Abstract:
Background: Extensive use of mobile hand-held devices with prolonged forearm pronation and elbow flexion could result in pain and weakness with decreased nerve conduction velocities (NCV) of peripheral nerves.
Purpose: To identify the ulnar nerve conduction velocity at different forearm positions across elbow joint in mobile-hand held devices users.
Design of the study: One shot case study
Subjects: Fifty healthy subjects from both genders, Their age ranged from 20 to 40 years old. All subjects had body mass index BMI between 18.5 and 24.9 Kg/m2.
Method: Electromyography (EMG) was used for measuring ulnar NCV across elbow joint at different angles (0, 45, and 90,120) degrees of elbow flexion with different forearm positions (supination and pronation).
Result: Multivariate Analysis of Variance (MANOVA) revealed that there was a statistical significant difference in mean values of ulnar nerve conduction velocities at different angles of elbow flexion with forearm supination and pronation (P=0.001). There was a statistical significant difference in mean values of ulnar nerve conduction velocities between forearm pronation and supination at the different angles of elbow flexion (P=0.001).
Conclusion: forearm supination with full extension elbow position showed the most significant increase in ulnar nerve conduction velocity than other positions. As well as the best position for elbow joint during using mobile hand held devices is 0°-45° elbow flexion with elbow supinated.