M99.9
Biomechanical lesion, unspecified
BillableComplete code, valid to report
M99.9 (also written M999) is a billable ICD-10-CM diagnosis code for biomechanical lesion, unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 91 codes in category M99 (Biomechanical lesions, not elsewhere classified). The Alphabetic Index lists it under 1 entry. Its coding notes include 10 Excludes2 entries.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (10 notes)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
- arthropathic psoriasis (L40.5-)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- compartment syndrome (traumatic) (T79.A-)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Notes
Inherited from M99 Biomechanical lesions, not elsewhere classified
- This category should not be used if the condition can be classified elsewhere.
Also from chapter/block level (1 note)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
- Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 1 entry