Use of muscle thickness change to control powered prosthesis: A pilot study

Abstract Skeletal muscle thickness is a valuable indicator of several aspects of a muscle’s functional capabilities. We used computational analysis of ultrasound images, recorded from 10 humans walking and running at a range of speeds (0.7–5.0 m s−1), to quantify interactions in thickness change between three ankle plantar flexor muscles (soleus, medial and lateral gastrocnemius) and quantify thickness changes at multiple muscle sites within each image. Statistical analysis of thickness change as a function of stride cycle (1d statistical parametric mapping) revealed significant differences between soleus and both gastrocnemii across the whole stride cycle as they bulged within the shared anatomical space. Within each muscle, changes in thickness differed between measurement sites but not locomotor condition. For some of the stride, thickness measures taken from the distal-mid image region represented the mean muscle thickness, which may therefore be a reliable region for these measures. Assumptions that muscle thickness is constant during a task, often made in musculoskeletal models, do not hold for the muscles and locomotor conditions studied here and researchers should not assume that a single thickness measure, from one point of the stride cycle or a static image, represents muscle thickness during dynamic movements.

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Cocontraction of Ankle Dorsiflexors and Transversus Abdominis Function in Patients With Low Back Pain

Journal of Athletic Training ◽

10.4085/1062-6050-47.4.12 ◽

2012 ◽

Vol 47 (4) ◽

pp. 379-389 ◽

Cited By ~ 2

Author(s):

Seung-Chul Chon ◽

Joshua H. You ◽

Susan A. Saliba

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Onset Time ◽

Muscle Thickness ◽

Transversus Abdominis ◽

Low Back ◽

Control Groups ◽

Thickness Change ◽

And Control ◽

Ankle Dorsiflexors

Context: The abdominal draw-in maneuver (ADIM) with cocontraction has been shown to be a more effective method of activating the transversus abdominis (TrA) in healthy adults than the ADIM alone. Whether such an augmented core stabilization exercise is effective in managing low back pain (LBP) remains uncertain. Objective: To determine the effect of 2 weeks of ADIM and cocontraction training on abdominal muscle thickness and activation timing and to monitor pain and function in patients with LBP. Design: Case-control study. Setting: Local orthopaedic clinic and research laboratory. Patients or Other Participants: Twenty patients with mechanical LBP (age = 27.20 ± 6.46 years, height = 166.25 ± 8.70 cm, mass = 58.10 ± 11.81 kg) and 20 healthy, age-matched people (age = 24.25 ± 1.59 years, height = 168.00 ± 8.89 cm, mass = 60.65 ± 11.99 kg) volunteered for the study. Intervention(s): Both the LBP and control groups received ten 30-minute sessions of ADIM and cocontraction training of the tibialis anterior (TA) and rectus femoris (RF) muscles over a 2-week period. Main Outcome Measure(s): A separate, mixed-model analysis of variance was computed for the thicknesses of the TrA, internal oblique (IO), and external oblique muscles. The differences in mean and peak electromyographic (EMG) amplitudes, onset time, and latency were compared between the groups. The visual analog pain scale, Pain Disability Index, and LBP rating scale were used to assess pain in the LBP group before and after the intervention. Results: We found an interaction between the LBP and control groups and a main effect from pretest to posttest for only TrA muscle thickness change (F1,38 = 6.57, P = .01). Reductions in all pain measures were observed after training (P < .05). Group differences in peak and mean EMG amplitudes and onset time values for TrA/IO and TA were achieved (P < .05). The RF peak (t38 = −3.12, P = .003) and mean (t38 = −4.12, P = .001) EMG amplitudes were different, but no group difference was observed in RF onset time (t38 = 1.63, P = .11) or the cocontracted TrA/IO peak (t38 = −1.90, P = .07) and mean (t38 = −1.81, P = .08). The test-retest reliability for the muscle thickness measure revealed excellent correlations (intraclass correlation coefficient range, 0.95–0.99). Conclusions: We are the first to demonstrate that a cocontraction of the ankle dorsiflexors with ADIM training might result in a thickness change in the TrA muscle and associated pain management in patients with chronic LBP.

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Gastrocnemius Medialis Architectural Properties in Flexibility Trained and Not Trained Child Female Athletes: A Pilot Study

Sports ◽

10.3390/sports8030029 ◽

2020 ◽

Vol 8 (3) ◽

pp. 29 ◽

Cited By ~ 1

Author(s):

Ioli Panidi ◽

Gregory C. Bogdanis ◽

Vasiliki Gaspari ◽

Polyxeni Spiliopoulou ◽

Anastasia Donti ◽

...

Keyword(s):

Pilot Study ◽

Distal Part ◽

Joint Angle ◽

Female Athletes ◽

Muscle Thickness ◽

Pennation Angle ◽

Static Stretching ◽

Fascicle Length ◽

Gastrocnemius Medialis ◽

Ankle Angle

Gastrocnemius medialis (GM) architecture and ankle angle were compared between flexibility trained (n = 10) and not trained (n = 6) female athletes, aged 8–10 years. Ankle angle, fascicle length, pennation angle and muscle thickness were measured at the mid-belly and the distal part of GM, at rest and at the end of one min of static stretching. Flexibility trained (FT) and not trained athletes (FNT) had similar fascicle length at the medial (4.19 ± 0.37 vs. 4.24 ± 0.54 cm, respectively, p = 0.841) and the distal part of GM (4.25 ± 0.35 vs. 4.18 ± 0.65 cm, respectively, p = 0.780), similar pennation angles, and muscle thickness (p > 0.216), and larger ankle angle at rest (120.9 ± 4.2 vs. 110.9 ± 5.8°, respectively, p = 0.001). During stretching, FT displayed greater fascicle elongation compared to FNT at the medial (+1.67 ± 0.37 vs. +1.28 ± 0.22 cm, respectively, p = 0.048) and the distal part (+1.84 ± 0.67 vs. +0.97 ± 0.97 cm, respectively, p = 0.013), larger change in joint angle and muscle tendon junction displacement (MTJ) (p < 0.001). Muscle thickness was similar in both groups (p > 0.053). Ankle dorsiflexion angle significantly correlated with fascicle elongation at the distal part of GM (r = −0.638, p < 0.01) and MTJ displacement (r = −0.610, p < 0.05). Collectively, FT had greater fascicle elongation at the medial and distal part of GM and greater MTJ displacement during stretching than FNT of similar age.

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