The Approach External is identified by letter "X" and occupies the 5th position in the ICD10-PCS procedure code structure.
Below a selection of ICD 10 PCS codes related to 0KNFX
Release Right Trunk Muscle, Open Approach
Release Right Trunk Muscle, External Approach
Release Right Trunk Muscle, Percutaneous Endoscopic Approach
Release Right Trunk Muscle, Percutaneous Approach