Sports prevention experts are always looking for new ways to keep athletes from getting injured. Many studies focus on how to run correctly or how to prevent overuse injuries, but few examine a person’s risk for injury before they begin a running regimen. Risk factor screenings do just that.
Risk factor screenings help physicians determine how likely it is that a person will develop a certain condition. A physical exam as well as an analysis of a person’s family history can help spot trends and implement prevention techniques to lessen a person’s overall risk.
Physicians rely on these risk assessments to diagnose the likelihood of conditions like heart disease, diabetes and stroke, but they can also be used to understand potential foot and ankle conditions. One such condition that is often screened for is exertional medial tibial pain (EMTP), which is characterized by exertional pain along the posteromedial border of the middle and distal thirds of the tibia. Recently, a team of physical education researchers decided to better improve the accuracy of the EMTP risk assessment by tracking 96 female runners over the course of two years.
The Study
Researchers believe that accurate risk factor screening is an important element of injury prevention for runners. To evaluate the effect of muscle fatigue for those runners at risk for EMTP, researchers had the study participants complete an online questionnaire each week and a retrospective survey every three months to categorize and track their leg pain. Participants were asked to rate their pre- and post-run pain, and an medical doctor evaluated the women at the end of the study to determine which participants suffered from EMTP.
After analyzing the data, researchers found:
- 21 participants were diagnosed with EMTP at the conclusion of the study.
- In a non-fatigued (pre-run) state, only increased range of motion in the transverse plane (ROMT) of the hip could be identified as a significant risk factor.
- In a fatigued state, increased ROMT of the hip and pelvis during landing and increased ROMT of the thorax during pushoff could be identified as risk factors.
Based on their findings, researchers concluded that adding a muscle fatigue protocol during the risk factor screening test could help determine which leg is more susceptible to EMTP risk and provide a more accurate likelihood that a person will develop EMTP.
Physical Therapist Andy Masis Comments
Every year, approximately 65-80% of runners will incur an injury (McDougall 2009) which makes this a serious problem for the health care community. Ground reaction forces (GFR) or the impact generated by the foot striking the ground, is a predictable and highly repetitive stress that can exceed five times body weight.
Many runners lack appropriate strength and integrated stability of their glutes and adductors as this study indicates, which makes it even more difficult for them to disperse the impact forces generated by the foot striking the ground.
What this study does not take into account is running style. Whether a runner is a heel-striker or a non-heel striker (barefoot running style) makes a big difference in the amount of force generated, and the amount of muscles that are available to disperse these forces. Current research seems to indicate that non-heel strikers (barefoot runners) demonstrate increased activation of medial and lateral ankle stabilizers of the foot and ankle, decreased impact at foot strike, and decreased incidence of such overuse injuries as Plantar Fasciitis and Medial Tibial Stress Syndrome (Squadrone, et al. 2005 / Divert C et al. 2009).
While strength and stability of lumbar and pelvic stabilizers is always important for a runner, running style should be an important consideration for those runners suffering from overuse lower extremity injuries.
It is important to remember that any change in biomechanics should be slow and progressive.