S56.509 - Unspecified injury of other extensor muscle, fascia and tendon at forearm level, unspecified arm S56.5 - Injury of other extensor muscle, fascia and tendon at forearm level S56.50 - Unspecified injury of other extensor muscle, fascia and tendon at forearm level S56.509 - Unspecified injury of other extensor muscle, fascia and tendon at forearm level, unspecified arm