Editor – Keelan et al1 describe an interesting patient with bilateral phrenic nerve palsies, which they ascribe to cervical spondylosis. The phrenic nerve arises mostly from C4 with contributions from C3 and C5. It would be quite exceptional, if not anatomically impossible, for cervical spondylosis to affect only those fascicles destined for the phrenic nerves, without any clinical evidence of a myelopathy or other radicular signs. They cite eight reported cases, seven of which had a myelopathy and one that was unilateral. A much more likely diagnosis is neuralgic amyotrophy, which may be bilateral in up to 30% of patients2 and may follow strenuous exercise (17%2), as in this patient who was lifting heavy iron tables the day before the onset of symptoms. Phrenic nerve palsy, both unilateral and bilateral is well described in neuralgic amyotrophy and maybe the presenting and only feature.3–7
Conflicts of interest
The author has no conflicts of interest to declare.
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