Comparison of Kinematic Variables of Ankle Joint in Athletes with Functional Ankle ‎Instability, Coper and healthy During Running

Ankle sprain is one of the most common sports injuries. While the effects of static constraints in stabilizing the ankle joint are relatively well understood, those of dynamic constraints are less clear and require further investigation. The purpose of this study was to compare kinematic variables of ankle joint in athletes with functional ankle instability, Coper and healthy during running.

75 athletes were randomly divided into 3 groups of functional ankle instability (age: 24.04±4.42 years, height: 182.20±6.63 cm, weight: 73.96±7.06 kg), Coper (age: 25.56±4.96 years, height: 185.44±6.97 cm, weight: 77.44±7.03 kg) and healthy (age: 26.40±4.71 years, height: 183.72±6.52 cm, weight: 74.26±6.56 kg). Subjects were asked to run on a treadmill at a speed of 10 km / h for 30 seconds. Kinematic data were recorded using a 3D optic track camera and then used with MATLAB to construct a dynamic model and analyze the data. To compare three groups, one-way analysis of variance test with a significance level of 0.05 was used.

The present study showed that there was a significant difference in dorsiflexion and ankle inversion between the three groups at the moment of initial contact (P≤0/05). Also, the results of the Toki follow-up test showed that there was no significant difference between the Coper and healthy groups in the dorsiflexion and inversion (P≥0/05).

The results showed that functional ankle instability group had less dorsiflexion and more inversion than Coper and healthy group at the moment of initial contact. There was also no significant difference between Coper and healthy groups in dorsiflexion and inversion. Therefore, athletes' strategy of functional ankle instability has altered and the focus of rehabilitation protocols should be on the kinematics of ankle joint in functional activities to prevent recurrent sprain.