crystal identification in the note; this supports the CPPD diagnosis and links directly to any joint aspiration CPT billed on the same date.
- When the patient has polyarticular involvement, list each affected joint by name so M11.19 (multiple sites) can replace M11.10, reducing audit exposure from an unspecified-site code.
Related CPT procedures
Procedure codes commonly billed with M11.10. Linking the right diagnosis to the right procedure is what establishes medical necessity.
Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis
Common coding pitfalls
The recurring mistakes coders make with M11.10 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Using M11.10 when a specific joint is documented in the note — imaging or exam findings that name the joint require a site-specific child code (e.g., M11.161 for right knee).
- Confusing M11.10 (familial) with M11.20 (other chondrocalcinosis, unspecified site) — the M11.1x family requires documented hereditary or familial etiology; absent that, M11.2x is correct.
- Billing the parent code M11.1 instead of M11.10 — M11.1 is non-billable; M11.10 is the required billable code when site is unspecified.
- Defaulting to M11.10 for polyarticular disease when M11.19 (multiple sites) is the more accurate and specific code if the note names more than one affected joint.
- Omitting a secondary metabolic code when chondrocalcinosis is attributed to an underlying disorder such as hyperparathyroidism — in those cases the metabolic condition (e.g., E83.5x) should also be coded.
Clinical context
Source · Editorial summary grounded in 4 cited references ↓
M11.10 applies when the provider documents a familial (hereditary) form of chondrocalcinosis but does not specify which joint is involved. Familial chondrocalcinosis is distinguished from other chondrocalcinosis subtypes (M11.2x) by its genetic basis — typically an autosomal dominant pattern — and from metabolic causes such as hyperparathyroidism or hemochromatosis, which carry their own codes. If the clinical note identifies the joint, step down to the site-specific code: M11.161/M11.162 for knee, M11.151/M11.152 for hip, M11.111/M11.112 for shoulder, and so on across the full M11.1x family.
In orthopedic practice, this code appears most often at initial evaluation before imaging confirms the exact joint(s) involved, or when multijoint disease is present but the provider's note doesn't explicitly catalog each site. If multiple joints are documented, consider M11.19 (familial chondrocalcinosis, multiple sites) rather than defaulting to M11.10. Reserve M11.10 strictly for genuinely unspecified-site encounters — payers and auditors recognize unspecified codes as lower-specificity claims and may request additional documentation.
Do not confuse M11.10 with M11.20 (other chondrocalcinosis, unspecified site). The M11.1x family requires documented or clearly implied familial/hereditary etiology — a positive family history in the chart, a genetic diagnosis, or a provider statement linking the condition to hereditary CPPD disease. Without that, M11.20 or M11.29x is the correct parent.
Sibling codes
Other billable codes under M11.1 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 4 cited references ↓
01When is M11.10 the right code versus M11.20?
02Can I use M11.10 if the patient has bilateral knee chondrocalcinosis documented on X-ray?
03Is M11.1 billable, or do I need M11.10?
04What documentation supports the 'familial' designation in M11.10?
05Should I code an underlying metabolic condition alongside M11.10?
06Does M11.10 require a 7th-character extension?
07What CPT codes commonly pair with M11.10 in an orthopedic setting?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CDC ICD-10-CM Tabular List 2026 (effective Oct 1, 2025)
- 02icd10data.comhttps://www.icd10data.com/ICD10CM/Codes/M00-M99/M05-M14/M11-/M11.10
- 03aapc.comhttps://www.aapc.com/codes/icd-10-codes/M11.1
- 04cms.govhttps://www.cms.gov/icd10m/FY2024-version41-fullcode-cms/fullcode_cms/P1516.html
Mira AI Scribe
Mira captures the provider's family history notation, the specific joint(s) called out on imaging, and any radiographic descriptors (cartilage calcification, chondrocalcinosis on X-ray) that appear during the encounter. That data populates the site-specific M11.1x child code automatically — preventing a default to M11.10 when a joint is named, which eliminates the unspecified-site audit flag and ensures the claim reflects the highest level of documented specificity.
See how Mira captures M11.10 documentation