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S66.811A vs S66.812A

S66.811A (Strain of other specified muscles, fascia and tendons at wrist and hand level, right hand, initial encounter) compared with S66.812A (Strain of other specified muscles, fascia and tendons at wrist and hand level, left hand, initial encounter), from the official CMS tabular data. S66.811A and S66.812A code the same condition on opposite sides. MedCoder-derived

Relationship

Review

Laterality relationship

S66.811A
Right
Strain of other specified muscles, fascia and tendons at wrist and hand level, right hand, initial encounter
S66.812A
Left
Strain of other specified muscles, fascia and tendons at wrist and hand level, left hand, initial encounter

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. S66.811A and S66.812A 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

S66.811AStrain of other specified muscles, fascia and tendons at wrist and hand level, right hand, initial encounterS66.812AStrain of other specified muscles, fascia and tendons at wrist and hand level, left hand, initial encounter
Billing statusBillableBillable
ClassificationS00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)
DefinitionStrain of other specified muscles, fascia and tendons at wrist and hand level, right hand, initial encounter is a billable ICD-10-CM diagnosis code (S66.811A).Strain of other specified muscles, fascia and tendons at wrist and hand level, left hand, initial encounter is a billable ICD-10-CM diagnosis code (S66.812A).
7th characterThe appropriate 7th character is to be added to each code from category S66The appropriate 7th character is to be added to each code from category S66

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