High noon back pain- severe pseudoradicular pain as a lead symptom of superficial siderosis: a case report.

A superficial siderosis of the central nervous system following a traumatic cervical nerve root avulsion usually leads to gait difficulties and hearing loss, whereas back pain is described only rarely. Here we report on the first case with circadian occurrence of severe back pain as the only symptom of a superficial siderosis. We present a case with the most severe pseudoradicular lumbosacral pain occurring daily at noon for the past 5 weeks. The 48-year-old male white patient did not complain of pain in the morning. A traumatic root avulsion 26 years earlier led to a brachial plexus palsy and Horner's syndrome in this patient. Superficial hemosiderosis in cranial MRI and examination of the cerebrospinal fluid revealing massive red blood cells as well as xanthochromia and elevated protein levels (742 mg/l) led to the diagnosis of a superficial siderosis. A pseudomeningocele caused by a cervical nerve root avulsion is described as a rare reason for superficial siderosis. Surgery on a pseudomeningocele, diagnosed by MRI, led to an immediate disappearance of complaints in our case. Regular neurological investigation and possibly repeated lumbar puncture to exclude superficial siderosis should be considered in cases with severe back pain and a history of traumatic root avulsion. Modern susceptibility weighted MR imaging (SWI) techniques, sensible to the detection of superficial hemosiderosis, might be helpful in the making of a diagnosis.