Sensitivity of the mixed ulnar nerve action potential investigation.
Research type
Research Study
Full title
The sensitivity of the mixed ulnar nerve action potential investigation in the diagnosis of ulnar nerve entrapment.
IRAS ID
150862
Contact name
Paul Furlong
Contact email
Research summary
This study aims to use an extra nerve conduction study (NCS) in addition to the sensory and motor NCS currently used to measure Ulnar nerve entrapment at the elbow (UNE). This extra investigation is called the mixed nerve action potential (mixed-NAP) investigation and it records responses from motor and sensory nerve fibres. This is because previous literature has suggested that the mixed-NAP investigation is a more sensitive test than currently used sensory and motor NCS. This means that the mixed-NAP investigation may detect milder forms of UNE. The theory behind the mixed-NAP investigation being a sensitive investigation is based on structural studies of different UNE severities. These studies suggested that sensory nerve fibres are preferentially affected than motor nerve fibres. The performance of the mixed-NAP investigation would be beneficial because current sensory NCS for UNE only record responses from locations below the elbow and not at the elbow. Therefore, the mixed-NAP investigation will gain responses from these previously untested sensory fibres. Motor nerves are only believed to be affected when the condition becomes more severe, thus making the mixed-NAP investigation more likely to detect mild UNE. However, this is a controversial point. The mixed-NAP investigation and the motor/sensory-only NCS will be performed on each individual twice. These appointments will be 3 months apart to allow milder UNE to worsen and therefore potentially become detectable by motor/sensory-only NCS. The results of all the investigations at both appointments will then be compared to published normal values to assess UNE severity. The results of the two appointments will be compared in order to analyse the sensitivity of the mixed-NAP investigation in comparison to the motor/sensory-only NCS. The statistical results yielded will be helpful for future patients as they may be able to receive earlier diagnosis of UNE, affording patients potentially better health outcomes.
REC name
London - Bloomsbury Research Ethics Committee
REC reference
14/LO/1215
Date of REC Opinion
5 Aug 2014
REC opinion
Further Information Favourable Opinion