Mixed latency difference for diagnosis of XXXX at the elbow.

@entity1 @entity16
OBJECTIVE: To provide reference values and to compare this technique with the standard motor conduction velocity (MCV) of the ulnar nerve. DESIGN: Retrospective unmasked study. SETTING: Private and institutional practice. @entity1 : The reference group included 57 healthy volunteers. @entity1 included 100 subjects with suspected @entity16 at the elbow (UNE) referred for neurophysiologic evaluation. This group was subdivided into 2 groups: group A was composed of 45 @entity1 with UNE confirmed by MCV of the ulnar nerve, and group B included 55 @entity1 with suspected UNE in whom the diagnosis could not be established by MCV of the ulnar nerve. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Differences between peak latencies of ulnar and median mixed nerve action potentials at the arm, after stimulating these nerves at the wrist. This was called mixed latency difference. RESULTS: The upper normative limit of the mixed latency difference was 1.1 ms, and there was a significant correlation with height. In group A, the mixed latency difference was abnormal in 80% of the cases and could not be calculated in 18%. In group B, the mixed latency difference was abnormal in 8 (15%) @entity1 . All of these had abnormal "inching" of the ulnar nerve across the elbow. CONCLUSIONS: The mixed latency difference was particularly useful in cases of mild UNE.
