Existe relação entre a resistência mecânica do complexoarticular do mediopé e o movimento de pronação do pédurante a marcha?

Abstract

Increased foot pronation during gait is related to the occurrence of different lower limbinjuries, such as patellofemoral syndrome, patellar tendinosis and hip osteoarthritis. On theother hand, reduced foot pronation is associated to stress fracture of the fifth metatarsal andthe tibia, and iliotibial band syndrome. The magnitude of foot pronation during gait may beinfluenced by the mechanical resistance of the soft tissues at the midfoot complex. This studyinvestigated the relationship between foot pronation during the stance phase of gait and themechanical resistance of the midfoot soft tissues. Thirty-three healthy adults (21 females and12 males) with mean age 26.21 years (SD 5.33), mass 63.23 Kg (SD9.8), and height 169 cm(SD 8.3) participated in this study. We used the Torsimeter to measure the passive mechanicalresistance of the midfoot during forefoot inversion relative to the rearfoot. The maximumstiffness and maximum resistance torque of the midfoot were extracted from the torque-angletime-series. The forefoot, rearfoot and shank angular displacement data during the stancephase of gait were collected with the Qualysis (Oqus 7+) motion capture system synchronizedwith one force plate. The forefoot inversion and dorsiflexion peak relative to the rearfoot, andthe rearfoot eversion relative to the shank were extracted. Correlation analysis wereperformed to investigate the association between the midfoot mechanical resistance toinversion and foot pronation during the stance phase of gait. The midfoot maximumresistance torque was moderately associated with the peak of forefoot inversion (r = 0.38, p =0.029), with the peak of forefoot dorsiflexion (r = -0.35, p = 0.048) and with the rearfooteversion peak (r = -0.45; p = 0.008). There were no associations between foot pronation andmaximal midfoot stiffness (r = 0.34, p = 0.052 for forefoot inversion peak; r = -0.33, p =0.059 for forefoot dorsiflexion peak; e r=0.29, p = 0.093 for rearfoot eversion peak). Theseresults suggest that the midfoot passive mechanical resistance influence the movement of thefoot during the stance phase of gait. In addition, these results may also be explained by thehypothetical effects of foot motion pattern on the midfoot mechanical properties in the longterm, due to repetitive stretching.