Functional and biomechanical effects of a self-locking ankle orthosis versus rigid taping: an observational crossover study

To compare the acute biomechanical and functional effects of rigid taping, the self-locking ankle orthosis (SLAO), and a free condition during two functional jump tests. Forty-five physically active participants completed three randomized conditions (Free, Taping, SLAO) in a single-session crossover design. Functional performance was assessed using the Drop Jump Test and Side Hop Test, while ankle mobility was measured with the Weight-Bearing Lunge Test. Kinematic variables were obtained from 2D video analysis, and temporal parameters (contact time, flight time, jump height, RSI, and power) were recorded using the OptoJump system. Compared with the free condition, both taping and the SLAO significantly reduced ankle dorsiflexion in the Weight-Bearing Lunge Test (p = 0.001) and during landing in the Drop Jump Test (p = 0.001), with greater restriction under taping. In the Drop Jump Test, contact time and maximal knee flexion differed across conditions, but only ankle dorsiflexion at landing showed significant pairwise differences between all conditions (all p < 0.001). In the Side Hop Test, both fixation systems significantly altered all performance-related variables compared with the free condition (all p < 0.001), while no differences were observed between taping and orthosis. The SLAO and ankle taping reduced functional performance compared with the free condition in the Drop Jump and Side Hop tests. Rigid taping induced greater restriction of ankle dorsiflexion, also evident in the Weight-Bearing Lunge Test, whereas the SLAO showed slightly greater sagittal mobility.