Ultrasound Imaging of the Superficial Fascia in the Upper Limb: Arm and Forearm

The superficial fascia has received much attention in recent years due to its important role of compartmentalizing the subcutaneous tissue. Ultrasound (US) imaging, owing to its high definition, provides the possibility of better visualizing and measuring its thickness. The aim of this study was to measure and compare, with US imaging, the thickness of superficial fascia in the arm and forearm in different regions/levels. An observational study has been performed using US imaging to measure superficial fascia thickness in the anterior and posterior regions at different levels in a sample of 30 healthy volunteers. The results for superficial fascia thickness revealed statistically significant differences (p < 0.0001) in the arm between the anterior and posterior regions; in terms of forearm, some statistically significant differences were found between regions/levels. However, in the posterior region/levels of the arm, the superficial fascia was thicker (0.53 +/- 0.10 mm) than in the forearm (0.41 +/- 0.10 mm); regarding the anterior regions/levels, the superficial fascia of the arm (0.40 +/- 0.10 mm) was not statistically different than the forearm (0.40 +/- 0.12 mm). In addition, the intra-rater reliability was good (ICC2,k: 0.88). US helps to visualize and assess the superficial fascia inside the subcutaneous tissue, improving the diagnosis of fascial dysfunction, and one of the Us parameters to reliably assess is the thickness in different regions and levels.