ICD-10-CM · Multi-region

M99.06

M99.06 identifies segmental and somatic dysfunction localized to the lower extremity, classified under biomechanical lesions not elsewhere classified (M99) in ICD-10-CM Chapter 13.

Verified May 8, 2026 · 5 sources ↓

Status
Billable
Chapter
13
Related CPT
12
Region
Multi-region
Drawn from CDCICD10DataAAPCOpscCMS

Documentation tips

What should appear in the chart to support M99.06.

Source · Editorial brief grounded in 5 cited references ↓

  • Specify which lower extremity segment is affected (hip, knee, ankle, foot) and note laterality where clinically applicable.
  • Record objective somatic dysfunction findings: restricted range of motion, tissue texture abnormality, asymmetry, and tenderness (TART criteria).
  • Document that conservative or manipulative treatment was directed at the lower extremity to support medical necessity.
  • Note any prior treatment history and patient response to establish complexity and justify ongoing care.
  • If imaging was obtained, include findings in the note even if negative — this distinguishes somatic dysfunction from structural pathology and defends the M99.06 selection.

Related CPT procedures

Procedure codes commonly billed with M99.06. 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 M99.06 and adjacent codes.

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

  • Billing the non-billable parent code M99.0 instead of the specific child code M99.06 — claims will reject.
  • Using M99.06 when a definitive structural diagnosis (e.g., M16.11 primary osteoarthritis of right hip) has been established; the specific pathology code should be primary.
  • Omitting a secondary symptom or pain code on Medicare chiropractic claims — many MACs require it alongside M99.0x codes.
  • Applying M99.06 to spinal or pelvic dysfunction; use M99.03 (lumbar), M99.04 (sacral), or M99.05 (pelvic) for those regions.
  • Failing to code all affected regions when multiple segments are treated in one encounter — each applicable M99.0x code should be reported separately.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

M99.06 applies when a provider — typically a chiropractor or osteopathic physician — documents segmental or somatic dysfunction of the lower extremity (hip, thigh, knee, leg, ankle, foot). The code reflects restricted or altered motion, tissue texture changes, or asymmetry attributable to a biomechanical lesion rather than a structural pathology like fracture or osteoarthritis. It sits within the M99.0x family, which requires specificity by body region; the parent code M99.0 is non-billable and cannot be submitted on a claim.

In chiropractic and osteopathic manipulative therapy (OMT) billing, M99.06 is frequently the primary diagnosis when the lower extremity is the primary treatment region. For Medicare chiropractic claims, payers such as Novitas expect an M99.0x code listed first, followed by a supporting symptom or pain code as a secondary diagnosis. Confirm your MAC's LCD requirements before submitting.

Do not use M99.06 for a definitively diagnosed structural condition (e.g., hip OA, knee ligament tear). Once imaging or clinical workup establishes a specific pathology, report that definitive code as primary. M99.06 may remain as a secondary code if somatic dysfunction co-exists and is separately addressed.

Sibling codes

Other billable codes under M99.0 (laterality / anatomic variants).

Frequently asked questions

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

01Is M99.06 valid for Medicare chiropractic billing?
Yes. List M99.06 as the primary diagnosis and add a secondary pain or symptom code. Confirm your MAC's LCD — Novitas, for example, requires this pairing explicitly.
02Can M99.06 be billed alongside a structural diagnosis like hip osteoarthritis?
Yes, as a secondary code if somatic dysfunction of the lower extremity is separately documented and treated. The definitive structural diagnosis (e.g., M16.11) should be listed first.
03Does M99.06 require laterality?
No — the M99.0x family does not carry a laterality character. Document laterality in the clinical note, but the code itself does not differentiate right from left.
04What is the ICD-9 crosswalk for M99.06?
The approximate ICD-9 equivalent is 739.6 (nonallopathic lesion of lower extremity). This is a GEM approximate match, not an exact mapping.
05When should I use M99.05 (pelvic) versus M99.06 (lower extremity)?
Use M99.05 when the somatic dysfunction is localized to the pelvis or sacroiliac joint. Use M99.06 when the primary dysfunction involves the hip joint, thigh, knee, leg, ankle, or foot. Both may be reported together if both regions are treated.
06Can M99.06 be used by physical therapists?
The code is clinically applicable to any licensed provider who documents and treats segmental or somatic dysfunction of the lower extremity, including physical therapists, as long as the diagnosis is within their scope of practice under state law.
07Is there a more specific code if only the knee is affected?
No — M99.06 is the most specific available code for lower extremity somatic dysfunction within the M99 category. There is no knee-only subcode. Supplement with a specific knee diagnosis code if a structural condition is also documented.

Sources & references

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

  1. 01CDC ICD-10-CM Tabular List 2026 (effective Oct 1, 2025)
  2. 02
    icd10data.com
    https://www.icd10data.com/ICD10CM/Codes/M00-M99/M99-M99/M99-/M99.06
  3. 03
    aapc.com
    https://www.aapc.com/codes/icd-10-codes/M99.06
  4. 04
    opsc.org
    https://www.opsc.org/page/ICD-10
  5. 05
    cms.gov
    https://www.cms.gov/Medicare/Coding/ICD10/Downloads/2019-ICD10-Coding-Guidelines-.pdf

Mira AI Scribe

Mira captures the TART findings (tissue texture, asymmetry, restriction, tenderness) documented during the lower extremity exam, the specific segment treated, laterality, and any prior conservative care history. This prevents downcoding to the non-billable M99.0 parent, satisfies MAC medical-necessity requirements, and supports multi-code reporting when additional regions are addressed in the same visit.

See how Mira captures M99.06 documentation

Related ICD-10 codes

Ready?

Ready to transform your orthopedic practice?

See how orthopedic practices are running documentation, billing, and operations on a single voice-first platform.

Get started for free