Ultrasound of the Month – Case 116
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Diagnosis: Bifid Median Nerve with a Persistent Median Artery Discussion The bifid median nerve has a prevalence of 3% in the general population. In this normal variant, the nerve divides into two bundles in the distal forearm rather than dividing into its branches just distal to the carpal tunnel, which is the most common anatomy. The bifid median nerve may be accompanied by an artery, the persistent median artery, coursing between the two bundles. The bifid median nerve, with or without a persistent median artery, is thought to be a risk factor for carpal tunnel syndrome, as it is overall larger than a normal median nerve and thus more prone to compression in the carpal tunnel. The presence of a bifid median nerve with or without a persistent median artery is important for the hand surgeon to be aware of preoperatively so that an inadvertent injury to the nerve or the artery can be avoided.
Ultrasound of the Month – Case 116
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