Green’s Dictionary of Slang

1. (UK Und.) a deliberately created ‘scar’ or ‘wound’used to elicit sympathy when begging.

1845

Morn. Post 29 Mar. 7/2: If they got what they called good ‘scaldrums’ most let the bone be seen either on one or both arms.

2. (UK Und.) a beggar who practises the scaldrum dodge n.

1984

Partridge DSUE (8th edn) 1016/1: mid-C.19–early 20.