Which nerve is most commonly affected in Parsonage-Turner Syndrome?

Parsonage-Turner Syndrome is characterized by sudden onset of shoulder pain followed by weakness in the shoulder girdle and arm, likely due to brachial plexus involvement. The long thoracic nerve, which innervates the serratus anterior muscle, is notably susceptible to injury in this condition. Damage to this nerve results in dysfunction leading to winging of the scapula and weakness in shoulder elevation.

In the context of Parsonage-Turner Syndrome, the long thoracic nerve is prominently affected due to its anatomical pathway and the potential for stretch or compression during traumatic or idiopathic circumstances. Most commonly, patients present with pain and weakness that aligns with these nerve dysfunctions. Understanding this helps in recognizing the clinical presentation of the syndrome and in guiding appropriate interventions.

The other nerves listed, such as the axillary, median, and ulnar nerves, can indeed be associated with different types of peripheral nerve injuries but are not the characteristic focus of Parsonage-Turner Syndrome, which emphasizes the involvement of the long thoracic nerve specifically.