683 - Orchestrating Relief: Managing Thoracic Outlet Syndrome In a Violinist

A 51-year-old female violinist presented in 2020 with weakness and paresthesias in her right arm after a motor vehicle crash. Nerve conduction studies (NCS) and Electromyography (EMG) confirmed a right ulnar neuropathy, which improved with therapy. 4 years later she returned with ulnar distribution pain now made worse with violin work, and complicated by a recent non-COVID-19  infection. Physical exam revealed diffuse tenderness of the anterior shoulder, 4+/5 strength in the right extremity, and diminished sensation over the right 4th and 5th digits. There were no dropped reflexes. MRI of the brain, cervical region, and right arm were noncontributory. NCS and EMG demonstrated no abnormalities, compared to the 2020 testing. She was referred to a TOS specialist to receive a diagnostic block with immediate resolution of symptoms confirming her NTOS diagnosis.

Discussions: This case highlights the diagnostic challenges of TOS, especially with previous neuropathic history. The 2024 presentation of symptoms might have been mistaken as a recurrence of the 2020 neuropathy and treated conservatively with PT, likely offering less benefit to the patient. Despite the negative EMG, TOS was not ruled out and a broad and unbiased differential was maintained throughout the evolution of a clinical diagnosis.

Conclusions: Keeping a wide differential to include TOS can help catch new cases and expedite the time to treatment. It can be challenging to diagnose TOS given its multiple subtypes, frequent idiopathic origin, and symptom overlap. It is important to consider the entire history, exam, and diagnostic testing. Keeping TOS on the differential can help identify new cases and improve patient outcomes.