Running is a common form of exercise enjoyed throughout the world. Unfortunately, it poses a significant risk of injury, as up to 70% of runners suffer an overuse injury within a one-year period. Previous research indicates that three overarching factors contribute to overuse injuries in running – dosage, morphology, and movement patterns;​ however, the threshold of these three factors combining to result in injury is specific to each athlete, and not well understood.

To aid future research of overuse injuries, we conducted two studies using three different measurement modalities. In the first study, we used Inertial Measurement Units (IMUs) to monitor gait features of participants running on a treadmill. Using statistical parametric mapping of IMU signals, the system detected changes in strike pattern, stride length, bouncing gait, and genu valgus gait. With further validation and refinement, this system would allow for monitoring of these gait features in the wild, giving researchers greater insight into the development of overuse injuries.

The second study was a pilot study, in which we investigated motion of the tibia and relative motion of the talus and calcaneus with respect to the tibia during a hopping motion. We found that internal rotation of the talus after impact leads the internal rotation of the tibia. This grants plausibility to the theory of tibiotalar coupling – that internal rotation of the tibia is driven by that of the talus. After approximately 20% of stance, the talus moves into external rotation with respect to the tibia, and we hypothesize that it acts as a buffer to allow rotational independence between the rearfoot and tibia. Additionally, this study highlighted the inherent inter-subject variability in biomechanics studies. We have shown that there is benefit and necessity in subject-specific analysis over population-wide conclusions in biomechanics.

Finally, we discuss the implications of both studies to the future of overuse injury research. The research presented is a first step toward more comprehensive studies into overuse injury etiology. Using the approaches described, researchers may be able to use a combination of measurement modalities to encompass dosage, morphology, and movement patterns in a large-scale, prospective overuse injury study.