A 79-year-old right-handed woman presented with an indirect trauma to her left shoulder after a fall down the stairs. X-rays and computed tomography showed a four-part glenohumeral fracture-dislocation with a subcutaneous ectopic location of the humeral head in the retroclavicular space. A reverse total shoulder arthroplasty was performed using a deltopectoral approach with direct superior extraction of the humeral head. The result at 2 years was a subjective shoulder value of 80%, an absolute Constant score of 59, and a relative Constant score of 92/100. To the best of our knowledge, this is the first description in the literature of such a lesion of superior glenohumeral fracture-dislocation and its treatment.