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 0SN8X
Release Left Sacroiliac Joint, Open Approach
Release Left Sacroiliac Joint, External Approach
Release Left Sacroiliac Joint, Percutaneous Approach
Release Left Sacroiliac Joint, Perc Endo Approach