Biomechanical lesions, not elsewhere classified (M99) ICD-10-CM
The M99 code range covers biomechanical lesions, not elsewhere classified with 101 ICD-10-CM diagnosis codes. 91 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
- This category should not be used if the condition can be classified elsewhere.
Codes in the M99 Range 101 codes · 91 billable
- M99 Biomechanical lesions, not elsewhere classifiedNon-billable
- M99.0 Segmental and somatic dysfunctionNon-billable
- M99.00 Segmental and somatic dysfunction of head region
- M99.01 Segmental and somatic dysfunction of cervical region
- M99.02 Segmental and somatic dysfunction of thoracic region
- M99.03 Segmental and somatic dysfunction of lumbar region
- M99.04 Segmental and somatic dysfunction of sacral region
- M99.05 Segmental and somatic dysfunction of pelvic region
- M99.06 Segmental and somatic dysfunction of lower extremity
- M99.07 Segmental and somatic dysfunction of upper extremity
- M99.08 Segmental and somatic dysfunction of rib cage
- M99.09 Segmental and somatic dysfunction of abdomen and other regions
- M99.1 Subluxation complex (vertebral)Non-billable
- M99.10 Subluxation complex (vertebral) of head region
- M99.11 Subluxation complex (vertebral) of cervical region
- M99.12 Subluxation complex (vertebral) of thoracic region
- M99.13 Subluxation complex (vertebral) of lumbar region
- M99.14 Subluxation complex (vertebral) of sacral region
- M99.15 Subluxation complex (vertebral) of pelvic region
- M99.16 Subluxation complex (vertebral) of lower extremity
- M99.17 Subluxation complex (vertebral) of upper extremity
- M99.18 Subluxation complex (vertebral) of rib cage
- M99.19 Subluxation complex (vertebral) of abdomen and other regions
- M99.2 Subluxation stenosis of neural canalNon-billable
- M99.20 Subluxation stenosis of neural canal of head region
- M99.21 Subluxation stenosis of neural canal of cervical region
- M99.22 Subluxation stenosis of neural canal of thoracic region
- M99.23 Subluxation stenosis of neural canal of lumbar region
- M99.24 Subluxation stenosis of neural canal of sacral region
- M99.25 Subluxation stenosis of neural canal of pelvic region
- M99.26 Subluxation stenosis of neural canal of lower extremity
- M99.27 Subluxation stenosis of neural canal of upper extremity
- M99.28 Subluxation stenosis of neural canal of rib cage
- M99.29 Subluxation stenosis of neural canal of abdomen and other regions
- M99.3 Osseous stenosis of neural canalNon-billable
- M99.30 Osseous stenosis of neural canal of head region
- M99.31 Osseous stenosis of neural canal of cervical region
- M99.32 Osseous stenosis of neural canal of thoracic region
- M99.33 Osseous stenosis of neural canal of lumbar region
- M99.34 Osseous stenosis of neural canal of sacral region
- M99.35 Osseous stenosis of neural canal of pelvic region
- M99.36 Osseous stenosis of neural canal of lower extremity
- M99.37 Osseous stenosis of neural canal of upper extremity
- M99.38 Osseous stenosis of neural canal of rib cage
- M99.39 Osseous stenosis of neural canal of abdomen and other regions
- M99.4 Connective tissue stenosis of neural canalNon-billable
- M99.40 Connective tissue stenosis of neural canal of head region
- M99.41 Connective tissue stenosis of neural canal of cervical region
- M99.42 Connective tissue stenosis of neural canal of thoracic region
- M99.43 Connective tissue stenosis of neural canal of lumbar region
- M99.44 Connective tissue stenosis of neural canal of sacral region
- M99.45 Connective tissue stenosis of neural canal of pelvic region
- M99.46 Connective tissue stenosis of neural canal of lower extremity
- M99.47 Connective tissue stenosis of neural canal of upper extremity
- M99.48 Connective tissue stenosis of neural canal of rib cage
- M99.49 Connective tissue stenosis of neural canal of abdomen and other regions
- M99.5 Intervertebral disc stenosis of neural canalNon-billable
- M99.50 Intervertebral disc stenosis of neural canal of head region
- M99.51 Intervertebral disc stenosis of neural canal of cervical region
- M99.52 Intervertebral disc stenosis of neural canal of thoracic region
- M99.53 Intervertebral disc stenosis of neural canal of lumbar region
- M99.54 Intervertebral disc stenosis of neural canal of sacral region
- M99.55 Intervertebral disc stenosis of neural canal of pelvic region
- M99.56 Intervertebral disc stenosis of neural canal of lower extremity
- M99.57 Intervertebral disc stenosis of neural canal of upper extremity
- M99.58 Intervertebral disc stenosis of neural canal of rib cage
- M99.59 Intervertebral disc stenosis of neural canal of abdomen and other regions
- M99.6 Osseous and subluxation stenosis of intervertebral foraminaNon-billable
- M99.60 Osseous and subluxation stenosis of intervertebral foramina of head region
- M99.61 Osseous and subluxation stenosis of intervertebral foramina of cervical region
- M99.62 Osseous and subluxation stenosis of intervertebral foramina of thoracic region
- M99.63 Osseous and subluxation stenosis of intervertebral foramina of lumbar region
- M99.64 Osseous and subluxation stenosis of intervertebral foramina of sacral region
- M99.65 Osseous and subluxation stenosis of intervertebral foramina of pelvic region
- M99.66 Osseous and subluxation stenosis of intervertebral foramina of lower extremity
- M99.67 Osseous and subluxation stenosis of intervertebral foramina of upper extremity
- M99.68 Osseous and subluxation stenosis of intervertebral foramina of rib cage
- M99.69 Osseous and subluxation stenosis of intervertebral foramina of abdomen and other regions
- M99.7 Connective tissue and disc stenosis of intervertebral foraminaNon-billable
- M99.70 Connective tissue and disc stenosis of intervertebral foramina of head region
- M99.71 Connective tissue and disc stenosis of intervertebral foramina of cervical region
- M99.72 Connective tissue and disc stenosis of intervertebral foramina of thoracic region
- M99.73 Connective tissue and disc stenosis of intervertebral foramina of lumbar region
- M99.74 Connective tissue and disc stenosis of intervertebral foramina of sacral region
- M99.75 Connective tissue and disc stenosis of intervertebral foramina of pelvic region
- M99.76 Connective tissue and disc stenosis of intervertebral foramina of lower extremity
- M99.77 Connective tissue and disc stenosis of intervertebral foramina of upper extremity
- M99.78 Connective tissue and disc stenosis of intervertebral foramina of rib cage
- M99.79 Connective tissue and disc stenosis of intervertebral foramina of abdomen and other regions
- M99.8 Other biomechanical lesionsNon-billable
- M99.80 Other biomechanical lesions of head region
- M99.81 Other biomechanical lesions of cervical region
- M99.82 Other biomechanical lesions of thoracic region
- M99.83 Other biomechanical lesions of lumbar region
- M99.84 Other biomechanical lesions of sacral region
- M99.85 Other biomechanical lesions of pelvic region
- M99.86 Other biomechanical lesions of lower extremity
- M99.87 Other biomechanical lesions of upper extremity
- M99.88 Other biomechanical lesions of rib cage
- M99.89 Other biomechanical lesions of abdomen and other regions
- M99.9 Biomechanical lesion, unspecified
About the M99 Code Range
ICD-10 code range M99 is used to classify various biomechanical lesions, focusing on segmental and somatic dysfunctions, subluxation complexes, and stenosis affecting different body regions. This range specifically addresses conditions where structural or functional abnormalities in the spine, joints, or related tissues are not elsewhere classified.
The codes cover segmental and somatic dysfunction such as issues in the head (e.g., somatic dysfunction of the cranium and sphenobasilar synchondrosis), cervical spine (including cervical segmental dysfunction or neck pain), thoracic, lumbar (including lumbar segmental dysfunction and psoas syndrome), sacral, pelvic, and extremities. For example, M99.01 identifies cervical region dysfunction linked to terms like "Pain in cervical spine" and "Cervical somatic dysfunction." The range also includes the subluxation complex (vertebral) codes (M99.1x), helpful for coders identifying vertebral misalignments such as "Subluxation complex of cervical vertebra" (M99.11). Additionally, stenosis codes (M99.2 to M99.7) specify narrowing of neural canals due to subluxation, osseous, connective tissue, or intervertebral disc causes across multiple regions, assisting with precise documentation. For example, M99.61 denotes cervical intervertebral foramina stenosis by osseous and subluxation. The other biomechanical lesions codes (M99.8x) classify less specific structural issues in various body areas. Lastly, M99.9 captures unspecified biomechanical lesions, supporting cases where a detailed diagnosis is not available. This range is vital for detailing complex musculoskeletal conditions related to structural dysfunction and nerve canal narrowing, aiding accurate diagnosis and treatment planning.
Questions About This Page
How many billable codes are in the M99 range?
Of the 101 codes in this range, 91 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the M99 range classify?
The range classifies biomechanical lesions, not elsewhere classified. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
