Contact pattern of the foot during walking in transtibial amputees

MUÑOZ LARROSA, EUGENIA; RIVERAS, MAURICIO; DURE, CAMILA ILEANA; SCHLOTTHAUER, GASTÓN; CATALFAMO FORMENTO, PAOLA

Congreso; XXIV Congreso de Bioingeniería Clínica y XIII Jornadas de Ingeniería Clínica (SABI); 2023

The foot plays a crucial role in walking as it constantly adjusts its contact with the ground to propel the body forward. In able-bodied individuals, the common initial foot contact patterns involves the transition from initial contact at the heel, followed by a rolling motion through the middlefoot and forefoot, and concluding with toe-off. As well, the common final contact pattern follows the same sequences. However, amputees adapt their gait biomechanics to ensure a coordinated and efficient walking pattern. The specific foot contact patterns of individuals with unilateral transtibial amputation have not been studied yet. This research aimed to identify the foot contact patterns of transtibials amputees (initial foot contact pattern and final contact pattern), and compare it with the able-bodied patterns during walking. Based on plantar pressure data collected from eleven participants with transtibial amputation, including their prosthetic foot and intact foot and from the unimpaired feet of nine able-bodied subjects, the initial contact and final contact of seven sub-regions (foot masks) of the foot were measured and sequenced. The results reveal that while a consistent initial contact pattern is observed, the heel is not always the first point of contact for the prosthetic foot. Furthermore, the study highlights that approximately a quarter of all the steps studied presents the forefoot masks, rather than the toes, as the lasts to contact the ground during foot-off. For the prosthetic foot, a change is observed on the medio-lateral movement of the foot roll-over. Movement from the heel is anteriorly and medially and then anteriorly and laterally.