M99.68 identifies narrowing of the intervertebral foramina of the rib cage caused by bony (osseous) changes or joint subluxation — a biomechanical lesion classified under Chapter 13 of ICD-10-CM.
Verified May 8, 2026 · 6 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 5
- Region
- Spine
Documentation tips
What should appear in the chart to support M99.68.
Source · Editorial brief grounded in 6 cited references ↓
- Specify the rib cage / thoracic costovertebral region explicitly — generic 'thoracic spine' language may not clearly distinguish rib cage foraminal involvement from thoracic vertebral canal stenosis.
- Document the mechanism of stenosis as osseous (e.g., osteophytes, bony hypertrophy) or subluxation-based; this separates M99.68 from connective tissue/disc stenosis (M99.78) and from neural canal stenosis (M99.58).
- Record any imaging findings (CT, MRI, or plain film) showing foraminal narrowing, osteophyte formation, or costovertebral joint positional change to support medical necessity on audit.
- For Medicare chiropractic billing, document the level(s) of subluxation and confirm the diagnosis meets the 'subluxation' definition required by the applicable LCD — M99.68 alone is insufficient without that clinical narrative.
- Note laterality of symptoms (left vs. right rib cage) in the clinical note even though M99.68 does not carry a laterality character; payers may request it for medical review.
Related CPT procedures
Procedure codes commonly billed with M99.68. 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 M99.68 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Confusing M99.68 (osseous/subluxation stenosis of foramina, rib cage) with M99.58 (intervertebral disc stenosis of neural canal, rib cage) — these are anatomically and mechanistically distinct; the distinction must be supported by documentation.
- Using M99.68 when the underlying stenosis is caused by disc or connective tissue pathology — those cases belong to M99.78 (connective tissue and disc stenosis of intervertebral foramina, rib cage).
- Defaulting to the unspecified thoracic region code (M99.62) when the documented site is the rib cage — M99.62 is for the thoracic vertebral region specifically, while M99.68 is reserved for the rib cage.
- Omitting a secondary pain or symptom code on Medicare chiropractic claims, which Novitas and other MACs require alongside the M99.0x or M99.6x biomechanical lesion code.
Clinical context
Source · Editorial summary grounded in 6 cited references ↓
M99.68 falls under the M99.6x subcategory (osseous and subluxation stenosis of intervertebral foramina) and is specific to the rib cage region. Use it when documentation supports foraminal narrowing at the costovertebral or costotransverse joints driven by bony hypertrophy, osteophyte formation, or positional subluxation — not by disc material or connective tissue (those map to M99.7x) and not by soft tissue alone.
This code appears most often in chiropractic, osteopathic, and physiatry billing contexts where the clinician documents a biomechanical basis for thoracic or rib cage nerve impingement. It is billable and maps to MS-DRG MDC 08 (Diseases and Disorders of the Musculoskeletal System). Do not use it as a standalone functional descriptor when a more specific structural diagnosis — such as a thoracic disc herniation or thoracic spondylosis with radiculopathy — is documented and better represents the pathology.
If the stenosis involves multiple spinal regions, code each region separately; there is no 'multiple sites' code within the M99.6x subcategory. For Medicare chiropractic claims, pair M99.68 with a subluxation-supporting code per applicable LCD requirements and include a relevant pain code as a secondary diagnosis.
Sibling codes
Other billable codes under M99.6 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 6 cited references ↓
01What is the difference between M99.68 and M99.62?
02When should I use M99.78 instead of M99.68?
03Is M99.68 valid for Medicare chiropractic billing?
04Does M99.68 require a 7th character?
05Can M99.68 be used alongside a thoracic radiculopathy code?
06What ICD-9-CM code did M99.68 replace?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CDC ICD-10-CM Tabular List 2026 (effective October 1, 2025)
- 02icd10data.comhttps://www.icd10data.com/ICD10CM/Codes/M00-M99/M99-M99/M99-/M99.68
- 03cms.govhttps://www.cms.gov/icd10m/FY2024-version41-fullcode-cms/fullcode_cms/P0555.html
- 04aapc.comhttps://www.aapc.com/codes/icd-10-codes/M99.68
- 05cms.govhttps://www.cms.gov/files/document/fy-2025-icd-10-cm-coding-guidelines.pdf
- 06opsc.orghttps://www.opsc.org/page/ICD-10
Mira AI Scribe
Mira's AI scribe captures the clinician's identification of the affected region (rib cage), the structural basis for foraminal narrowing (osseous changes or subluxation versus disc or connective tissue), any imaging findings supporting foraminal compromise, and the patient's symptom laterality. Capturing this detail prevents downcoding to a non-specific thoracic stenosis code and preempts payer requests for clinical documentation on audit.
See how Mira captures M99.68 documentation