Calcific myonecrosis is a rare and latent condition characterized by a dystrophic calcified lesion that can present 10-64 years following initial trauma. Of the 25 cases documented in English world literature, all have occurred in the lower extremity exclusively. We report a case of a 60-year-old man with a painless enlarging left forearm mass that was subsequently diagnosed as calcific myonecrosis. Awareness of this lesion arising outside of the lower extremity is important to avoid unnecessary surgical intervention and patient reassurance.