LAUSR

PURPOSE The current investigation aimed to examine the effects of different orthotic conditions on the biomechanical mechanisms linked to the aetiology of chronic pathologies using musculoskeletal simulation. METHODS 16 male and 20 females ran over an embedded force plate at 4.0 m/s, in five different conditions (medial, lateral, no-orthoses, semi-custom and off the shelf). Kinematics of the lower extremities were collected using an eight-camera motion capture system and lower extremity joint loading also explored using a musculoskeletal simulation approach. Differences between orthoses conditions were examined using 2 × 2 mixed ANOVA. RESULTS External instantaneous load rate was significantly reduced in the off the shelf orthoses (male = 1290.60 and female = 1567.10 N/kg/s), compared to the medial (male = 1480.45 and female = 1767.05 N/kg/s) and semi-custom (male = 1552.99 and female = 1704.37 N/kg/s) conditions. In addition, peak patellofemoral stress was significantly lower in the off the shelf orthoses (male = 68.55 and female = 94.91 KPa/kg) compared to the lateral condition (male = 70.49 and female = 103.22 KPa/kg). Finally, peak eversion angles were significantly attenuated in the medial orthoses (male = -6.61 and female = -7.72 deg) compared to the lateral (male = -9.61 and female = -10.32 deg), no-orthoses (male = -8.22 and female = -10.10 deg), semi-custom (male = -8.25 and female = -9.49 deg) and off the shelf (male = -7.54 and female = -8.85 deg) conditions. CONCLUSIONS The current investigation shows that different orthotic devices⁄ configurations may provide distinct benefits in terms of their effectiveness in attenuating the biomechanical parameters linked to the aetiology of chronic running injuries.