Researcher(s)
- Meghna Raj Annasagaram, Biomedical Engineering, University of Delaware
Faculty Mentor(s)
- Stephanie Cone, Biomedical Engineering, University of Delaware
Abstract
Magnetic resonance imaging (MRI) has been used to compare morphology in the triceps surae muscle group (lateral and medial gastrocnemius and soleus muscles) between ages and activity level [1][2]. However, little is known about morphological differences in the triceps surae following different Achilles tendon injuries. To study these injury effects, three subjects (n=3) were examined in this pilot study: one with Achilles tendinopathy, one with Achilles tendon rupture, and one healthy control subject. MRI, shear wave elastography (ultrasound) and functional tests were performed for each subject. MRI scans were then manually segmented to identify the triceps surae, Achilles tendon, and tibia. The STL files were then analyzed in a custom MATLAB code to quantify average cross sectional area (CSA) for each tissue [3]. We found that average CSA for soleus was greatest for the healthy subject, and lowest for the subject with Achilles rupture. When comparing left and right limb differences, the subject with Achilles tendinopathy surprisingly showed the lowest difference, i.e highest symmetry, for all muscles. Meanwhile, the participant with Achilles rupture showed lowest symmetry for the soleus and medial gastrocnemius. Typically, high symmetry between limbs indicates better function and muscle quality. So the subject with Achilles tendinopathy likely had bilateral insults. Since only three subjects were evaluated, it is difficult to tell if these results are attributed to the disease or individual variation. Future studies will increase the analysis to include 15 subjects, allowing for statistical comparison between groups. Future research will also investigate use of shear wave elastography to identify the functional characteristics of the triceps surae. The future goal of this study is to identify which tissues that play a compensatory vs decreased role as a result of these diseases.
[1] Rahemi, H., Nigam, M., Wakeling, J. (2015). The effect of intramuscular fat on skeletal muscle mechanics: implications for the elderly and obese. J. R. Soc. http://dx.doi.org/10.1098/rsif.2015.0365
[2] Pinel, S., Kelp, N., Bugeja, J. (2021). Quantity vs quality: Age-related differences in muscle volume, intramuscular fat, and mechanical properties in the triceps surae. Experimental Gerontology, 156, Article 111594. https://doi.org/10.1016/j.exger.2021.111594
[3] Cone, S. G., Piercy, H. E., & Lambeth, E. P. (2019, October 23). Tissue-specific changes in size and shape of the ligaments and tendons of the porcine knee during post-natal growth. PLOS ONE, 14(10). https://doi.org/10.1371/journal.