Dynamic imaging of skeletal muscle contraction in three orthogonal directions

Abstract

In this study, a multidimensional strain estimation method using biplane ultrasound is presented to assess local relative deformation (i.e., local strain) in three orthogonal directions in skeletal muscles during induced and voluntary contractions. The method was tested in the musculus biceps brachii of five healthy subjects for three different types of muscle contraction: 1) excitation of the muscle with a single electrical pulse via the musculocutaneous nerve, resulting in a so-called "twitch" contraction; 2) a train of five pulses at 10 Hz and 20 Hz, respectively, to obtain a submaximum tetanic contraction; and 3) voluntary contractions at 30, 60, and 100% of maximum contraction force. Results show that biplane ultrasound strain imaging is feasible. The method yielded adequate performance using the radio frequency data in tracking the tissue motion and enabled the measurement of local deformation in both the vertical direction (orthogonal to the arm) and in the horizontal directions (parallel and perpendicular to direction of the arm) in two orthogonal cross sections of the muscle. The twitch experiments appeared to be reproducible in all three directions, and high strains in vertical (25 to 30%) and horizontal (-20% to -10%) directions were measured. Visual inspection of both the ultrasound data, as well as the strain data, revealed a relaxation that was significantly slower than the force decay. The pulse train experiments nicely illustrated the performance of our technique: 1) similar patterns of force and strain waveforms were found; and 2) each stimulation frequency yielded a different strain pattern, e.g., peak vertical strain was 40% during 10-Hz stimulation and 60% during 20-Hz stimulation. The voluntary contraction patterns were found to be both practically feasible and reproducible, which will enable muscles and more natural contraction patterns to be examined without the need of electrical stimulation.

Cervical Muscle Activity During Loaded Arm Lifts in Patients 10 Years Postsurgery for Cervical Disc Disease

“…While there is initial evidence of a relationship between the magnitude of electrical muscle stimulation and muscle deformation as well as a linear correlation between the degree of voluntary muscle contraction and the corresponding degree of muscle deformation, 28 further validation of these US measures are required. Differences in the direction of altered muscle activity (increased or decreased activity relative to that shown by control groups) between this and previous studies, may be due to the interpretation of the ultrasound measures.…”

Altered ventral neck muscle deformation for individuals with whiplash associated disorder compared to healthy controls – A case-control ultrasound study

“…2). The magnitude of muscle deformation measured with speckle tracking was positively related to other measurements used to investigate muscle deformation (force measurements and progressive electrical stimulation) (Lopata et al, 2010). The reliability of the speckle tracking analysis method was shown to have excellent test-retest reliability (two-way random absolute agreement single measure intraclass correlation coefficient [ICC)] 0.71-0.97) (Peolsson et al in press).…”

“…With ultrasound, the muscle of interest may be influenced by neighboring tissues or external pressure from the probe. Nevertheless; the ability to investigate deep and superficial muscle functions together, during real time activations (Lopata et al, 2010;Peolsson et al, 2010 makes this method interesting. Speckle tracking is a post-process method for analyzing ultrasound images; it facilitates measuring muscle deformations (elongations and shortenings) and deformation rates, and this information has improved our understanding of real time (Lopata et al, 2010) mechanical neck muscle function in different muscle layers (Peolsson et al, 2012).…”

Mechanical properties of the trapezius during scapular elevation in people with chronic whiplash associated disorders – A case-control ultrasound speckle tracking analysis

“…An insight into muscles' mechanical properties can be gained with speckle tracking which is an analysis from which muscle deformation identified in ultrasound recordings can be measured during movement (Gronlund et al, 2013).The muscle deformation measure of speckle tracking has been examined against estimated measures of multidimensional strain of both electrically induced and voluntary muscle contraction. The measure was found to be both a reproducible and practically feasible method (Lopata et al, 2010). To our knowledge, the only other study M A N U S C R I P T…”