Cervical radiculopathy or Parsonage-Turner syndrome: differential diagnosis of a patient with neck and upper extremity symptoms

Resident's case problem. The signs and symptoms of cervical radiculopathy (CR) warrant the consideration of several other conditions in CR's differential diagnosis. One condition that may mimic CR, which is not well known amongst physical therapists, is Parsonage-Turner syndrome (PTS). PTS is characterized by an onset of intense pain that typically subsides within days to weeks. However, as pain subsides, weakness and/or paralysis may develop in upper extremity muscles. The purpose of this resident's case problem is to describe a patient who presented to our clinic with a diagnosis of CR, but had findings consistent with PTS. The patient was a 43-year-old male referred to physical therapy with a diagnosis of CR. He had a previous episode of CR 1 year ago that was treated successfully. He had positive magnetic resonance imaging findings of structural abnormalities suggestive of causative factors for CR. The patient was treated for CR with thoracic and cervical spine manipulations and intermittent cervical traction. The initial acute severe pain subsided, but weakness in the upper extremity worsened. Diagnosis of PTS was made upon exclusion of other potential confounding diagnoses and the findings of fibrillation potentials and positive waves in electrodiagnostic studies. CR and PTS are characterized by pain in the cervical spine, shoulder, and upper extremity. CR generally has an insidious onset, while PTS has a rapid onset of intense pain. Symptoms of CR are exacerbated with neck movements, while symptoms related to PTS should not be exacerbated with neck movements. In patients that do not respond to conventional therapy and have a progression of upper extremity muscle weakness, regardless of decreased pain, the diagnosis of PTS should be considered.