According to table 6-10: Critical Injury Result (pg.231), each result has an associated Severity rating of purple diamonds. What do these reference? There doesn't appear to be any check that references these when taking the Critical Injury. Are they associated with their removal? I can't seem to find any reference for these check ratings in the book.

Ugh, nevermind me. I just found the answer. (Pg.232) Medicine checks can be made with difficulty equal to the Severity rating of the Critical Injury.

Apparently while the immediate effects of "drop what you're holding" are resolved once, just carrying the Critical Injury around is enough to cause you trouble. They can increase further Crits to you by +10 for each one. So, better get them looked after.