Development of a multi-point mapping protocol for myotonometric assessment: a methodological pilot study

The assessment of biomechanical and viscoelastic properties of superficial tissues using myotonometry has gained prominence in clinical and research settings due to its ease of use and ability to provide objective measurements. However, there is a tendency to assess only a single point without considering anatomical or functional variations, and its representativeness for broad regions, such as the lower limbs, remains uncertain. Consequently, we aimed to develop a standardized multi-point protocol for evaluating biomechanical and viscoelastic properties in the lower limbs using myotonometry, test its feasibility and discriminative capacity, and present preliminary exploratory findings. A multi-point myotonometric assessment protocol was developed, where thirty-eight assessment points were identified and described for evaluating the anterior, lateral, posterior, and inferior compartments of the lower limbs. The protocol was applied to both limbs of 13 healthy adult males (age: 32.15 ± 6.50 years). Values were described using mean and standard deviation, and comparisons between consecutive points were tested using the Wilcoxon signed-rank test. Effect sizes were calculated as r = Z/√N. IBM^® SPSS Statistics 20.0 was used with a significant level of 5%. Stiffness values (N/m) showed statistically significant variations between consecutive points, ranging from 136.87 N/m (± 25.55) to 1118.28 N/m (± 357.84), with effect sizes ranging from r = 0.595 to r = 0.874. The statistically significant increase in the proximal-distal and medio-lateral directions, with progressively higher values ​​in the distal and lateral regions, indicates a directional behavior of this property. The proposed multi-point methodology represents an advancement in non-invasive biomechanical assessment. As a methodological development study with preliminary findings, the protocol demonstrates capacity to detect location-dependent variations in stiffness with large effect sizes. Following validation in larger, diverse cohorts, it offers potential for improving diagnosis, therapeutic monitoring, and understanding tissue adaptation mechanisms in clinical and functional contexts.Trial registration: CEPSH/UDESC (CAAE 65601722.5.0000.0118).