ABSTRACT
INTRODUCTION: A sprain describes an excessive amount of force or strain on a ligament, which may or may not lead to its rupture. Orthoses are among the most common modalities prescribed as a conservative treatment for ankle instability and sprain. OBJECTIVE: We aimed to analyse the effect of neoprene orthosis on the balance and functionality of healthy individuals and volunteers with lateral ankle sprains METHODS: We evaluated 12 healthy volunteers (control group) and 12 volunteers diagnosed with a sprain and/or instability (patient group). A total of 14 men and 10 women participated in the study, with an average age of 26.15 (± 4.40) years. The volunteers' tasks consisted of performing vertical bipodal and unipodal jumps on a force platform, which were recorded in a video from the lateral view of the lower limb for posterior evaluation of the knee and ankle angles. Mann-Whitney and Wilcoxon tests were used for comparisons, considering p < 0.05 level of significance. RESULTS: The control group presented a decrease in ground reaction force when using Orthosis during the bipodal jump (p < 0.05). A decrease in anteroposterior force displacement was also observed in the left unipodal jump (p < 0.01). The patient group presented an increase in force and moment of medial-lateral displacement for both bipodal (p < 0.02) and left unipodal jumps with Orthosis (p < 0.02). A kinematic analysis showed that the control group presented the smallest knee flexion angle (p < 0.01), while the patient group presented the smallest dorsiflexion ankle angle in the bipodal jump when using orthosis (p < 0.01). CONCLUSION: We concluded that orthosis had influence on individuals' balance and joint angles. In healthy individuals presented better balance with and without orthosis and greater flexion with orthosis in the bipodal jump, regarding to the patient group presented smaller oscillations in the unipodal jump with orthosis and showed smaller knee flexion and ankle dorsiflexion.