S66 is a non-billable/non-specific diagnosis code from the 2025 ICD-10-CM used to classify the following condition: Injury of muscle, fascia and tendon at wrist and hand level.
Code also
Any associated open wound (S61.-)
Type 2 excludes
Sprain of joints and ligaments of wrist and hand (S63.-)
Seventh character note
The appropriate 7th character is to be added to each code from category S66
Seventh character extensions
A: initial encounter
D: subsequent encounter
S: sequela
Codes
S66.0
Injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level
S66.1
Injury of flexor muscle, fascia and tendon of other and unspecified finger at wrist and hand level
S66.2
Injury of extensor muscle, fascia and tendon of thumb at wrist and hand level
S66.3
Injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level
S66.4
Injury of intrinsic muscle, fascia and tendon of thumb at wrist and hand level
S66.5
Injury of intrinsic muscle, fascia and tendon of other and unspecified finger at wrist and hand level
S66.8
Injury of other specified muscles, fascia and tendons at wrist and hand level
S66.9
Injury of unspecified muscle, fascia and tendon at wrist and hand level
Versions
2025
No changes
2024
No changes
2023
No changes
2022
No changes
2021
No changes
2020
No changes
2019
No changes
2018
No changes
2017
No changes
2016
New code