[The most significative parameters for the diagnosis of focal neuropathy of the cubital nerve in the elbow].

OBJECTIVE

Determine the diagnostic validity of the most usual neurophysiological procedures in the examination of compressive neuropathies and/or ulnar nerve entrapment at the elbow.

PATIENTS AND

METHODS

A prospective observational study was carried out over a period of one year which included 19 patients with clinical features compatible with entrapment/compression of the ulnar nerve at the elbow, their neurophysiological diagnosis and surgical confirmation. We also studied 49 patients who were attended in our clinic for other reasons not related to disorders of the ulnar nerve. The variables studied were: maximum rate of motor conduction above the elbow; the amplitudes between spikes and the area between the first negative deflection and the last positive spike of the responses at the wrist and above the elbow.

RESULTS

In the group of persons without disorders of the ulnar nerve the average rate of motor conduction was 58.07 m/s, with a confidence interval of 53-65. In the group of patients with specific clinical features the average rate of motor conduction was 47.26 m/s, with a confidence interval of 43.74-50.77. No relation was found between age and pathology, although rate of motor conduction was related to the presence of pathology.

CONCLUSIONS

It was seen on logistical regression that the main variables for prediction of the presence or absence of pathology in a person were firstly motor conduction and secondly the amplitude index.