Does ulnar nerve dislocation at the elbow cause neuropathy?

Abstract

The role of ulnar nerve dislocation in the pathogenesis of ulnar neuropathy at the elbow (UNE) is not clear. Data exist for and against a causal relationship. We studied UNE patients and controls divided into 4 groups consisting of 203 UNE patient arms (185 with abnormal and 18 with normal diagnostic studies) and 49 controls (10 with abnormal and 39 with normal studies). In all arms we performed neurologic examination, short-segment nerve conduction studies (SSNCS), and ultrasonography (US). The frequency of partial and complete nerve dislocation was calculated in each group. Dislocation tended to be more common in controls compared with UNE patients (P = 0.056). It was particularly common in controls with subclinical UNE and patients with UNE symptoms but normal diagnostic studies. Our data speak against a causal relationship between ulnar nerve dislocation and UNE. However, the findings also suggest that dislocation may cause mild ulnar nerve damage.