Ulnar Nerve Entrapment (Sulcus Nervi Ulnaris Syndrome)

Ulnar nerve entrapment is caused by compression damage of the ulnar nerve at the inner edge of the elbow. Various causes in the vicinity of this naturally narrow channel can ultimately lead to sensory dysfunctions and pain in the area supplied by the ulnar nerve: electrifying pain often radiates from the inside of the elbow along the inner edge of the lower arm through to the area of the little finger and parts of the ring finger, and is frequently attended by numbness. At an advanced stage, the pressure-related damage to the nerve can also lead to a paralysis of the hand's intrinsic musculature with a weakness in the extending and stretching of fingers, and a notable loss of strength. The definition of surgical indications should be preceded by a localization of the nerve damage by means of an electroneurographic examination of the elbow area.

Under regional anaesthesia of the entire arm or under general anaesthesia, the pressure is taken off the ulnar nerve by way of an open portal, and it is brought forward under the musculature of the lower arm from its constricted and mechanically irritating situation. In most cases, however, endoscope-assisted access by way of two short incisions below and above the bottleneck at the elbow will suffice to lay open the nerve, decompress it under endoscopic control, and nonetheless eliminate additional constrictions at the entry and exit of the nerve channel, if required. In the latter technique, the nerve is also not relocated, but can remain in its expanded environment. After the wound is closed with a suture and drained, the operated region is protected with padding and an elastic bandage reaching from the hand to the upper arm. The elbow joint will already be carefully moved through its range of motion a few days after the operation.