M99Header code — not billable
Biomechanical lesions, not elsewhere classified
- Chapter
- 13. Diseases of the musculoskeletal system and connective tissue
- Category
- M99
- Effective date
- October 1, 2026
Related codes in category M99
M99.0Segmental and somatic dysfunctionM99.00Segmental and somatic dysfunction of head regionYesM99.01Segmental and somatic dysfunction of cervical regionYesM99.02Segmental and somatic dysfunction of thoracic regionYesM99.03Segmental and somatic dysfunction of lumbar regionYesM99.04Segmental and somatic dysfunction of sacral regionYesM99.05Segmental and somatic dysfunction of pelvic regionYesM99.06Segmental and somatic dysfunction of lower extremityYesM99.07Segmental and somatic dysfunction of upper extremityYesM99.08Segmental and somatic dysfunction of rib cageYesM99.09Segmental and somatic dysfunction of abdomen and oth regionsYesM99.1Subluxation complex (vertebral)
Frequently asked questions
What is ICD-10 code M99?
M99 is an ICD-10-CM diagnosis code for Biomechanical lesions, not elsewhere classified.
Is M99 a billable code?
No. M99 is a category/header code, not billable on its own — use one of its more specific child codes instead.
What ICD-10-CM chapter is M99 in?
M99 falls under Chapter 13: Diseases of the musculoskeletal system and connective tissue.
When did M99 become effective?
M99 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to M99?
M99 belongs to category M99, which includes 12 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.