Ankle strategies for step-aside movement during quiet standing

The mediolateral ankle strategy plays a crucial role in providing ankle stability in ground obstacle-avoidance behavior. This is achieved by changing basic walking patterns according to the characteristics of the obstacle. In daily life, it is more common to use step-aside movement (i.e., dodging step) for collision avoidance rather than side-stepping (i.e., widening standing base) when encountering an approaching pedestrian or bicycle. While studies have been conducted on the mediolateral ankle strategy contribution in obstacle avoidance using side-stepping, knowledge of step-aside movement is still inadequate. Therefore, we conducted an electromyography (EMG) analysis on the tibialis anterior (TA), peroneus longus (PL), and soleus (SOL) muscles, as well as measured center of pressure (CoP) displacement, and vertical ground reaction force (vGRF) of the standing leg, in order to understand the role of ankle muscles in step-aside movement during quiet standing. Fifteen healthy young men repeated twelve step-aside movements in both left and right directions. A Bayesian one-sample t-test was used to determine the sufficient step and participant counts. Multiple linear regression analysis was used to investigate the correlation between the muscle activity and CoP displacement or vGRF. The regression coefficients (β) of the left push phase and the right loading phase were tested against zero using a Bayesian one-sample t-test to identify the correlation between independent and dependent variables. We used the one-dimensional statistical parametric mapping (SPM1d) method to analyze the differences between and within the groups of EMG data based on the continuous time series. The results showed that the PL displayed a substantial contribution to the mediolateral ankle strategy during the push phase of step-aside movement, and also contributed to maintaining ankle stability during the loading phase. This suggested that screening for PL weakness and providing appropriate interventions and/or training approaches is especially critical for populations with walking stability problems.

Foot Muscle Strengthening and Lower Limb Injury Prevention

Background and objectives: The active and passive structures of the foot act in unison to not only be compliant enough to assist in ground reaction force attenuation but also resist deformation to provide a stable base of support. A foot that is unable to adjust to the imposed demands during high-intensity sporting activities may alter the moments and forces acting on the joints, increasing the risk of non-contact anterior cruciate ligament ruptures (ACLR) and lateral ankle sprains (LAS). Prophylactic strengthening programs are often used to reduce the risk of these injuries, but at present, very few prophylactic programs include foot-specific strengthening strategies. The aim of this theoretical review is to ascertain the prophylactic role strengthening muscles acting on the foot may have on ACLR and LAS injury risk. Methods: Literature relating to risk factors associated with ACLR and LAS injury and the anatomy and biomechanics of normal foot function was searched. In addition, ACLR and LAS injury prevention programs were also sought. A theoretical, narrative approach was followed to synthesize the information gathered from the articles. Results: The foot segments are governed by the congruity of the articulations and the activity of the foot muscles. As such, there is a coupling effect between shank, calcaneus, midfoot, and hallux movement which play a role in both ACLR and LAS injury risk. Conclusions: Strengthening the muscles acting on the foot may have a significant impact on ACLR and LAS injury risk.

Athletic Training Service Characteristics for Patients With Ankle Sprains Sustained During High School Athletics

CONTEXT

Limited information exists on the amount and type of care provided by athletic trainers (ATs) treating athletes who sustained ankle sprains in the high school setting.

OBJECTIVE

To describe AT services provided for patients with ankle sprains injured in high school athletics.

DESIGN

Descriptive epidemiology study.

SETTING

Athletic training facility (ATF) visits and AT services collected from 147 high schools in 26 states.

PATIENTS OR OTHER PARTICIPANTS

High school student-athletes participating in 13 boys' and 14 girls' sports who sustained a diagnosed ankle sprain during the 2011-2012 through 2013-2014 academic years. The ATs documented 3213 ankle sprains.

MAIN OUTCOME MEASURE(S)

Number of ATF visits and individual AT services and mean ATF visits (per injury) and AT services (per injury) were calculated by sport and for time-loss injuries (participation-restriction time of at least 24 hours) and non-time-loss injuries (participation-restriction time <24 hours).

RESULTS

During the 3-year period, 19 925 ATF visits were reported, with an average of 6 (interquartile range = 1-7) ATF visits per ankle sprain. Most ATF visits were for non-time-loss injuries (65.1%). Football accounted for the largest proportions of ankle sprains (27.3%) and ATF visits (35.0%). In total, 71 404 AT services were provided for ankle sprains. Therapeutic activities or exercise were the most common AT services (47.4%), followed by neuromuscular reeducation (16.6%), strapping (14.2%), and modalities (11.5%). An average of 22 (interquartile range = 4-28) AT services were reported per ankle sprain. The average number of AT services per injury was higher among patients with time-loss than non-time-loss injuries (35 versus 19; P < .001).

CONCLUSIONS

The ATs provided a variety of services to treat high school athletes who had sustained ankle sprains, including therapeutic exercises and neuromuscular reeducation, which were supported by research. However, ATs should consider using manual therapy (use supported by grade B evidence) and therapeutic exercise more (use supported by grade A evidence).