T. Tashiro1, Y. Urabe1, K. Fukui1, N. Maeda1
1Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
Background: Most ankle inversion sprains are mild (Grade 1) (Hosea TM et al., 2000), therefore, athletes want to return to their sports activity as soon as possible. As a result, recurrent ankle sprains occur in athletes who return to sports with ankle instability after trauma. Because of the importance of quick muscle contraction of the peroneus longus (PL) and tibialis anterior (TA) to prevent ankle sprains, many researchers have focused on the muscle function of these muscles. However, no reports on the muscle contractile characteristics of the PL and TA have found.
Purpose: The present investigation aimed to determine the relationship between the frequency of previous ankle sprains and the muscle contractile characteristics of the peroneus longus and tibialis anterior.
Methods: Nineteen male collegiate students (38 legs) participated in this study. Lifetime ankle sprains were recorded for each participant’s leg by way of a self-administered form. For the measurement of muscle contractile characteristics, the tensiomyography (TMG) variables such as delay time (Td), contraction time (Tc), and muscle displacement (Dm) were collected in the PL and TA using a TMG device (TMG-BMC Ltd, Slovenia). Tc (which is obtained by determining the time-lapse from 10% to 90% of Dm) has been related to the speed of force generation, while Td is related to the muscle fiber conduction velocity and Dm to the muscle belly stiffness (Loturco I et al., 2016). Pearson product-moment correlation coefficients were used to assess the relationship between the frequency of previous ankle sprains and the TMG variables of the PL and TA. A significance level was set at 5%.
Results: The overall frequency of previous ankle sprains was 2.3 ± 3.2. The TMG variables were Td 17.2 ± 2.5 ms, Tc 14.9 ± 2.3 ms and Dm 1.3 ± 0.6 mm for PL and Td 21.2 ±1.5 ms, Tc 21.2 ± 3.7 ms and Dm 3.1 ± 1.1 ms for TA. Significant correlations with the frequency of previous ankle sprains were found for Td (r = 0.52, p<0.01) and Tc (r = 0.49, p<0.01) of the PL. In contrast, there were no TMG variables that were significantly correlated in the TA.
Conclusion(s): The present results showed that the more frequent previous ankle sprains, the higher deficits of muscle response and contraction in the PL. The PL is one of the first muscles to contract in response to a sudden ankle inversion stress. Thus, the PL in subjects with previous ankle sprains reduced the ability to quickly generate force during muscle contraction (increase in Td or Tc), which may contribute to the recurrence of ankle sprains. Prospective studies are now required to determine the extent to which altered muscle contractile characteristics influence future injury risk for ankle sprains.
Implications: Clinicians should consider the muscle response and contraction velocity of PL when doing rehabilitation for the ankle evertor in patients with lateral ankle sprains.
Funding, acknowledgements: We have no funding acknowledgment in this study.
Keywords: Ankle sprain, Peroneus longus, Muscle contractile characteristics
Topic: Musculoskeletal: lower limb
Did this work require ethics approval? Yes
Institution: Graduate School of Biomedical and Health Sciences, Hiroshima University, Japan
Committee: Hiroshima University Hospital
Ethics number: E-1905
All authors, affiliations and abstracts have been published as submitted.
