Portable fixed dynamometry to quantify ankle dorsiflexion force

Mauracher, Marita E.; Asmussen, Michael J.; Nigg, Sandro; Omu, Onutobor; Jarvis, Scott E.

doi:10.1002/mus.26476

Cited by 2 publications

(1 citation statement)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dorsiflexion MVCF measured at the foot of our participants was 262.2 ± 57.7 N and ranged from 185.5 to 411.5 N, which is in line within the normal range. 39 None of the MRI datasets showed any motion or fat artifacts and all diffusion datasets were of sufficient SNR (> 20) and thus were included in the statistical analyses.…”

Section: Study Population and Data Qualitymentioning

confidence: 99%

Muscle fiber strain rates in the lower leg during ankle dorsi‐/plantarflexion exercise

Hooijmans,

Veeger,

Mazzoli

et al. 2023

NMR in Biomedicine

View full text Add to dashboard Cite

Static quantitative magnetic resonance imaging (MRI) provides readouts of structural changes in diseased muscle, but current approaches lack the ability to fully explain the loss of contractile function. Muscle contractile function can be assessed using various techniques including phase‐contrast MRI (PC‐MRI), where strain rates are quantified. However, current two‐dimensional implementations are limited in capturing the complex motion of contracting muscle in the context of its three‐dimensional (3D) fiber architecture. The MR acquisitions (chemical shift‐encoded water–fat separation scan, spin echo‐echoplanar imaging with diffusion weighting, and two time‐resolved 3D PC‐MRI) wereperformed at 3 T. PC‐MRI acquisitions and performed with and without load at 7.5% of the maximum voluntary dorsiflexion contraction force. Acquisitions (3 T, chemical shift‐encoded water–fat separation scan, spin echo‐echo planar imaging with diffusion weighting, and two time‐resolved 3D PC‐MRI) were performed with and without load at 7.5% of the maximum voluntary dorsiflexion contraction force. Strain rates and diffusion tensors were calculated and combined to obtain strain rates along and perpendicular to the muscle fibers in seven lower leg muscles during the dynamic dorsi‐/plantarflexion movement cycle. To evaluate strain rates along the proximodistal muscle axis, muscles were divided into five equal segments. t‐tests were used to test if cyclic strain rate patterns (amplitude > 0) were present along and perpendicular to the muscle fibers. The effects of proximal‐distal location and load were evaluated using repeated measures ANOVAs. Cyclic temporal strain rate patterns along and perpendicular to the fiber were found in all muscles involved in dorsi‐/plantarflexion movement (p < 0.0017). Strain rates along and perpendicular to the fiber were heterogeneously distributed over the length of most muscles (p < 0.003). Additional loading reduced strain rates of the extensor digitorum longus and gastrocnemius lateralis muscle (p < 0.001). In conclusion, the lower leg muscles involved in cyclic dorsi‐/plantarflexion exercise showed cyclic fiber strain rate patterns with amplitudes that varied between muscles and between the proximodistal segments within the majority of muscles.

show abstract

Section: Study Population and Data Qualitymentioning

confidence: 99%