Publications by authors named "Luke Van Wyk"

Isometric strength and endurance performance of cervical flexor and extensor muscles were compared in women with (n = 30) and without (n = 30) idiopathic neck pain at the craniocervical and cervicothoracic axes. Strength and endurance time (time to task failure in seconds) at 50% maximal voluntary contraction were recorded in 4 directions (craniocervical flexion/extension and cervicothoracic flexion/extension) and 6 strength and endurance ratios were calculated. Participants in both groups were matched for body mass index.

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This study examined isometric strength (maximal voluntary contraction [MVC]) and endurance of cervical flexor and extensor muscles in healthy individuals at the craniocervical (CC) and cervicothoracic (CT) axes. MVC and endurance measures (time to task failure in seconds [s]) at 50% MVC were recorded in 4 directions (CC flexion, CC extension, CT flexion, and CT extension) in 20 males and 20 females, and 6 strength and endurance ratios were calculated. The findings showed that the cervical extensor muscles are not only much stronger than the flexors (1.

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Introduction: In this preliminary study we determined whether MRI markers of cervical muscle degeneration [elevated muscle fatty infiltration (MFI), cross-sectional area (CSA), and reduced relative muscle CSA (rmCSA)] could be modified with exercise in patients with chronic whiplash.

Methods: Five women with chronic whiplash undertook 10 weeks of neck exercise. MRI measures of the cervical multifidus (posterior) and longus capitus/colli (anterior) muscles, neck muscle strength, and self-reported neck disability were recorded at baseline and at completion of the exercise program.

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Study Design: A population based cross-sectional study.

Objective: To clarify relative constituents of viable muscle in 2-dimensional cross-sectional area (CSA) measures of ventral and dorsal cervical muscles in patients with chronic whiplash-associated disorders (WAD), idiopathic neck pain, and healthy controls.

Summary Of Background Data: Previous data using T1-weighted magnetic resonance image demonstrated large amounts of neck muscle fat infiltration and increased neck muscle CSA in patients with chronic WAD but not in idiopathic neck pain or healthy controls.

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The purpose of this study was to compare maximal torque exerted about the craniocervical (CC) and cervicothoracic (CT) axes in the sagittal plane using a novel dynamometry device. Maximal voluntary contraction (MVC) recordings in newton-meters (N·m) were measured in 20 males and 20 females for each of 4 tests: CT extension, CT flexion, CC extension, CC flexion. Twenty of the volunteers repeated the testing procedure on a second occasion to determine the test-retest repeatability of the measures.

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