S56.3Injury of extensor or abductor muscles, fascia and tendons of thumb at forearm level

S56.3 is the ICD-10-CM diagnosis code for injury of extensor or abductor muscles, fascia and tendons of thumb at forearm level. It belongs to category S56 (injury of muscle, fascia and tendon at forearm level), block S50-S59 (injuries to the elbow and forearm) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.

Within S56 (injury of muscle, fascia and tendon at forearm level), S56.3 is specifically for injury of extensor or abductor muscles, fascia and tendons of thumb at forearm level. Related codes cover flexor muscle, fascia and tendon of thumb at forearm level (S56.0), flexor muscle, fascia and tendon of other and unspecified finger at forearm level (S56.1), other flexor muscle, fascia and tendon at forearm level (S56.2), extensor muscle, fascia and tendon of other and unspecified finger at forearm level (S56.4), other extensor muscle, fascia and tendon at forearm level (S56.5), other muscles, fascia and tendons at forearm level (S56.8) and unspecified muscles, fascia and tendons at forearm level (S56.9).

Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.