Infant with respiratory distress Pediatric Imaging Musculoskeletal December 2, 2020November 23, 2020 CXR AP shows poorly expanded but grossly clear lungs bilaterally. There is dense periosteal reaction / callus formation around the posterior aspect of the left 8th and 9th ribs. The diagnosis was chronic left 8th-9th posterior rib fractures in a child abuse patient. Related Published December 2, 2020November 23, 2020