Latency and CMAP of the CubTS group that was in abnormal distribution were expressed as median and quartiles.
To solve this paradoxical problem, two studies had investigated the influence of elbow position in sensitivity of CubTS diagnosis by NCS but drew different conclusions.
There was also no statistically significant difference in abnormality and diagnosis of CubTS between full elbow extension and 70[degrees] elbow flexion as measured by SSNCS.
In our study, maintaining the patient's elbow in full extension or 70[degrees] flexion made no statistically significant difference in diagnosis of CubTS, and results were highly correlated across the elbow where most CubTS occurred.
When diagnosed CubTS for the first time, 16 patients had numbness in the distribution of ulnar nerve, 4 patients had abduction weakness of digitus minimus along with paresthesia of ulnar nerve distribution of elbow, 2 patients had atrophy of intrinsic muscle of hands.
Probable pathogenesis of CubTS includes: (1) When elbow is in flexion, the fibrous aponeurosis becomes thicker between the two heads of musculi flexor carpi ulnaris, which is the lateral wall of cubital tunnel, narrowing the cubital tunnel lacuna, making ulnar nerve compressed; [sup] (2) Compression of ulnar nerve across the elbow by hyperosteogeny or osteophyma, which aggravates the tunnel's narrowing; [sup] (3) Induced by soft tissue adjacent to the ulnar nerve in the tunnel; [sup] (4) Compressed by intraluminal mass; [sup] (5) When flex the elbow, cubital tunnel volume decreased, elbow support ligament contracted, and ulnar nerve compressed.
sup] reported that in 53 patients who were diagnosed CubTS by short-segment conduction study, 27% lesions were in the medial epicondyle, 20% in the digital of medial epicondyle.
In this study, all the patients diagnosed CubTS by routine motor nerve conduction test, had symptoms such as limb numbness.