ICD-10-CM · Spine

M06.38

M06.38 identifies a rheumatoid nodule located at the vertebrae, classified under other rheumatoid arthritis without rheumatoid factor involvement as the primary driver.

Verified May 8, 2026 · 5 sources ↓

Status: Billable
Chapter: 13
Related CPT: 8
Region: Spine

Drawn from CDCICD10DataRheumatologyadvisorAAPCCMS

Documentation tips

What should appear in the chart to support M06.38.

Source · Editorial brief grounded in 5 cited references ↓

Explicitly name the vertebrae as the nodule site — 'rheumatoid nodule at the cervical/thoracic/lumbar vertebrae' — rather than generic spinal involvement.
Document whether rheumatoid factor is positive or negative; this determines whether M05.x or M06.x is the appropriate parent category.
Record imaging findings (MRI or CT) confirming the vertebral nodule location and size to support medical necessity for advanced imaging CPTs.
Note any functional or neurological impact of the vertebral nodule, as these comorbidities influence MS-DRG tier assignment (MCC vs. CC vs. neither).
If nodules are present at additional anatomic sites in the same encounter, document each site explicitly so the coder can evaluate M06.38 plus a peripheral site code versus M06.39 (multiple sites).

Related CPT procedures

Procedure codes commonly billed with M06.38. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

72148 $191.72

Non-contrast MRI of the lumbar spine used to evaluate disc pathology, spinal stenosis, nerve root compression, and other structural abnormalities without administration of contrast material.

72141 $190.72

MRI of the cervical spinal canal and its contents performed without contrast material.

72158 $318.31

MRI of the lumbar spinal canal and its contents performed first without contrast, then repeated after contrast administration for enhanced visualization.

99213 $95.19

Established patient office or outpatient visit requiring 20–29 minutes of total time or low-complexity medical decision-making.

99214 $135.61

Office visit for an established patient requiring moderate-complexity medical decision making (MDM), or 30–39 minutes of total provider time on the date of service.

99215 $192.39

Highest-level office or outpatient E/M visit for an established patient, qualifying via high-complexity medical decision making or 40–54 minutes of total provider time on the date of service.

20610 $68.81

Aspiration and/or injection of a major joint or bursa (shoulder, hip, knee, or subacromial bursa) performed without ultrasound guidance.

72020 $23.71

Single-view radiologic examination of the spine at a specified level.

Common coding pitfalls

The recurring mistakes coders make with M06.38 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

Defaulting to M06.30 (unspecified site) when the vertebral location is clearly documented — M06.38 is the correct billable code when the spine is specified.
Confusing M06.38 (rheumatoid nodule, vertebrae) with M06.28 (rheumatoid bursitis, vertebrae) — nodule and bursitis are distinct subcategories under M06 and are not interchangeable.
Using M06.39 (multiple sites) when only the vertebrae are documented — reserve multiple-sites codes for encounters where nodules at two or more distinct anatomic regions are explicitly noted.
Failing to code underlying rheumatoid arthritis diagnosis separately when the clinical encounter addresses both the RA and the vertebral nodule as distinct problems — M06.38 does not capture the arthritis itself.
Overlooking comorbidities that would shift the MS-DRG from 547 (no CC/MCC) to 546 or 545, which requires all relevant diagnoses to be coded and sequenced correctly.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

M06.38 is used when a patient with rheumatoid arthritis presents with a nodular lesion specifically at the vertebral column. Rheumatoid nodules at the spine are uncommon compared to peripheral sites such as the elbow or hand, but their vertebral location warrants precise site-specific coding rather than defaulting to M06.30 (unspecified site) or M06.39 (multiple sites).

This code sits within the M06.3x subcategory, which covers rheumatoid nodules by anatomic site. Unlike the M05.x codes, the M06.3x family does not presuppose seropositivity — M06.38 applies regardless of rheumatoid factor status. If nodules are also present at peripheral joints in the same encounter, consider whether M06.39 (multiple sites) better captures the full clinical picture, or whether separate site-specific codes are clinically warranted and supported by documentation.

M06.38 maps to MS-DRG v43.0 groups 545–547 (Connective tissue disorders with MCC, CC, or without CC/MCC), so the presence of complicating comorbidities documented in the same encounter directly affects DRG assignment and reimbursement tier. Ensure all relevant comorbidities are coded to maximize appropriate DRG capture.

Sibling codes

Other billable codes under M06.3 (laterality / anatomic variants).

M06.39

Rheumatoid nodule, multiple sites

M06.30

Rheumatoid nodule, unspecified site

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01Does M06.38 require rheumatoid factor to be negative?

No. The M06.3x subcategory does not specify serostatus. M06.38 applies whether RF is positive, negative, or not yet tested — it captures the nodule at the vertebral site regardless of factor status.

02When should I use M06.39 (multiple sites) instead of M06.38?

Use M06.39 only when rheumatoid nodules are documented at two or more distinct anatomic regions in the same encounter. If the vertebrae are the sole documented site, M06.38 is correct.

03Can M06.38 be the principal diagnosis, or should the underlying RA code lead?

Sequencing depends on what drove the encounter. If the visit is specifically for evaluation or management of the vertebral nodule, M06.38 can lead. If the RA itself is the primary reason and the nodule is incidental, sequence the RA code first and M06.38 as an additional diagnosis.

04What is the difference between M06.28 and M06.38?

M06.28 is rheumatoid bursitis at the vertebrae; M06.38 is a rheumatoid nodule at the vertebrae. They represent distinct pathological processes under different M06 subcategories and must not be used interchangeably.

05How does M06.38 affect DRG assignment?

M06.38 groups to MS-DRG v43.0 codes 545, 546, or 547 (connective tissue disorders). The tier — with MCC, with CC, or without CC/MCC — is determined by the full set of coded diagnoses for the encounter, so complete comorbidity coding is essential.

06Is a specific vertebral level (cervical, thoracic, lumbar) required for M06.38?

The ICD-10-CM classification does not subdivide M06.38 by vertebral level — the single code covers all spinal regions. However, documenting the specific level supports medical necessity for imaging and any interventional procedures billed alongside it.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the vertebral location of the rheumatoid nodule from clinical notes and imaging reports, along with rheumatoid factor status, any neurological or functional deficits caused by the lesion, and a list of active comorbidities. This specificity prevents a drop to the unspecified-site code M06.30 and ensures comorbidities are coded to the correct MS-DRG tier rather than defaulting to the no-CC/MCC group.

See how Mira captures M06.38 documentation