A 49-year-old secretary visits her GP as she is becoming increasingly worried about numbness and tingling in both of her hands. She mentions that it affects the lateral three and a half fingers and it often wakes her at night

b. This lady is describing symptoms of median nerve palsy. In addition to these symptoms she may note a weakness in the muscles of her thenar eminence with associated wasting. This is likely to be caused by carpal tunnel syndrome, which results in compression being applied to the median nerve as it passes under the flexor retinaculum on the palmar aspect of the wrist. If this is the cause it can be treated with a carpal tunnel decompression, although since she is complaining of bilateral symptoms the cause may result from a lesion of the cervical vertebrae.