Which time?By "lorica" you possibly mean specifically segmental form of armor?But that is(modernly)called lorica segmentata/laminata."Lorica" alone is not identifiing specifically this type of armour.That word simply means "an armour(any armour) and all major types of Roman used armours are called "lorica" with only that 2nd part acrually refering to specific type(L.segmentata,L.squamata,L.hamata...).This is meant to be late 1st,early 2nd century and at that time segmental arm protector was safely in use(as additional protection used by some soldiers not all).
Such limb protection was however used also after most of them turned to Christianity.