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Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Ultrasonographic analysis of the extensor carpi radialis brevis in asymptomatic individuals
Yukihiro Kajita1, Yusuke Iwahori2, Yohei Harada3
1Department of Orthopaedic Surgery, Aichi Medical University, Japan; Department of Orthopaedic Surgery, Ichinomiya Nishi Hospital, Japan.
Background:
Tennis elbow is characteristically seen as damage at the extensor carpi radialis brevis (ECRB) on ultrasonography. In this study, damage at the origin of the ECRB was investigated using ultrasonography in elbows without complaints pertaining to the joint.
Methods:
We investigated 282 elbows on the dominant side in volunteers who consented to participate in the study and had no complaints or history of trauma to either elbow, no tenderness in the lateral epicondylar region on physical examination, and no pain upon resisted extension of the wrist and/or middle finger with the elbow extended (162 men, 120 women; mean age 62 years, range 21-84 years). On ultrasonography, damage at the origin of the ECRB was defined as low echo or disruption in fiber orientation. Comparison between groups with and without damage was performed based on age, sex, history of sports activity involving the upper extremity, and history of work involving loading of the upper extremity.
Results:
Of the 282 elbows, damage was noted in 60 (21.3%). Comparing the groups with and without damage, mean ages were 66.2 (40-80) years and 60.9 (21-84) years. The group with damage included 31 of 162 (18.1%) male elbows and 29 of 110 (26.4%) female elbows; 10 of 64 elbows (15.6%) had a positive history of sports involving the upper extremity and 50 of 218 elbows (22.9%) had no history; 16 of the 64 elbows (25.0%) had a positive history of work involving loading the upper extremity and 44 of the 218 elbows (20.2%) had no history. Age was significantly higher in the group with damage. The group with damage showed no significant differences in other categories.
Conclusions:
Asymptomatic damage at the ECRB origin was noted in 21.3% of elbows at higher ages, but there was no association with sports or work.
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