Acute effects of different orthoses on lower extremity kinetics and kinematics during running; a musculoskeletal simulation analysis

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.