DO THE MORPHOLOGY AND FUNCTION OF PERONEUS LONGUS AFFECT THE MEDIAL LONGITUDINAL ARCH AFTER LATERAL ANKLE SPRAIN?

A. Ishida¹, N. Maeda¹, M. Komiya¹, S. One¹, K. Tsuchida¹, M. Kawai¹, Y. Urabe¹

¹Hiroshima University, Sports Rehabilitation, Graduate School of Biomedical and Health Sciences, Hiroshima, Japan

Background: Lateralankle sprain (LAS) is the most common sports injury and has a high recurrence rate. This high recurrence rate is attributed to instability in foot alignment, especially lower medial longitudinal arch (MLA) (Omer et al., 2005). Prevention of lowering the MLA is important, but research for risk factors of lower MLA after LAS has been insufficient. One of the factors affecting the MLA is the peroneus longus muscle (PL), which thickness and activity during gait are related to the height of the MLA (Murley et al., 2014).Therefore, we focused on morphology and function of the PL after LAS.

Purpose: This study aimed to consider whether morphology and function of the PL affect lowering the MLA after LAS.

Methods: A total of 20 adults (10 males and 10 females) with a history of LAS in one leg participated in this study. As the morphology of the PL,pinnation angle which reflects muscle function was measured using an ultrasound scanner (SONIMAGE MX1, Konica Minolta). As the function of the PL, ankle eversion strength was measured using a hand-held dynamometer. Arch height ratio was calculated by dividing the navicular bone height by foot length. Statistical analysis was performed usingunpaired t-testto compare eachmeasurementbetween theinjured and healthy legs. Additionally, correlations between the arch height ratio and each measurement of the PL were calculated using Pearson’s correlation analysis. The significance level was set at 0.05.

Results: Pennation angle were 9.51±1.46°in injured legs, and 11.18±1.81°in healthy legs (p＜0.05). Ankle eversion strength were 0.88±0.41 N/kg in injured legs, and 0.62±0.23 N/kg in healthy legs (p＜0.05). Arch height ratio were 17.00±1.53％in injured legs, and 17.90±1.33% in healthy legs (p＜0.05). There were no significant correlation between pennation angle, ankle eversion strength and arch height ratio (r=-0.05, r=0.09).

Conclusions: There was no significant correlation between function and morphology of the PL and arch height ratio. The PL is antagonistic to the abductor hallucis (ABH) which supports the MLA, it collapses MLA due to the eversion of the subtalar joint and suppresses the ABH (Choi et al., 2022). In this study, the strength of PL decreased in injured legs. As the strength of PL decreases following LAS, the activity of the ABH increases relatively and the MLA rises (Choi et al., 2022). However,the arch height ratio was decreased in this study. People with a history of LAS show atrophy of the ABH (Mark et al., 2016), it is possible that the participants didn’t show increased activity of the ABH and MLA. Furthermore,it is said the tibialis posterior which maintain the MLA get injured, so this can be contributed to the lowering MLA (Kimura et al., 2017).

Implications: This study implicated that the PL doesn’t affect the lowering MLA after LAS, so we have to focus on the other muscles.

Funding acknowledgements: We have no funding acknowledgement in this study.

Keywords:
lateral ankle sprain
medial longitudinal arch
peroneus longus

Topics:
Sport & sports injuries
Musculoskeletal: lower limb
Musculoskeletal

Did this work require ethics approval? Yes

Institution: hiroshima univertsity

Committee: Ethical Committee for Epidemiology of Hiroshima University

Ethics number: E-2702