Spinal Accessory Neuropathy Associated With the Tumor Located on the Jugular Foramen
An 18-year-old male visited the clinic with complaints of constant dull ache located in the right shoulder girdle, associated with sudden difficulty with overhead activities and heavy lifting. There was no report of history of neck trauma or manipulation that would predispose the patient to injury. A week later, the pain was worsened. There were no associated episodes of headaches, nausea and vomiting or numbness in right upper extremity.\nPhysical examination revealed winging of the patient's right scapula and severe atrophy of the right trapezius muscle (). Moreover, there was weakness in contralateral rotation and ipsilateral flexion of the neck on the right side. Passive range of motion of his right shoulder joint was normal. Manual muscle test grade was poor plus in flexion and abduction; and normal in external and internal rotation on his right shoulder. The patient was unable to abduct and flex the right arm forwardly to more than 70 to 80 degrees (). There were normal muscle tone, normal sensory function and symmetrical upper extremity reflexes. Hawkins', Neer's, Roos', Wright's, and Adson's provocative tests were all negative.\nThe magnetic resonance imaging (MRI), nerve conduction study (NCS), and electromyography (EMG) on the right shoulder were performed to determine the cause of weakness and pain, on the basis of history and physical examination.\nThe MRI demonstrated increased signal intensity at the supraspinatus muscle. This finding was suggestive of partial tear of supraspinatus muscle on the articular surface. NCS and EMG were carried out almost 10 days after the onset of symptoms. NCS of the SANs showed low amplitude and prolonged latency of nerve potential of the right side when compared with the left side (). EMG studies revealed positive sharp waves at rest () and reduced recruitment, normal morphology, regular firing pattern, and stable stability on volition in the right upper trapezius and SCM muscle. The other examined muscles in both the upper extremities showed no denervation potentials. These findings were consistent with the SAN, involving proximal to the innervation site of SCM. The proximal segment of SAN was considered the following causes, such as the space-occupying lesion in the head and neck, trauma injury or infection. Cervical MRI revealed no abnormal findings. However, MRI of the brain showed a 19×19×20 mm-sized mass in the right jugular foramen. The tumors located on the jugular foramen were most commonly paragangliomas, schwannomas, and meningiomas. The lesion was hyperintense to brain parenchyma on T1-weighted series and of low signal on T2-weighted series. Subsequently, computed tomography (CT) of the temporal bone was performed where axial images revealed relatively smooth expansion of the right jugular foramen (). Cerebral angiography revealed no vascular abnormalities.\nBecause of presumed nerve injury associated with the tumor located on the jugular foramen, surgical approach was needed potentially. However, operation was adjourned due to patient's personal reasons. During the follow-up, the patient was treated intermittently for the SAN such as with electrical stimulation therapy and exercise. After 10 months, he visited our clinic for follow-up study. There were no gross interval changes on the previous findings on brain MRI of the 19×19×22 mm-sized tumor (). And there was no aggravation of the symptoms.