Prolonged phone-call posture causes changes of ulnar motor nerve conduction across elbow

• Calling by mobile phone forces the elbow in flexed position.
• The study assesses ulnar nerve function changes during a 18 min phone posture, comparing subjects with minimal clinical UNE and symptom-free subjects.
• Motor nerve conduction of ulnar nerve across the elbow decreases significantly in the UNE group during prolonged phone posture.

ObjectivePostures and work-hobby activities may play a role in the origin and progression of ulnar neuropathy at the elbow (UNE), whose occurrence appears to be increasing. The time spent on mobile-phone has increased in the last decades leading to an increased time spent with flexed elbow (prolonged-phone-posture, PPP). We aimed to assess the effect of PPP both in patients with symptoms of UNE and in symptom-free subjects.MethodsPatients with pure sensory symptoms of UNE and negative neurophysiological tests (MIN-UNE) and symptom-free subjects were enrolled. We evaluated ulnar motor nerve conduction velocity across elbow at baseline and after 6, 9, 12, 15, and 18 min of PPP in both groups. Fifty-six symptom-free subjects and fifty-eight patients were enrolled. Globally 186 ulnar nerves from 114 subjects were studied.ResultsConduction velocity of ulnar nerve across the elbow significantly changed over PPP time in patients with MIN-UNE, showing a different evolution between the two groups.ConclusionsPPP causes a modification of ulnar nerve functionality in patients with MIN-UNE.SignificancePPP may cause transient stress of ulnar nerve at elbow.