concordo con te. Se guardi in rete, ci sono moltissimi record per spalla (pochi per spallina).
Al singolare.....
http://www.google.it/#sclient=psy-ab&hl=it&source=hp&q="dist...

Shoulder sleeve insignia receive their name from the fact that they are most commonly worn on the upper left shoulders of all US Army uniforms, though they can be placed on other locations, notably a combat helmet. Shoulder sleeve insignia worn on the upper right shoulders on Army uniforms denote former wartime service. These "combat patches" will not be worn on the new Army service uniform. Instead a 2 inch metal replica will be worn on the right breast pocket and is officially known as the Combat Service Identification Badge.

http://en.wikipedia.org/wiki/Shoulder_sleeve_insignia

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