The influence of heel height on frontal plane ankle biomechanics: implications for lateral ankle sprains.

Background: Wearing high heel shoes is thought to increase an individual's likelihood of experiencing a lateral ankle sprain. The purpose of this study was to evaluate the influence of heel height on frontal plane kinematics, kinetics, and electromyographic (EMG) activity of the ankle joint during walking.

Methods: Eighteen healthy women participated. Three-dimensional kinematics, ground reaction forces, and EMG signals of the tibialis anterior (TA) and peroneus longus (PL) were recorded as subjects ambulated in high (9.5~cm) and low (1.3~cm) heel shoes at a self-selected walking velocity. Peak ankle plantarflexion, peak ankle inversion angle, and the peak ankle inversion moment during the stance phase of gait were evaluated. The EMG variables of interest consisted of the normalized average signal amplitude of the TA and PL during the first 50% of the stance phase. Paired t-tests were used to assess differences between the two shoe conditions.

Results: When compared to the low heel condition, wearing high heels resulted in significantly greater peak ankle plantarflexion and inversion angles (p < 0.001). In addition, the peak inversion moment and PL muscle activation was found to be significantly higher in the high heel condition (p < 0.001). No difference in TA muscle activity was found between shoe conditions (p = 0.30).

Conclusion: The plantarflexed and inverted posture when wearing high heels may increase an individual's risk for experiencing a lateral ankle sprain.

Clinical Relevance: Data obtained from this investigation highlights the need for increased awareness and proper education related to the wearing of high heel shoes.