Weakness and Irritability in 12-week-old Infant

Abstract

Presentation 12-week-old, term female was brought to the hospital for irritability, progressively worsening reduced left upper extremity movement and left neck swelling. 10 days prior to presentation, she developed irritability with movement, especially when cradled on her left side. She was seen at urgent care; chest X-ray was performed and was read as normal. She was seen again at her primary care office for worsening fussiness; parents were again reassured and sent home. 4 days prior to her presentation, parents noted that she was not moving her left arm. On the day of …