Skip to main content

M65.171 vs M65.179

M65.171 (Other infective (teno)synovitis, right ankle and foot) compared with M65.179 (Other infective (teno)synovitis, unspecified ankle and foot), from the official CMS tabular data. M65.171 and M65.179 code the same condition on opposite sides. MedCoder-derived

Relationship

Review

Laterality relationship

M65.171
Right
Other infective (teno)synovitis, right ankle and foot
M65.179
Unspecified
Other infective (teno)synovitis, unspecified ankle and foot

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)

Can these codes be reported together?

Same condition, opposite side. M65.171 and M65.179 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.

Side by side

M65.171Other infective (teno)synovitis, right ankle and footM65.179Other infective (teno)synovitis, unspecified ankle and foot
Billing statusBillableBillable
ClassificationM00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99)M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99)
DefinitionOther infective (teno)synovitis, right ankle and foot is a billable ICD-10-CM diagnosis code (M65.171).Other infective (teno)synovitis, unspecified ankle and foot is a billable ICD-10-CM diagnosis code (M65.179).

Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources