Background & Aims
Male patient, 33 years old who assisted an outpatient pain visit. He presents a clinical background of sudden pain, progressive weakness and muscle atrophy in the right arm, he never had headache nor other associated neurologic symptoms. After the episode, presented flaccid paralysis, weakness and excruciating pain in the right superior extremity. Assisted the emergency room due to severe and persistent neuropathic pain and neurologic symptoms for more than 12 hours. In the ER received pain control with 10 mg of morphine and IV methylprednisolone boluses with no pain modulation. Physicians indicated brain MRI and blood tests with normal findings, no neurologic compromise nor infections that explain symptoms. After 10 day hospitalization, under vigilance and prior assessment for the neurology department the patient persists with neuropathic pain and right arm paresis, neurology decided ambulatory follow up and treatment. The ambulatory management consisted in pregabalin 300 mg bid.
Methods
Brachial plexus neuropathy or Parsonage – Turner syndrome is a rare form of neuritis involving the brachial plexus affecting mainly the shoulder and proximal upper extremity. Has a 1.5 / 100,000 habitants incidence with a peak rate between the third and fifth decades of life having a slight predominance in males. Has an unknown etiology but several studies suggest that there may be triggering factors such as bacterial or viral infections, recent surgical procedures, post immunized patients or recent traumatic background. The physiopathology sequence may be related to perineural edema and complement activation in the acute phase. Is an uncommon neurologic disorder consisting by a sudden and rapid onset of severe neurologic pain in shoulder and upper arm followed by paralysis and amyotrophy. Patient workup consists in imaging studies such as brachial plexus MRI and electrodiagnostic tests such as needle EMG and NCS. Treatment bases in physical and occupational therapy, symptom treatmen
Results
Brain MRI, brachial plexus MRI and blood tests with normal findings. Nerve conduction studies evidenced an amplitude decrease in motor action potential from suprascapular nerve stimulating supraspinatus erb’s point. Electromyography with denervation signs given by positive acute waves and fibrillation waves in the supraspinatus and infraspinatus muscle.
Conclusions
In conclusion the patient was diagnosed with Parsonage Turner Syndrome, managed with physical therapy, occupational therapy and pain modulation. Presented spontaneous recovery 3 months after first symptom arousal and electrophysiological signs of reinnervation in supraspinatus and infraspinatus muscles without any intervention or surgical management. Patient continued with medical treatment and occupational therapy sessions.
References
Briceño Procopio, F., & Rodríguez Montero, S. A. (2010). Síndrome de Parsonage-Turner. Revisión bibliográfica. In Seminarios de la Fundación Española de Reumatología (Vol. 11, Issue 4, pp. 144–151). https://doi.org/10.1016/j.semreu.2010.05.002
Hussey, A. J., O’Brien, C. P., & Regan, P. J. (2007). Parsonage – Turner syndrome – Case report and literature review. Hand, 2(4), 218–221. https://doi.org/10.1007/s11552-007-9059-x
Meiling, J. B., Boon, A. J., Niu, Z., Howe, B. M., Hoskote, S. S., Spinner, R. J., & Klein, C. J. (2024). Parsonage-Turner Syndrome and Hereditary Brachial Plexus Neuropathy. In Mayo Clinic Proceedings (Vol. 99, Issue 1, pp. 124–140). Elsevier Ltd. https://doi.org/10.1016/j.mayocp.2023.06.011