Short segment stimulation of the anterior transposed ulnar nerve at the elbow

Objective: To determine whether short segment stimulation after anterior subcutaneous transposition of the ulnar nerve reaches normal values and correlates with postoperative clinical findings. Design: Comparative cross-sectional study. Setting: Outpatient clinic of a university department of physical medicine and rehabilitation. Patients: Nineteen patients (15 men, 4 women) with 21 surgically treated ulnar neuropathies at the elbow; and 19 healthy controls (11 men, 8 women) with 24 measured nerves. Interventions: Assessed motor function of ulnar innervated muscles and staged into 4 categories; used questionnaire to assess clinical course of the nerve lesion and graded into 5 categories; took electrophysiologic recordings to measure motor conduction velocity and compound muscle action potentials; and studied short segment stimulation across elbow and lower arm. Main Outcome Measures: Mean standard deviation of ulnar short segment conduction time across the elbow, amplitude and motor conduction velocity; grading of ulnar nerve lesions; grading of the course of disease after surgery; and logistic regression and correlation (Spearman's correlation coefficient) for electrophysiologic and clinical parameters. Results: Sixteen nerves showed focal conduction slowing in patients. No significant correlation between the course of disease and electrophysiologic parameters was seen. For stepwise logistic regression, there was a significant effect between grade of nerve lesion and amplitude, but no significant effect between the course of disease and electrophysiologic parameters. Conclusion: A focal conduction slowing across the elbow after anterior subcutaneous transposition does not correlate with postoperative clinical findings.