Below are the main rubriks (i.e strongest indications or symptoms) of Mercurius Corrosivus in traditional homeopathic usage, not approved by the FDA.
BACK AND NECK
Tonic cramps involving the neck and back, lasting several minutes, during which respiration completely stopped,
Tension externally near the left scapula (first day),
Tearing internally in the upper part of the left scapula, as if in the bone (first day),≡ more ...