break (one's) arm patting (oneself) on the back

(redirected from break their arms patting themselves on the backs)

break (one's) arm patting (oneself) on the back

To excessively praise oneself for an achievement or a job well done. Tony was instrumental in the success of the merger—or so he says. He's going to break his arm patting himself on the back.
See also: arm, back, break, on, pat