Sentence:  By Nov. 8 , 1958 , weakness , specifically involving the pelvic and thigh musculature , was pronounced , and a common complaint was `` difficulty in stepping up on to <WSD>curbs</WSD> '' . 
Meaning of the word marked with <WSD> tags:  an edge between a sidewalk and a roadway consisting of a line of curbstones (usually forming part of a gutter)