University of Tasmania
Browse

File(s) under permanent embargo

Muscle activity during rapid wrist extension in people with lateral epicondylalgia

journal contribution
posted on 2023-05-21, 04:59 authored by Nagarajan ManickarajNagarajan Manickaraj, Bisset, LM, Ryan, M, Kavanagh, JJ

Background: Individuals with lateral epicondylalgia (LE) have delayed upper limb reaction time (RT); however, it is unknown if the mechanisms of this dysfunction are related to neural processing or the affected forearm muscles. The aim of this study was to examine the timing of processes that occur before and after forearm muscles are activated during the RT task.

Methods: Eleven LE (42 ± 11 yr) and 11 healthy controls (42 ± 11 yr) performed rapid wrist extension in response to an audio cue. Intramuscular EMG was obtained from extensor carpi radialis brevis (ECRB), extensor digitorum communis (EDC), extensor carpi ulnaris (ECU), and anconeus. Premotor time (PMT) was the duration from an audio cue to the onset of muscle activity, and motor time (MT) was the onset of muscle activity to the onset of wrist extension. Standard clinical assessments of LE were also performed.

Results: RT was significantly slower (33; 95% CI, 1-66 ms) in the LE group. There were no group differences in PMT and the order of muscle activation. Instead, the MT of ECRB (18; 95% CI, 6-31 ms), EDC (12; 95% CI, 1-23 ms), ECU (28; 95% CI, 9-46 ms), and anconeus (33; 95% CI, 11-56 ms) showed significant delay in LE group. Regression analyses revealed that the duration of LE could predict RT, ECRB, and anconeus PMT, whereas cold pain threshold predicted ECRB MT.

Conclusions: Delayed RT in LE was predominantly caused by deficits in ECRB and EDC MT. This study provides preliminary evidence that in the people with longer LE symptoms, duration appeared to have faster RT, although confirmation of this finding is required before firm conclusions can be drawn.

History

Publication title

Medicine and Science in Sports and Exercise

Volume

48

Issue

4

Pagination

599-606

ISSN

0195-9131

Department/School

School of Health Sciences

Publisher

Lippincott Williams & Wilkins

Place of publication

530 Walnut St, Philadelphia, USA, Pa, 19106-3621

Rights statement

Copyright © 2016 by the American College of Sports Medicine.

Repository Status

  • Restricted

Socio-economic Objectives

Diagnosis of human diseases and conditions

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC