SLR - May 2018 - Daniel Stewart
Biomechanical Factors Associated with Achilles Tendinopathy and Medial Tibal Stress Syndrome in Runners
Reference: Becker J, James S, Wayner R, Osternig L, Chou L. Biomechanical Factors Associated with Achilles Tendinopathy and Medial Tibial Stress Syndrome in Runners. The American Journal of Sports Medicine. 2017 June 5; 45(11), 2614–2621.
Scientific Literature Review
Reviewed By: Daniel Stewart, DPM
Residency Program: Mercy Hospital, Miami, FL
Podiatric Relevance: Evaluation and treatment of patients with sport-related pathologies, such as Achilles tendinopathy and medial tibial stress syndrome, in the clinical setting is very common for a podiatric physician. As the authors here describe, evaluating symptomatic pronatory forces, addressing biomechanical factors and proper diagnosis in patients who have complaints such as these is a powerful tool that podiatric physicians should use effectively to allow for patients to return to activity.
Methods: Forty-two runners were evaluated in a controlled cross-sectional retrospective laboratory study. Thirteen participants had been diagnosed with Achilles tendinopathy, eight with medial tibial stress syndrome (totaling 21 injured participants) and 21 matched controls based on sex, weekly mileage, age and foot strike pattern. Evaluations included alignment, flexibility and running gait analysis. Differences between the injured participants and the control participants were evaluated for flexibility and alignment, as well as rearfoot kinematics and ground-reaction force metrics.
Results: Injured participants demonstrated higher tibial varum ankles, reduced dorsiflexion range of motion, more rearfoot eversion at heel-off and longer duration of eversion while evaluating running gait when compared to control participants. No differences were noted in the excursion or velocity of eversion when compared to control participants. Regression analysis demonstrates that every 1 percent increase in duration of eversion during stance phase increased the odds of being in the injured group by 1.08.
Conclusions: The authors were able to interpret that, among the various parameters for examination, the duration of pronation through the stance period of gait as a dynamic measurement, with the amount of degrees of dorsiflexion and tibial varum as static measurements, were most reliable as indicators for the likelihood of injury and showed statistical significance when quantified and compared between the control and experimental groups. This is of benefit in the clinical setting to be able to identify and treat at-risk patients before injury may occur. Although, the study did not interpret any kind of treatment options or recommended modalities, it can be inferred that decreasing a patient’s time or position of pronation through stance and at heel-off would be beneficial as a preventative measure. This could include orthotic manipulation, as well as stretching and strengthening exercises that help target a patient’s lack of dorsiflexion or lack of resupination, for example. A number of limitations exist given the nature of the study performed in a motion analysis laboratory rather than a clinical setting. Patients were also allowed to use any shoe they preferred instead of a standardized shoe. Also, no established parameters were used to determine the severity of injury between participants.