Viscoelastic properties of a skin-and-muscle compartment in the right and the left hands

Abstract

The aim of this research was to discriminate and categorize isolateral stress-strain characteristics of the musculocutaneous compartment (MCC) using the model of the first dorsal interosseous muscle (FDI) in vivo. In our approach the MCC was progressively isokinetically compressed with a solid vertical bar in 0.25 mm steps, the force and deflection being measured and recorded electronically. The subject maintained a constantly relaxed position. Twenty-two strongly right-handed young males each yielded three data acquisition sequences from each hand. The elastic modulus and the specific energy of deformation were determined both for the total MCC and separately for the skin and muscle moieties. No unilateral pattern of dominance could be interpreted from the analysis of the range of indices. There was a highly variable individual pattern of bilateral dominance with no specific indication or predictability; only one subject yielded a data profile confirming the classical approach to right-hand dominance. As the muscle was relaxed and the integument layers were under minimal cortical influence, we think that the classical theory of primary cortical influence in motor lateralization does not adequately explain our recorded patterns of mechanical response of the MCC under study.