Comparison of Ankle Kinematics between Soft and Semi-Rigid Ankle Orthoses for Field-Sport Activities

Abstract

Purpose of study: Examine ASO (soft) and Malleoloc semi-rigid stirrup (SRS) ankle orthosis designs on ankle kinematics during field-sport movements: sprint, one-legged jump, and 45-degree cut. Participants: 13 competitive Ultimate players who regularly wore an ankle orthosis during physical activity. Methods: ASO or Malleoloc orthosis was randomly assigned to each person. Kinematic data were captured while the participants performed several trials for each movement in a motion analysis laboratory. Participants repeated the protocol with the other orthosis. Results: ASO allowed significantly more plantar-flexion during weight acceptance of the planting foot in cutting (p=0.038). In jumping, the Malleoloc allowed significantly more eversion-inversion range during stance (p=0.048) and eversion-inversion angular velocity from midstance to toe-off (p=0.026). Qualitative data also showed a significant preference for ASO. Conclusion: Hypotheses that ankle inversion and eversion would be greater with the ASO; and plantar-flexion and dorsiflexion would be greater with the Malleoloc were refuted.