M87.078 (Idiopathic aseptic necrosis of left toe(s)) compared with M87.079 (Idiopathic aseptic necrosis of unspecified toe(s)), from the official CMS tabular data. M87.078 and M87.079 code the same condition on opposite sides. MedCoder-derived
Same condition; these differ only in which side is documented.
These codes share a category and title and differ only in the side affected. The documentation decides which applies, and a bilateral code is reported only where the code set provides one.
Source: ICD-10-CM tabular list (laterality variant derived from the code title)
Same condition, opposite side. M87.078 and M87.079 name the same condition on opposite sides of the body.
Same category and title, differing only in which side is affected — the documentation decides which one applies, and a bilateral code is reported only where the code set provides one.
| M87.078Idiopathic aseptic necrosis of left toe(s) | M87.079Idiopathic aseptic necrosis of unspecified toe(s) | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) |
| Definition | Idiopathic aseptic necrosis of left toe(s) is a billable ICD-10-CM diagnosis code (M87.078). | Idiopathic aseptic necrosis of unspecified toe(s) is a billable ICD-10-CM diagnosis code (M87.079). |
| Includes | avascular necrosis of bone | avascular necrosis of bone |
| Use additional code | code to identify major osseous defect, if applicable (M89.7-) | code to identify major osseous defect, if applicable (M89.7-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources