Implications of high ankle sprains in college athletes

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High ankle sprains in collegiate athletes differ from lateral or medial ankle sprains in multiple clinically relevant ways. These include loss of sports participation time, mechanism of injury, rates of injury during competition versus practices, and the possible long-term risk of osteoarthritis.

By Timothy C. Mauntel, PhD, ATC; and Zachary Y. Kerr, PhD, MPH

It is well known that ankle sprains are among the most common injuries experienced by collegiate athletes.^1-7 Broadly, ankle sprains can be categorized as lateral ligament complex (inversion) sprains, medial ligament complex (eversion/deltoid ligament) sprains, and distal tibiofibular joint (high ankle/syndesmosis) sprains.^4,5,7,8

Lateral ligament complex ankle sprains are the most commonly reported ankle ligamentous injury (5 injuries per 10,000 athlete exposures)^4-7,9 but are typically rather minor injuries, resulting in a mean of 8.1 days of missed physical activity.⁹ Medial ankle sprains are less common (.8 injuries per 10,000 athlete exposures) but result in slightly longer recovery times (10.7 days).¹⁰ Meanwhile, high ankle sprains are slightly more common than medial ankle sprains (1 injury per 10,000 athlete exposures) and typically result in the longest recovery periods of any ankle sprain (13.9 days).^5,7,11

Nearly half (47.1%) of all high ankle sprains result in more than one week of missed physical activity and one in six (15.8%) collegiate athletes will miss more than three weeks of physical activity following a high ankle sprain injury.¹² Understanding high ankle sprain epidemiology and etiology is essential to help develop prevention interventions aimed at reducing the incidence and severity of these injuries.

Distal tibiofibular anatomy

The distal tibiofibular joint is typically a rather stable joint as a result of its bony and ligamentous supports. The distal tibiofibular joint encompasses the distal tibia and fibula and superior surface of the talus; collectively, these bones form what is commonly referred to as the “ankle mortise.” The ankle mortise is further supported by the anterior- and posterior-inferior tibiofibular ligaments, inter­osseous ligament, and a strong interosseous membrane that runs between the tibia and fibula.^13-15

These many bony and strong soft tissue restraints make the distal tibiofibular joint resistant to many internally generated injurious forces. Thus, sprains to this ligamentous complex in athletes most often result from contact with another player.^12,16,17 Commonly, injury to the distal tibiofibular joint occurs when an individual jumps, steps, or otherwise lands on the foot of another individual, resulting in forced ankle dorsiflexion and foot external rotation.^16,17 A recent study of 25 National Collegiate Athletic Association sports found player contact accounted for 60.4% of high ankle sprain injuries, while noncontact (17.5%) and surface contact (16.9%) mechanisms accounted for much smaller percentages.¹² The findings of this study agree with previous studies that showed the majority of high ankle sprains result from contact with another player.¹⁷

The large percentage of high ankle sprain injuries resulting from player contact is unique to this injury, compared with either lateral or medial ligamentous ankle injuries.^9,10 That means high ankle sprain injury prevention strategies will need to differ to some degree from what has been shown to be effective in reducing lateral or medial ankle sprains.^12,18,19

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Tampa Bay Buccaneers linebacker Lavonte David (number 54) suffered a high ankle sprain on September 24. (Photo courtesy of nflhu.blog.hu.)

The intercollegiate sports with the highest rates of high ankle sprains are men’s football, men’s wrestling, and men’s ice hockey.^12,17,20-22 This is not surprising, as intentional and unintentional player contact is common during these sports. Player contact can result in athletes stepping or landing on another player, which forces the foot into dorsiflexion and external rotation.^16,17

Ankle dorsiflexion and foot external rotation (the most common biomechanical mechanism for high ankle sprain injuries) are required motions during many weightbearing activities, including normal gait.²³ When the ankle is dorsiflexed and the foot is externally rotated, the talus is repeatedly forced superiorly, separating the tibia and fibula,^16,17 which results in stress on the syndesmotic ligaments.⁸ In an athlete with a high ankle sprain, these movements—even if performed during low-impact weightbearing activity—essentially replicate the mechanism of injury with each step or jump. Therefore, injured athletes should avoid weightbearing activity during the early stages of rehabilitation following a high ankle sprain. This extended period of nonweightbearing likely contributes to the significantly longer recovery periods for high ankle sprains relative to either lateral or medial ankle sprains.⁸

Understanding high ankle sprains’ unique mechanism of injury and associated recommendations for a slow-progressing rehabilitation^8,16 will aid clinicians in the prevention and rehabilitation of these injuries.¹²

Frequency of high ankle sprain injuries

High ankle sprains occur at a rate of 1 injury per 10,000 athletic exposures. In a study that examined high ankle sprains across a variety of varsity collegiate sports, male athletes had higher rates of high ankle sprains than female athletes involved in comparable sports (rate ratio = 1.77; 95% CI: 1.28, 2.44).¹² However, this finding may be sport- and/or population-specific, because high ankle sprains are up to 5.36 (95% CI: 1.11, 25.79) times more likely to occur in elite female soccer players than in their male counterparts.²⁴ High ankle sprains are most frequently observed in men’s football (2.4 injuries per 10,000 athlete exposures), men’s wrestling (2.1 injuries per 10,000 athlete exposures), and men’s ice hockey (1.1 injuries per 10,000 athlete exposures).¹² Furthermore, the proportion of high ankle sprains resulting in one week or more of restricted participation was higher in male athletes than female athletes.¹² However, differences in high ankle sprain severity between sexes have not been consistently reported across all studies.⁷

The majority of high ankle sprains occur during competitions (56.7% of all injuries), and there are substantially higher injury rates during competition than practice (rate ratio = 5.79; 95% CI: 4.83, 6.93), across all sports.¹² Within football specifically, this discrepancy is even more pronounced, and high ankle sprain injury rates are nearly 14 times (rate ratio = 13.9; 95% CI: 11.90-16.34) higher during competitions than practices.²⁵ The observation of higher injury rates and counts during competitions as opposed to practices appears unique to high ankle sprain injuries, given that previous work with collegiate athletes from multiple sports found higher injury rates during competitions but higher injury counts during practices.²⁶ Thus, these authors suggested practices may be the best time to incorporate injury prevention strategies (eg, programs targeting proprioception and balance).^9,10,27,28

Proprioception- and balance-focused injury prevention programs have been successful in their own right and may help to mitigate the overall risk of musculoskeletal injuries, namely ankle sprains.^27,28 These programs, however, may not be the most effective means for reducing high ankle sprain risks for collegiate athletes.

New York Giants wide receiver Odell Beckham Jr (13) suffered a high ankle sprain during a preseason game on August 21, but returned to competition at the start of the regular season. (Photo courtesy of newsasylum.com.)

Previous work has suggested integrating targeted injury prevention strategies into competitions will likely be more efficacious for reducing high ankle sprain injury risk than proprioception and balance training programs alone.¹² Examples of such potential prevention strategies include changes to game play rules that minimize player contact (the number-one mechanism of injury)^12,16,17 or implementing the use of mechanical interventions (eg, ankle braces).^12,18,19

Mechanical interventions may reduce the available ranges of motion within the ankle joint and assist with limiting forced dorsiflexion and more likely eversion motions that commonly occur during player contact, thus reducing the risk for high ankle sprain injuries. Although investigations have found the use of mechanical interventions has reduced the incidence of ankle sprain among high school athletes, these studies did not differentiate ankle sprains by type (ie, lateral/medial/high ankle sprain).^18,19 Further research is required to identify the effectiveness of these suggested injury prevention strategies for mitigating high ankle sprain injury risk.

Although there is a need for longitudinal research comparing pre- and postintervention injury rates to determine the effects of such injury prevention strategies, it is also important to incorporate cross-sectional comparisons among samples of student-athletes to understand which characteristics may be risk factors for injury and which may be protective. Descriptive epidemiology helps generate overall estimates of the incidence of high ankle sprain injuries, but a common limitation of such studies is that variability may exist that hasn’t been examined. This variability can occur at the individual level (eg, conditioning level, general health history), team level (eg, types of practice drills and injury prevention programming used), and setting level (eg, mandates and policies per division/state). Thus, future research that further explores the characteristics of study populations at these levels may help to clarify potential positive and negative contributing factors.

Long-term implications

High ankle sprain injuries result in significant time loss from physical activity immediately following injury;^5,7,11,12 however, potentially significant long-term detriments to health following high ankle sprain injuries have also been well documented. Nearly one in 10 (9.8%) of high ankle sprains are recurrent injuries;¹² this is comparable to the recurrence rate of lateral ankle sprains (11.9%) in collegiate athletes.¹⁰ It’s not clear whether one sex is more likely to sustain a recurrent high ankle sprain injury than the other.^12,29,30 If differences in recurrence rates do exist between the sexes, it may be attributable to differences in injury recovery rates, rehabilitation programs, or sport-specific rules that differ between genders (eg, men’s vs women’s lacrosse). Additional work to fully elucidate the potential causes and risk mitigation strategies of high ankle sprain recurrence is warranted.

Furthermore, beyond the initial participation restriction time from sport and the likelihood for increased risk of recurrent injury, the long-term consequences of ankle injury can be debilitating. There is an increased risk of osteoarthritis and post-traumatic osteo­arthritis (PTOA) following acute joint injuries,^31,32 and these findings hold true following ankle sprains, as well.³ One study estimated 79.5% of individuals with ankle OA developed the condition following an acute injury, and specifically 10% of these individuals developed ankle PTOA following an ankle sprain.³³ It is likely that the risk of developing PTOA is even greater following high ankle sprains compared with lateral or medial ankle sprains.

High ankle sprains typically result from higher-energy mechanisms of injury (eg, player contact) than either lateral or medial ankle sprains.^{9,10,12,16,17} Although this has yet to be elucidated, previous
literature examining the rate of PTOA following high-energy ankle injuries (eg, combat-related injuries, plafond fractures) found the incidence of PTOA as high as 57% to 91% following these injuries).^32,34 The short- and long-term consequences of high ankle sprains further underscore the necessity for the development and implementation of targeted high ankle sprain injury prevention and rehabilitation strategies.

Conclusions and take-home points

Seattle Seahawks running back Thomas Rawls suffered a high ankle sprain in the team’s preseason opener on August 13. He returned to competition on September 17. (Photo courtesy of sportspressnw.com.)

High ankle sprain injuries result in significant lost sport participation time, with nearly half of collegiate athletes missing more than seven days of sports participation following a high ankle sprain injury. High ankle sprains most commonly occur following player contact^12,16,17 and occur more frequently during competitions than practices,¹² which are unusual findings compared with many other common injuries observed in collegiate athletics.²⁶ These findings likely require sports medicine professionals to adopt high ankle sprain injury prevention strategies that are different than other common injury prevention strategies and are unique to high ankle sprain prevention.¹² Unlike lateral and medial ankle sprain risks that can be mitigated through intervention programs targeting proprioception and balance,^9,10,27,28 high ankle sprain injury prevention strategies may require mechanical interventions^18,19 or changes to game play rules.¹²

The unique mechanisms and significant long- and short-term consequences of high ankle sprain injuries should make them a priority for sports medicine clinicians so that targeted primary injury prevention strategies and rehabilitation programs may be developed. In addition, as more epidemiological data are published regarding these injuries, clinicians need to advocate for further research that empirically examines associated risk and preventive factors and develops and evaluates current and forthcoming prevention programs.

Timothy C. Mauntel, PhD, ATC, is the research director of the Military Orthopaedics Tracking Injuries and Outcomes Network (MOTION) at the Walter Reed National Military Medical Center in Bethesda, MD. Zachary Y. Kerr, PhD, MPH, is assistant professor in the Department of Exercise and Sport Science and research director for the Center for the Study of Retired Athletes at the University of North Carolina at Chapel Hill.

Note: The views expressed in this article are those of the authors and do not reflect the official policy of the departments of the Army, Navy, or Air Force, the Department of Defense, or the US government.