Parsonage-turner syndrome; This literature-non-study case was reported in a literature article and describes the occurrence of NEURALGIC AMYOTROPHY (Parsonage-turner syndrome) in a male patient of an unknown age who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination.   No Medical History information was reported.    On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced NEURALGIC AMYOTROPHY (Parsonage-turner syndrome) (seriousness criterion medically significant). At the time of the report, NEURALGIC AMYOTROPHY (Parsonage-turner syndrome) was resolving.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Diagnostic procedure: abnormal (abnormal) Electrodiagnostic evaluation 2 months after symptom onset revealed mononeuritis multiplex involving the suprascapular and anterior interosseous nerve with abnormal spontaneous activity and polyphasic units in the supraspinatus and infraspinatus, and polyphasic units in flexor pollicis longus.  The clinical presentation and electrodiagnostic findings were consistent with a diagnosis of Parsonage-Turner syndrome (PTS).. On an unknown date, Physical examination: abnormal (abnormal) noted to have 4/5 in left shoulder abduction and 3/5 external rotation strength, with left infraspinous fossa atrophy and scapular dyskinesis..     The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered NEURALGIC AMYOTROPHY (Parsonage-turner syndrome) to be related.    Concomitant product and treatment medication use was not provided by the reporter. The patient presented to musculoskeletal clinic 1 month after onset of severe left shoulder pain and weakness. Symptoms started without trauma or inciting event. Pain lasted for 2 weeks, but he had persistent weakness. He did report having his first dose of COVID-19 vaccine 10 days prior.  Company comment: This literature non-study case concerns a male patient of unknown age with no medical history reported, who experienced the unexpected serious (medically significant) event of Neuralgic amyotrophy after mRNA- 1273 Moderna vaccine. The onset of the event occurred approximately 10 days after the first dose of mRNA- 1273 vaccine. Clinical manifestations included left shoulder pain of 2-week duration and persistent left should weakness . Physical examen showed diminished strength in left shoulder abduction and external rotation, with left infraspinous fossa atrophy and scapular dyskinesis. Electrodiagnostic evaluation 2 months after symptom onset revealed Mononeuritis multiplex involving the suprascapular and anterior interosseous nerve with abnormal spontaneous activity and polyphasic units in the supraspinatus and infraspinatus, and polyphasic units in flexor pollicis longus. Very limited information is available regarding clinical course and treatment. The benefit-risk relationship of mRNA- 1273 vaccine is not affected by this report.   Reporter did not allow further contact; Sender's Comments: This literature non-study case concerns a male patient of unknown age with no medical history reported, who experienced the unexpected serious (medically significant) event of Neuralgic amyotrophy after mRNA- 1273 Moderna vaccine. The onset of the event occurred approximately 10 days after the first dose of mRNA- 1273 vaccine. Clinical manifestations included left shoulder pain of 2-week duration and persistent left should weakness . Physical examen showed diminished strength in left shoulder abduction and external rotation, with left infraspinous fossa atrophy and scapular dyskinesis. Electrodiagnostic evaluation 2 months after symptom onset revealed Mononeuritis multiplex involving the suprascapular and anterior interosseous nerve with abnormal spontaneous activity and polyphasic units in the supraspinatus and infraspinatus, and polyphasic units in flexor pollicis longus. Very limited information is available regarding clinical course and treatment. The benefit-risk relationship of mRNA- 1273 vaccine is not affected by this report.