Neuralgic Amyotrophy Following Robotic-Assisted Nipple-Sparing Mastectomy: A Case Report

Neuralgic amyotrophy (NA) is an acute inflammatory peripheral neuropathy that affects the brachial plexus and its branches.Although postoperative NA is a recognized clinical entity, its occurrence after breast cancer surgery, particularly robotic-assisted nipple-sparing mastectomy, is exceptionally rare.We report the case of a 47-year-old woman who developed severe right shoulder pain immediately after robotic-assisted right nipple-sparing mastectomy, followed by sudden-onset weakness and hypoesthesia in the right upper extremity.Initial nerve conduction studies performed on postoperative day (POD) 3 were within normal limits and showed no evidence of conduction block.Because the symptoms persisted, brachial plexus magnetic resonance imaging (MRI) was performed on POD 10 and revealed distinct thickening of the right brachial plexus trunk, with denervation edema in the supraspinatus, infraspinatus, and deltoid muscles.Subsequent electrodiagnostic evaluation on POD 14 demonstrated active denervation in the right supraspinatus and deltoid muscles, along with isolated loss of the lateral antebrachial cutaneous sensory response, consistent with selective fascicular involvement of NA.After oral corticosteroid administration, the patient's motor weakness and sensory symptoms gradually improved.This report emphasizes that NA should be included in the differential diagnosis, along with direct mechanical injury, when unilateral upper-extremity weakness occurs after robotic-assisted breast surgery.In similar cases, early MRI combined with follow-up electrodiagnostic evaluation may support accurate diagnosis.