A three-experiment examination of iliotibial band strain characteristics during different conditions using musculoskeletal simulation

Abstract

Iliotibial band syndrome (ITBS) is a common chronic pathology mediated via excessive Iliotibial band (ITB) strain. The purpose using a three-experiment approach is to provide insight into the differences in strain between different athletic movements, the incidence of ITBS in females, the efficacy of different prophylactic modalities for ITBS and also the kinematic parameters associated with ITB strain. Experiment 1 examined male and female athletes performing run, 45° cut and one-legged hop movements, experiment 2 observed males and females, whilst running in five different orthotic conditions and experiment 3 examined males and females riding a cycle ergometer at 70, 80 and 90 RPM whilst in prophylactic knee brace and no-brace conditions. In each experiment, kinematics were obtained using a motion capture system and ITB strain was measured using a musculoskeletal simulation approach. In experiment 1, ITB strain was greater in the run (male = 3.87% and female = 4.37%; P < 0.001) and cut (male = 3.12% and female = 4.06%; P < 0.001) movements compared to hop (male = 0.87% and female = 1.54%). Experiment 2 showed that females exhibited increased ITB strain (male = 6.34% and female = 8.91%; P < 0.05) and ITB strain velocity (male = 57.17%/s and female = 77.41%/s; P < 0.05) and also in females that ITB strain velocity was greater (P ≤ 0.01) in lateral (80.22%/s) and no-orthotic (83.01%/s) conditions compared to medial (72.58%/s) and off the shelf orthoses (74.52%/s). The regression analyses across movements showed that ITB strain was predicted by sagittal and coronal plane mechanics at the hip (R2 = 0.15–0.30; P < 0.05) and sagittal, coronal and transverse plane kinematics at the knee joint (R2 = 0.15–0.22; P < 0.05). Further insight is provided into differences in ITB strain across functional athletic movements, the increased incidence of ITBS in females and the parameters linked most strongly with ITB strain during different movements is provided; whilst also highlighting the prophylactic efficacy of medial and off the shelf orthoses in female runners.