- Open Access
Understanding acute ankle ligamentous sprain injury in sports
BMC Sports Science, Medicine and Rehabilitation volume 1, Article number: 14 (2009)
This paper summarizes the current understanding on acute ankle sprain injury, which is the most common acute sport trauma, accounting for about 14% of all sport-related injuries. Among, 80% are ligamentous sprains caused by explosive inversion or supination. The injury motion often happens at the subtalar joint and tears the anterior talofibular ligament (ATFL) which possesses the lowest ultimate load among the lateral ligaments at the ankle. For extrinsic risk factors to ankle sprain injury, prescribing orthosis decreases the risk while increased exercise intensity in soccer raises the risk. For intrinsic factors, a foot size with increased width, an increased ankle eversion to inversion strength, plantarflexion strength and ratio between dorsiflexion and plantarflexion strength, and limb dominance could increase the ankle sprain injury risk. Players with a previous sprain history, players wearing shoes with air cells, players who do not stretch before exercising, players with inferior single leg balance, and overweight players are 4.9, 4.3, 2.6, 2.4 and 3.9 times more likely to sustain an ankle sprain injury. The aetiology of most ankle sprain injuries is incorrect foot positioning at landing – a medially-deviated vertical ground reaction force causes an explosive supination or inversion moment at the subtalar joint in a short time (about 50 ms). Another aetiology is the delayed reaction time of the peroneal muscles at the lateral aspect of the ankle (60–90 ms). The failure supination or inversion torque is about 41–45 Nm to cause ligamentous rupture in simulated spraining tests on cadaver. A previous case report revealed that the ankle joint reached 48 degrees inversion and 10 degrees internal rotation during an accidental grade I ankle ligamentous sprain injury during a dynamic cutting trial in laboratory. Diagnosis techniques and grading systems vary, but the management of ankle ligamentous sprain injury is mainly conservative. Immobilization should not be used as it results in joint stiffness, muscle atrophy and loss of proprioception. Traditional Chinese medicine such as herbs, massage and acupuncture were well applied in China in managing sports injuries, and was reported to be effective in relieving pain, reducing swelling and edema, and restoring normal ankle function. Finally, the best practice of sports medicine would be to prevent the injury. Different previous approaches, including designing prophylactice devices, introducing functional interventions, as well as change of games rules were highlighted. This paper allows the readers to catch up with the previous researches on ankle sprain injury, and facilitate the future research idea on sport-related ankle sprain injury.
Ankle ligamentous sprain injury is the most common single type of acute sport trauma . Over the years, various preventive strategies have been implemented, however, a recent epidemiology revealed that ankle sprain injury still dominated in sport injury, as it accounted for 14% of all attendance in an accident and emergency department . In the recent decade, the growing orthopaedic biomechanics techniques have enhanced a better understanding of injury mechanism, and the subsequent research in sports injury prevention and management . This paper summarizes the current understanding in acute ankle ligementous sprain injury in sports, which facilitates the future research on ankle sprain prevention. Literature search of MEDLINE (from 1966) and PubMed (from 1950) was conducted in May 2008. The search keyword string was "ankle AND (injury OR injuries OR sprain)", which appeared in the title, abstract or keyword fields. The title and abstract of each entry was read to identify and exclude unrelated articles. Articles not written in English were also excluded. The information of the papers was summarized into the sub-topics in this article in the following paragraphs to form the current understanding on acute ankle ligamentous sprain injury in sports.
Sports participation and sports injury
All around the world, medical doctors and sports scientists were actively promoting regular physical exercises to gain health benefits and to prevent cardiovascular related disease . People nowadays are more eager in participating in sports and exercises for personal interest, leisure, relaxation, health and fitness purposes. In Hong Kong, according to the annual survey of sports participation conducted by the Hong Kong Sports Institute , people in general were becoming more active in sports participation from 1996 to 2001. The increasing trend was found in youngster and elderly  as well as working population . The increasing sports participation was also reflected by the number of participants in the annual marathon race. There were only 1,000 participants in the first marathon race in 1997. The number of participants increased every year, and reached 10,000 in 2001. The number of participants kept increasing in recent years and has dramatically increased to 50,000 in 2008 . Most of the participants were recreational athletes, indicating a mass participation of sports among the population.
However, in contrary to the promotion of the health benefits from sports participation, sports often cause injuries . A study in Sweden  reported that 17% of the 3,341 acute visits to a clinic due to accidents in a one-year prospective study were from sports. It was comparable to home accident (26%), work accident (19%) and was much higher than traffic accident (7%). In United Kingdom, there were 7.1% of the 2,432 new patients attending accident and emergency department in a 10-day period sustained trauma from sports . In North Ireland, for adolescent of age 11–18 who actively participated in sports, as much as 51% of the attendees sustained sports injuries . When the sports participation rate became high, the exposure to potential injury increased and thus the high incidence of sport injury .
Problem and outcome of sports injury
Sports injuries resulted in pain , loss of playing or working time , as well as medical expenditure . Severe ankle injuries also occasionally resulted in bone fractures , functional instability , decreased muscle strength , inferior proprioception , limited mobility , disability , permanent cease or retirement of sports participation . Without adequate treatment and rehabilitation, sports injuries may also cause significant susceptibility in developing osteoarthritis  and other kinds of permanent sequalae . For world-class and commercial sports teams, absence of key players due to unexpected injuries may result in defeats in major games and huge economic loss.
Prevalence and patterns of ankle sprain injury
Previous studies reported that injury to the knee was the most common and injury to the ankle the next [9, 26]. Ankle was the most common injured body site in 24 of 70 included sports . Ankle ligament sprain were also reported to be the most common injury for college athletics in the United States . In Hong Kong, a survey on 2,293 patients attending a sports injury clinic reported that the knee (27.3–50.5%) and the ankle (16.8–24.7%) were the most common sites of injury in soccer, basketball, volleyball and long-distance running sports . In marathon racing, another study on 580 runners in a marathon race reported that 33.9% of the injuries were to the knee and 20.9% were to the ankle . Among ankle injuries, ankle sprain injury accounts for more than 80%, and is also the most common single type of sport-related trauma among all body sites and types [29–31]. Among ankle sprain injuries, 77% were lateral sprains  and 73% involved isolated rupture or tear to the anterior talofibular ligament [32, 33]. A local survey conducted on 380 athletes with 563 sprained ankles reported that the majority of these injured athletes were pursuing running and jogging activities (25%), racquet sports (20%), ball games (19%) and soccer (14%) . The residual problem included pain (30.2%), instability (20.4%), crepitus (18.3%), weakness (16.5%), stiffness (14.6%) and swelling (13.9%).
Ankle anatomy and biomechanics
In human anatomy, the ankle joint is where the foot and the leg segments meet. It comprises of three major articulations: the talocrural joint, the subtalar joint, and the distal tibiofibular syndesmosis . The talocrural joint is also termed the tibiotalar joint or the mortise joint, and is formed by the articulation of the dome of talus, the tibial plafond, the medial malleolus and the lateral malleolus. This joint, in isolation, behaves rather like a hinge joint that allows mainly plantarflexion and dorsiflexion. The fibula extends further to the lateral malleous than the tibia does to the medial malleolus, thus creating a block to eversion . Such body feature mainly allows larger range of inversion than eversion, thus, inversion sprains are more common than eversion ones .
The talocrural joint is supported by several main ligaments, namely the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL) and the posterior talofibular ligament (PTFL) at the lateral aspect, and the deltoid ligament in the medial aspect of the ankle . Among the lateral ligaments, the ATFL is the weakest as it has the lowest ultimate load, approximately 138.9N, which is about half of that of PTFL, that is, 261.2N, and one-third of that of CFL, that is, 345.7N . These values were obtained from mechanical test on ligaments of fresh human ankles. ATFL is approximately 20–25 mm long, 7–10 mm wide and 2 mm thick [39, 40]. It originates from the anterior-inferior border of the fibular and inserts to the neck of the talus . It prevents anterior displacement and internal rotation of the talus, especially when the talocrural joint is plantarflexed [41–43]. Due to its low ultimate load and the anatomical positions of origins and insertions, the ATFL is most commonly injured in a lateral ankle sprain .
The subtalar joint is formed by the articulation between the bottom of the talus and the calcaneus . It consists of two separate joint cavities. First, the anterior subtalar joint, or also termed the talocalcaneonavicular joint, is formed from the head of the talus, the anterior-superior facets, the sustentaculum tali of the calcaneus, and the concave proximal surface of the tarsal navicular . Second, the posterior subtalar joint is formed between the inferior posterior facet of the talus and the superior posterior facet of the calcaneus . The anterior and posterior subtalar joints behave like a single ball-and-socket joint and share a common oblique axis of rotation , which averages a 42-degree upward tilt and a 23-degree medial angulation from the perpendicular axes of the foot . This articulation allows inversion and eversion, or supination and pronation as described as a triplanar motion . The subtalar joint is supported by three groups of ligaments, namely the deep ligaments, the peripheral ligaments, and the retinacula . Together these ligament groups stabilize the subtalar joint and form a barrier between the anterior and posterior joint capsules .
The distal tibiofibular syndesmosis is formed by the articulation between the distal tibia and fibula . The joint is mainly stabilized by a thick interosseous membrane, with the anterior and posterior inferior tibiofibular ligaments, to form the stable roof for the mortise of the talocrural joint . This joint allows limited translation and rotation during talocrural dorsiflexion and plantarflexion to accommodate the asymmetric talus while maintaining congruency . Injury to this ligament group is rare, and is often termed ankle syndesmosis injury , syndesmotic ankle sprain , or high ankle sprain .
Risk factors for ankle sprain injury
Risk factors were commonly classified as extrinsic or intrinsic . Extrinsic risk factors are those that come from outside of the body, while intrinsic factors are those from within the body. In 1997, Barker, Beynnon and Renstrom  did a comprehensive review on the ankle injury risk factors in sports as reported by about 20 prospective studies. For extrinsic factors, although they found some discrepancies among the included studies, they generally reported that the prescription of orthosis, but not high-top shoes, could help decreasing the risk of sustaining ankle sprain injury in players with previous sprain history. Increased exercise intensity in soccer raised the injury risk, but the player positions in soccer and basketball did not cause any difference. For intrinsic factors, they reported that a previous sprain history, a foot size with increased width, an increased ankle eversion to inversion strength, plantarflexion strength and ratio between dorsiflexion and plantarflexion strength, and limb dominance could increase the ankle sprain injury risk. The foot type, indication of ankle instability, and high general joint laxity were identified not to be risk factors. In 2002, Beynnon, Murphy and Alosa  conducted another comprehensive literature review and reported a consensus that gender, general joint laxity and foot type were not risk factors for ankle sprain injury. In 2007, Morrison and Kaminski  suggested that the cavovarus deformity, increased foot width, and increased calcaneal eversion range of motion were related to the occurrence of lateral ankle sprain injury. However, significant discrepancies were found with regard to whether or not height, weight, limb dominance, ankle joint laxity, anatomical alignment, muscle strength, muscle reaction time, and postural sway are risk factors for ankle sprain injury.
Some recent studies reported that players with a history of ankle sprain, players wearing shoes with air cells in the heel, and players who did not stretch before exercising were 4.9, 4.3 and 2.6 times more likely to sustain an ankle sprain injury . People with inferior single leg balance  and overweight  were 2.4 and 3.9 times more likely to have sprain injury respectively. Reduced ankle dorsiflexion range , the use of artificial turf for soccer  and having a posteriorly positioned fibula  were also reported as risk factors. In 2005, Willems and coworkers  investigated some dynamic risk factors during gait in related to ankle sprain injury. They reported that for subjects who were at risk of sustaining an inversion sprain, a laterally situated center of plantar pressure was found at initial contact during the stance phase. The same research group also reported the intrinsic risk factors for inversion ankle sprain for male and female. For male, a slower running speed, less cardiorespiratory endurance, less balance ability, decreased dorsiflexion muscle strength, decreased dorsiflexion range of motion, less coordination ability, and faster reaction of the tibialis anterior and gastrocnemius muscles were the significant risk factors . For female, a less accurate passive joint inversion position sense, a higher extension range of motion at the first metatarsophalangeal joint, and a less coordination of postural control were the major risk factors . However, we have to be aware that these risk factors are only some correlations with ankle ligament sprain injury. They may not be the direct cause, or the aetiology of ankle ligament sprain.
Aetiology of ankle supination sprain injury
Fuller  suggested that most ankle sprain injuries were caused by an increased supination moment at subtalar joint, which was often a result of the position and the magnitude of the vertically projected ground reaction force at initial foot contact. If the center of plantar pressure deviated medially to the subtalar joint axis, a greater moment arm along the subtalar joint axis was achieved and thus the subsequent increased supination moment to initiate sudden explosive ankle supination. Wright and coworkers  conducted a computational forward dynamic simulation study and reported that increased touch down plantarflexion caused increased ankle sprain occurrences. When a foot was plantarflexed during touch down, the contact to the ground was made with the forefoot, thus increased the moment arm among the subtalar joint axis and also the resultant joint torque to cause sudden explosive twisting motion and ankle sprain injury. Therefore, foot positioning during touch down was identified as an aetiology of ankle sprain injury. This also supported the suggestion that ankle taping or bracing corrected ankle joint positioning at landing rather than provided mechanical support to the ankle joint [68–70].
Another aetiology of ankle sprain injury is the delayed reaction time of the peroneal muscles at the lateral aspect of the ankle. Ashton-Miller and coworkers  suggested that an ankle sprain injury occured in 40 milliseconds (ms), as the vertical ground reaction force peaked at about 40 ms when landing from a jump . At the lateral aspect of the human ankle, the peroneal muscles, including the peroneal longus and peroneal brevis, function to initiate ankle pronation which opposes the ankle supination motion . Numerous research groups reported the reaction time of the peroneal muscles to be 50 ms or more. For instance, in sudden inversion tests with healthy subjects in an initial standing position, the peroneal muscle reaction time was reported to be 57–58 ms , 57–60 ms , 58 ms , 65–69 ms , 67–69 ms  and 69 ms . For patients with ankle instability, the peroneal reaction time is longer – it was reported to be 82–84 ms  and 85 ms . In a sudden inversion in a dynamic walking trial, the reaction time is also longer, as reported to be about 74 ms . After the reflex response, the eversion torque was generated at 135 ms  and the subsequent active eversion was achieved at about 176 ms . Therefore, it is postulated that the human reflex response is not fast enough to accommodate the sudden explosive motion in a sprain injury.
Mechanism and biomechanics of ankle supination sprain injury
Understanding the injury mechanism is very important for the research of injury prevention [81, 82]. In ankle supination sprain, there is ankle inversion plus an internal twisting of the foot , and plantarflexion with the subtalar joint adducting and inverting . Sometimes there is also an external rotation of the lower leg in respect to the ankle joint . Stormont and coworkers  suggested that most ankle sprains occurred during systematic loading and unloading, but not while the ankle was fully loaded due to articular restraints. When the foot is in plantarflexion, the anterior talofibular ligament is often injured; when the foot is in dorsiflexion, the calcaneofibular ligament is often injured . In soccer, most ankle sprains were sustained during player contact (59%), but during non-contact situations for goalkeepers (79%) . In a recent study to analyze the ankle supination sprain injury with video, Andersen and coworkers  reported that there were two major mechanisms: (1) impact by opponent on the medial aspect of the leg just before or at foot strike, resulting in a laterally directed force causing the player to land with the ankle in a vulnerable inverted position; (2) forced plantar flexion when the injured player hit the opponent's foot when attempting to shoot or clear the ball. Most of these mechanisms finally led to the rupture of the anterior talofibular ligament, as this ligament often sustained higher strain and strain rate values than the other ligaments at the lateral ankle .
The biomechanics of ankle supination sprain injury was seldom reported in the literature, as it is practically impossible and also unethical to conduct systematic dynamic ankle sprain test in the laboratory. Previous mechanism study only reported qualitative information. For quantitative evaluation, different research groups managed to conduct cadaver study to understand the ankle biomechanics during simulated spraining tests. In static cadaver study, Markolf, Schmalzried and Ferkel reported that a 41–45 Nm external rotatory torque would cause ankle failure , as defined by a major drop-off of the torque as the foot continued to rotate, indicating a bony fracture or ligamentous rupture. In dynamic cadaver study, Self, Harris and Greenwald  studied the ankle biomechanics during a drop test with cadaver ankles, to simulate the scenario in landing technique in sports . For systematically evaluation, Wright and coworkers [67, 91] conducted a computational forward dynamic simulation study to investigate the ankle biomechanics during landing on irregular surfaces. Yet there was only one quantitative investigation on the ankle biomechanics during a real ankle sprain injury scenario being reported . An accidental supination sprain injury was analyzed, where the ankle sprain injury occurred in a laboratory under a high-speed video capturing setting. It reported that the ankle joint reached an inversion of 48 degrees and an internal rotation of 10 degrees.
Diagnosis of acute ankle sprain injury
It is not uncommon for primary care physicians to misdiagnose various ankle problems as simple ankle sprains , and thus it is important to have a good differential diagnosis system for every acute ankle sprain injury (Table 1). Lynam  presented a protocol for the nurse to assess acute foot and ankle sprain at the emergency room, while Harmon  presented a systematic approach that consists of five steps to avoid missing potentially serious injuries: (1) palpation of bony structures, (2) palpation of ligamentous structures, (3) assessment of range of motion of the ankle, (4) testing of ankle muscles, and (5) special tests. Firstly, the diagnosis of fracture injuries was important as these patients normally have to be admitted to wards for emergency operative treatments . Ankle fracture injuries were commonly diagnosed with the use of radiography , or the Ottawa Ankle Rules  which had a nearly 100% sensitivity [98, 99] – it could significantly reduce the routine use of radiography [100, 101]. Secondly, palpating ligamentous structures gave an idea that which ligament is probably injured. This can also be done together with the range of motion test, especially in voluntary dorsiflexion and plantaflexion. By doing the range of motion test, the physician could at the same time examine the ankle muscles.
When fracture is ruled out, specific special tests should be performed in order to correctly diagnose if the problem is a ligamentous injury. The anterior drawer test and the talar tilt test were the two common tests to assess the integrity of the anterior talofibular ligament, and could be useful in diagnosing the grading of the tear of the ligament [39, 102]. To test the medial ligament, mainly the deltoid ligament at the medial aspect of the ankle, the eversion stress test was commonly performed . This could be tested by the external rotation test and the squeeze test . Sometimes these specific tests are performed together with radiography, that is, the stress radiography test . There were also some other devices and techniques to assist the diagnosis: magnetic resonance imaging , arthrography , sonography , three-dimensional computed tomography , bone scintography , and arthroscopic diagnosis .
Beside ligamentous injuries, the problem could be a tendon rupture. The rupture of the Achilles tendon at the rear ankle could be examined by Thompson test , where the calf of the patient was squeezed with knee flexed. If the foot moved with the plantar flexion maneuver, the Achilles tendon was at least partially intact. Peroneal tendon rupture was less sensitive to the physical examination such as subluxation test and stress radiographic assessment, and may sometimes require tendonscopy  or surgical exploration [111, 112] to confirm the diagnosis.
Grading systems for evaluating acute ankle ligamentous sprain
There were numerous grading systems to grade an acute ankle ligamentous sprain injury , as summarized in Table 2. The two most basic systems were the Anatomic System which grades the injury in three grades accordingly to the ligaments that have been damaged, and the American Medical Association Standard Nomenclature System which considers the severity of the injury to the ligaments . There were also some three-grade systems that grade the injury according to combined clinical presentation from the anatomical damage, severity of injury, and associated injuries of the surrounding structures [115–117]. Davis and Trevino  presented a staging system which consisted of four grades with some sub-grading to grade an ankle injury accordingly to the pathology, that was the damage to the ligamentous structure, and also the instability as presented clinically. Mann and coworkers  devised a practical system for outpatient clinical use. It was based on three items – pain, swelling and inability to walk. Each item was rated with 0 to 3 points (0 = none, 1 = mild, 2 = moderate, 3 = severe), and a total score was summed up for the final grading: Grade I: 1–3 points, Grade II: 4–6 points, Grade III: 7–9 points.
For dynamic functional evaluation, Kaikkonen, Kannus and Jarvinen  devised a performance test protocol with scoring scale, which consisted of three questions on subjective assessment, two clinical measurements on the ankle, two muscle strength tests, one ankle functional stability test and one balancing test, for evaluating ankle injuries. The total score correlated very well with the isokinetic strength test of the ankle, the subjective opinion about the recovery, and also the subjective function assessment, and thus the protocol was practical for clinical evaluation of ankle sprain injury. de Bie and coworkers  derived an ankle functional scoring system which evaluated the pain, instability, weight bearing, swelling and gait pattern and added up to a score of 100. Clanton  devised another system that related to the treatment protocols requested. The system consisted of two main classes which categorized the injured ankle as a stable or unstable one. The stable group was suggested to receive symptomatic treatment for pain relief. For the unstable category, another sub-category classified the patient to be non-athletes or older patients, and young active athletes. Non-athletes and older patients were suggested to receive functional treatment. For the young active athletes group, there was one more layer to divide the patients to be with negative stress radiograph findings, with positive tibio-talar stress radiograph findings, and with subtalar instability. Those with positive tibio-talar instability were suggested to consider operative surgical repair of the ligament complex.
Management of acute ankle ligamentous sprain
When an acute ankle ligamentous sprain happened, it was often the team physician to give immediate on-field care to the injured athletes . The aim was to remove the injured athlete from the field and protect the athlete from further injury, instead of to diagnose the injury immediately, as the accuracy of an on-field diagnosis was reported to be inadequate . Table 3 shows the details of some common treatments. Most commonly, the RICE (Rest, Ice-cooling, Compression, Elevation) treatment was delivered to the patients both on-field  and at the accident and emergency department [124, 125]. Cryotherapy, or ice-cooling, may help in reducing pain in the first week after the injury , however, compression and elevation could only decrease ankle swelling temporarily and the effect lasted for less than five minutes after the limb was returned to a gravity-dependent position , and may even lead to discomfort and the need for analgesia after the application of the double Tubigrip compression bandage .
In five days after the initial injury, the sensitivity of physical examination to ankle injury improved gradually after the pain and swelling had diminished . Appropriate treatments could be delivered accordingly to the diagnosis of the injured ankle. There was a general consensus to conservatively treat grade I and II ankle ligamentous injuries with functional exercises [130–132]. Trevino, Davis and Hecht  and Mattacola and Dwyer  presented some functional treatment protocols to manage ankle ligament injuries, which consisted of various modalities such as flexibility exercises, strength and balancing training, ankle joint proprioception and muscular strength training, isometric and isotonic strength training, and even exercises in water. Kerkhoffs and coworkers  conducted a systematic review and reported that functional exercises were more effective than immobilization in terms of return to sports, return to work, reduce persistent swelling, restore ankle stability, restore range of motion, and patient satisfaction.
The effect of other conservative treatments was reported by different research groups. Boyce, Quigley and Campbell  reported that the use of an Aircast ankle brace produced significant improvement in ankle joint function in 10 days and one month compared with an elastic support bandage. Madras and Barr  reported that ankle disk training on wobble board were effective in enhancing single leg balance and reducing recurrent sprain injury, while Osborne and coworkers  and Sheth and coworkers  reported the effect of ankle disk training in enhancing peroneal muscle reaction time. De Simoni and coworkers  suggested that a 12-week prescription of orthosis was effective in improving functional stability at the ankle joint. Recently, Christakou, Zervas and Lavallee  suggested that imagery may be effective in improving muscle endurance in the rehabilitation of grade II ankle sprain.
For grade III ankle sprain, the treatment was still controversial . Some surgeons recommended surgical repair , and some favored non-operative conservative treatment . In 2000, Pijnenburg and coworkers  conducted a meta-analysis and suggested that primary operative repair of lateral ankle ligaments led to better results concerning recurrent giving way and pain on activity when compared with conservative treatment. However, in 2002, the same research group  conducted another systematic review which concluded that there was still insufficient information to recommend surgery over conservative treatment, or vice versa. Lynch and Renstrom  commented that surgical treatment to ankle lateral complex may induce some serious, though infrequent complications. Functional conservative treatment was free of complications, and did not produce late symptoms than surgical repair and casting, therefore, there was a growing consensus to treat grade III sprains firstly with conservative functional treatment. If such treatment failed to enhance ankle function after a considerable period of time, surgical repair could be performed. Karlsson and Sancone  suggested that immobilization should never be used, not even in severe ankle sprain injury, as it may result in joint stiffness, muscle atrophy, and loss of proprioception.
For syndesmosis ligamentous sprains, the common treatment was to prescribe a walking boot for four to six weeks . The walking boot provided resistance to avoid the distal tibia and fibula to separate apart – a motion that imposed stress on the interosseous tibiofibular ligament between the distal tibia and fibula. The prescription lasted for four to six weeks for the interosseous tibiafibular ligament to heal.
Lastly, traditional Chinese medicine methods, such as herbs, massage and acupuncture, were well applied in China or managing sports injuries. They were treated as a kind of effective alternative method, especially in treating ankle ligamentous sprain injury. The effect was already widely reported in the Chinese literature, and also in numerous studies in the English literature, on its analgesic effect to relieve pain , reduce swelling  and edema , restoring normal ankle function [151, 152].
Sequela of ankle ligamentous sprain
Injuries to the lateral ligament of the ankle often led to ankle instability . Previous studies reported that 74% of the patients who suffered from an inversion ankle sprain injury had persisting symptoms 1.5–4 years after the injury , in which 10–30% of patients may have chronic symptoms such as persistent synovitis or tendinitis, ankle stiffness, swelling, pain, muscle weakness and frequent giving-way . Yeung and colleagues  conducted an epidemiology study and reported that for ankles sprained 1–4 times, the major residual problem was pain (24–28%), while for ankle sprained five times or more, instability problems arose and became the major sequela (38%). Chronic ankle instability was commonly divided into mechanical ankle instability and functional ankle instability [85, 155]. Mechanical ankle instability referred to abnormal laxity of the ligementous restraints, while functional ankle instability referred to normal ligamentous restraint but abnormal function with recurrent episodes of ankle giving-way . Hubbard and Hertel  suggested that mechanical ankle instability may lead to functional ankle instability, however, Birmingham and coworkers  reported that functional ankle instability could exist in the absence of mechanical ankle instability.
Chronic ankle instability could be diagnosed by various methods, including imaging , arthroscopic diagnosis , and some functional scoring system such as the Foot and Ankle Disability Index , Ankle Activity Score , and the Cumberland Ankle Instability Tool . It could lead to a delayed peroneal muscle reaction time , an inferior ankle kinesthesia and joint position sense , inferior proprioception and evertor strength . In dynamic motions, it caused significant ankle biomechanics changes in gait [165–167], in single leg drop jump , in hopping , in cutting maneuver , and in figure-of-eight running and side hopping . Beside chronic ankle instability, injuries to the lateral ligament of the ankle may also occasionally lead to ankle osteoarthritis , sinus tarsi syndrome and subtalar joint instability , and osteochondral defect at the talar dome .
Prevention of sport-related ankle sprain injury
Garrick and Requa  were the first research group to attempt to prevent ankle sprain injury. They reported that high-top shoe and prophylactic ankle taping were effective in reducing the ankle sprain injury rate among a group of 2,562 basketball players during a one year study period. In 1987, van Mechelen, Hlobil and Kemper  proposed a "sequence of injury prevention" which described how sport injury-related studies came together to form the research framework. The first step was to identify the extent of the sports injury problem by epidemiology studies. The second step established the aetiology and mechanism of injuries and the third step designed and introduced preventive measures. Finally, the effectiveness of the preventive measures was assessed by repeating the original epidemiology study (step one). From that time, numerous studies had been conducted to evaluate different strategies for ankle sprain injury prevention. The strategies could be divided into prophylactic devices, functional training, technique training, change of game rules, and education. .
For prophylactic devices, most attempts were on taping, bracing, and orthosis. The similarity of these devices was to wrap the ankle joint from the foot segment to the shank segment. Some studies suggested that these devices provided a mechanical support to resist the ankle inversion moment [178, 179], but some suggested that it instead improved the proprioception and joint position sense [180–182] and thus maintained a proper anatomical position during landing [68, 183]. The effectiveness of these devices in reducing the ankle sprain injury rate was reported in numerous studies [70, 184–186]. The role of shoe in ankle sprain prevention was less clear . Barrett and Bilisko  suggested that high-top shoe limited extreme range of motion, reduced the external stress, and enhanced proprioception of the ankle joint, while Robbins, Waked and Rappel  argued that modern athletic footwear impaired proprioception. In a combination, Rovere and coworkers  suggested a low-top shoe with a laced ankle stabilizer was effective in reducing ankle sprain injury.
Most functional training protocols consisted of stability and postural control exercises . For examples, wobble balance board or ankle disk were often used in stability training , and their effects was demonstrated in various studies [139, 191, 192]. Technique training was also prescribed by some research groups. For example, Stasinopoulos  devised a technical training program on take off and landing technique during attack and two man blocks for volleyball players which was effective in reducing ankle sprain occurrence. The aim was to coach the players to perform a quick and long final approach step and jump straight to avoid landing on the centre line under the net or on the feet of other players. Scase and coworkers  devised a program to coach a group of junior elite Australian football player with safe landing, falling, rolling, and recovery skills, to avoid the common injury mechanism which was to land badly. The program was evaluated to be successful in reducing the incidence of ankle sprain injury, especially landing-related injury.
Game rules also played significant contribute to the occurrence of injury. Andersen, Engebretsen and Bahr  reported that less than one-third of the injuries seen on video were called foul in a one-year prospective study on the Norwegian professional football league. They concluded that there may be a need for an improvement of the game rules to protect players from dangerous play. In volleyball, Reeser and coworkers  proposed a change of rule to make any centreline contact within the conflict zone between the attacker and blocker a fault, as they believed that the majority of ankle sprain injury in volleyball happened when the players collided near the net. In rugby, injuries were believed to have association with match speed and the impact forces during physical collision and tackles. Gabbett  introduced a limited interchange rule to the game, and found that the injury rate was significantly reduced in a one-year prospective study. It was suggested that the match speed and impact forces were reduced because the players got fatigued due to the limited interchange rule. Last but not the least, education to athletes was also important. In a three-day netball competition in New South Wales in Australia and 1995, Hume and Steele  reported that only 5.1% wore high-cut shoes even if this was advised before the competition. Furthermore, although players had been advised to seek immediate treatment when injured, 54.7% of players finished the game before seeking treatment. They suggested that compliance to advice from sports medicine specialists, together with the research into the effectiveness of different injury prevention strategies, were both important to the injury prevention and safety promotion in sports .
This paper summarizes the current understanding on acute ankle ligamentous sprain injury, which is the most common single type of sport-related trauma. As there is a global trend of mass participation in recreational sports, treating and preventing ankle sprain injury will become essential topics in sports medicine. Inadequate management to ankle sprain injury may lead to various sequelae and problems like functional instability and osteoarthritis. This article presents the ankle anatomy as the fundamentals, which is essential for understanding the injury and the subsequent research and improvement in treatment and prevention. Anterior talofibular ligament (ATFL) was the weakest ligament in the lateral ankle was most often getting injured in ligamentous sprain injury. Risk factors, aetiology and mechanism of ankle sprain injury were presented from a summary of previous studies. Players with a history of ankle sprain, wearing shoes with air cells in the bell and players who did not stretch before exercising were 4.9, 4.3 and 2.6 times more likely to sprain their ankle. Foot positioning and the reaction time of the lateral peroneal muscles were identified as the aetiology of ankle sprain injury. While in ankle supination sprain, there was an ankle inversion plus internal twisting of the foot, plantarlfexion with the subtalar joint adducting and inverting, and sometimes external rotation of the lower leg. A 41–45 Nm external rotatory torque would cause ankle failure. For examining the injury, diagnostic techniques and grading systems are introduced. Ankle fractures were commonly diagnosed with radiography or the Ottawa Ankle Rules. Anterior drawer test and talar tilt test were commonly used to identify ligamentous injury, while Thompson test, tendonscopy and radio graphic assessment were used to examine tendon rupture. Different grading system classify different injury level by the severity of injury to the ligaments, combined clinical presentation, the instability of ankle, and some consider multiple discipline with a scoring scale. The management, sequela and some suggestions of preventive strategies to be implemented are introduced. RICE treatment was commonly applied on-field, while Cryotherapy, ice-cooling were used in the first week after injury. Several functional treatment, braces and traditional Chinese medicine methods were usually applied after five days of injury. This review allows the reader to catch up with the previous researches on ankle sprain injury, and facilitate the future research idea on sport-related ankle sprain injury.
Fong DTP, Hong Y, Chan LK, Yung PSH, Chan KM: A systematic review on ankle injury and ankle sprain in sports. Sports Medicine. 2007, 37 (1): 73-94. 10.2165/00007256-200737010-00006.
Fong DTP, Man CY, Yung PSH, Cheung SY, Chan KM: Sport-related ankle injuries attending an accident and emergency department. Injury. 2008, 39 (10): 1222-1227. 10.1016/j.injury.2008.02.032.
Chan KM, Fong DTP, Hong Y, Yung PSH, Lui PPY: Orthopaedic sport biomechanics – a new paradigm. Clinical Biomechanics. 2008, 23 (1 Supp): 21-30. 10.1016/j.clinbiomech.2007.10.007.
Burnham JM: Exercise is medicine: health benefits of regular physical activity. The Journal of the Louisiana State Medical Society. 1998, 150 (7): 319-323.
Hong Kong Sports Development Board: Sports Participation Survey 2001. Hong Kong. 2003
Hui SC, Morrow JR: Level of participation and knowledge of physical activity in Hong Kong Chinese adults and their association with age. Journal of Aging and Physical Activity. 2001, 9 (4): 372-385.
Hui SSC, Thomas N, Tomlinson B: Relationship between physical activity, fitness, and CHD risk factors in middle-age Chinese. Journal of Physical Activity and Health. 2005, 2 (3): 307-323.
Hong Kong Amateur Athletic Association: Event history of Standard Chartered Hong Kong Marathon. Hong Kong. 2008
Chan KM, Yuan Y, Li CK, Chien P, Tsang G: Sports causing most injuries in Hong Kong. British Journal of Sports Medicine. 1993, 27 (4): 263-267. 10.1136/bjsm.27.4.263.
de Loes M, Goldie I: Incidence rate of injuries during sport activity and physical exercise in a rural Swedish municipality: incidence rates in 17 sports. International Journal of Sports Medicine. 1988, 9 (6): 461-467. 10.1055/s-2007-1025052.
Jones RS, Taggart T: Sport related injuries attending the accident and emergency department. British Journal of Sports Medicine. 1994, 28 (2): 110-111. 10.1136/bjsm.28.2.110.
Abernethy L, MacAuley D: Impact of school sports injury. British Journal of Sports Medicine. 2003, 37 (4): 354-355. 10.1136/bjsm.37.4.354.
Shephard RJ: Can we afford to exercise, given current injury rates?. Injury Prevention. 2003, 9 (2): 99-100. 10.1136/ip.9.2.99.
Fahlstrom M, Yeap JS, Alfredson H, Soderman K: Shoulder pain – a common problem in world-class badminton players. Scandinavian Journal of Medicine and Science in Sports. 2006, 16 (3): 168-173. 10.1111/j.1600-0838.2004.00427.x.
Orchard J, Hoskins W: For debate: consensus injury definitions in team sports should focus on missed playing time. Clinical Journal of Sport Medicine. 2007, 17 (3): 192-196. 10.1097/JSM.0b013e3180547527.
Knowles SB, Marshall SW, Miller T, Spicer R, Bowling JM, Loomis D, Millikan RW, Yang J, Mueller FO: Cost of injuries from a prospective cohort study of North Carolina high school athletes. Injury Prevention. 2007, 13 (6): 416-421. 10.1136/ip.2006.014720.
Jensen SL, Andresen BK, Mencke S, Nielsen PT: Epidemiology of ankle fractures. A prospective population-based study of 212 cases in Aalborg, Denmark. Acta Orthopaedica Scandinavica. 1998, 69 (1): 48-50.
Hertel J: Functional instability following lateral ankle sprain. Sports Medicine. 2000, 29 (5): 361-371. 10.2165/00007256-200029050-00005.
Willems TM, Witvrouw E, Verstuyft J, Vaes P, De Clercq D: Proprioception and muscle strength in subjects with a history of ankle sprains and chronic instability. Journal of Athletic Training. 2002, 37 (4): 487-493.
Fu AS, Hui-Chan CW: Ankle joint proprioception and postural control in basketball players with bilateral ankle sprains. American Journal of Sports Medicine. 2005, 33 (8): 1174-1182. 10.1177/0363546504271976.
Airaksinen O: Changes in posttraumatic ankle joint mobility, pain, and edema following intermittent pneumatic compression therapy. Archives in Physical Medicine and Rehabilitation. 1989, 70 (4): 341-344.
Gerber JP, Williams GN, Scoville CR, Arciero RA, Taylor DC: Persistent disability associated with ankle sprains: a prospective examination of an athletic population. Foot and Ankle International. 1998, 19 (10): 653-660.
Drawer S, Fuller CW: Perceptions of retired professional soccer players about the provision of support services before and after retirement. British Journal of Sports Medicine. 2002, 36 (1): 33-38. 10.1136/bjsm.36.1.33.
Lohmander LS, Englund PM, Dahl LL, Roos EM: The long-term consequence of anterior cruciate ligament and meniscus injuries: osteoarthritis. American Journal of Sports Medicine. 2007, 35 (10): 1756-1769. 10.1177/0363546507307396.
Marchi AG, Di Bello D, Messi G, Gazzola G: Permanent sequelae in sports injuries: a population based study. Archives of Disease in Childhood. 1999, 81 (4): 324-328. 10.1136/adc.81.4.324.
Adirim TA, Cheng TL: Overview of injuries in the young athlete. Sports Medicine. 2003, 33 (1): 75-81. 10.2165/00007256-200333010-00006.
Hootman JM, Dick R, Agel J: Epidemiology of collegiate injuries for 15 sports: summary and recommendations for injury prevention initiatives. Journal of Athletic Training. 2007, 42 (2): 311-319.
Purves S, Chan KM: Injury profile of runners in the 1987 Hong Kong International Marathon. The Journal of The Hong Kong Physiotherapy Association. 1987, 9: 24-28.
Garrick JG, Requa RK: The epidemiology of foot and ankle injuries in sports. Clinics in Sports Medicine. 1988, 7 (1): 29-36.
Ferran NA, Maffulli N: Epidemiology of sprains of the lateral ankle ligament complex. Foot and Ankle Clinics. 2006, 11 (3): 659-662. 10.1016/j.fcl.2006.07.002.
MacAuley D: Ankle injuries: same joint, different sports. Medicine and Science in Sports and Exercise. 1999, 31 (7 Supp): 409-411.
Woods C, Hawkins R, Hulse M, Hodson A: The Football Association Medical Research Programme: an audit of injuries in professional football: an analysis of ankle sprains. British Journal of Sports Medicine. 2003, 37 (3): 233-238. 10.1136/bjsm.37.3.233.
Renstrom PA, Konradsen L: Ankle ligament injuries. British Journal of Sports Medicine. 1997, 31 (1): 11-20. 10.1136/bjsm.31.1.11.
Yeung MS, Chan KM, So CH, Yuan WY: An epidemiological survey on ankle sprain. British Journal of Sports Medicine. 1994, 28 (2): 112-116. 10.1136/bjsm.28.2.112.
Attarian DE, McCrackin HJ, DeVito DP, McElhaney JE, Garrett WE: Biomechanical characteristics of human ankle ligaments. Foot and Ankle. 1985, 6 (2): 54-58.
Harmon KG: The ankle examination. Primary Care; Clinics in Office Practice. 2004, 31 (4): 1025-1037. 10.1016/j.pop.2004.07.008.
Bozkurt M, Doral MN: Anatomic factors and biomechanics in ankle instability. Foot and Ankle Clinics. 2006, 11 (3): 451-463. 10.1016/j.fcl.2006.06.001.
Attarian DE, McCrackin HJ, DeVito DP, McElhaney JE, Garrett WE: A biomechanical study of human ankle ligaments and autogenous reconstructive grafts. American Journal of Sports Medicine. 1985, 13 (6): 377-381. 10.1177/036354658501300602.
Bennett WF: Lateral ankle sprains. Part I: Anatomy, biomechanics, diagnosis, and natural history. Orthopaedic Review. 1994, 23 (5): 381-387.
Burks RT, Morgan J: Anatomy of the lateral ankle ligaments. American Journal of Sports Medicine. 1994, 22 (1): 72-77. 10.1177/036354659402200113.
Stephens MM, Sammarco GJ: The stabilizing role of the lateral ligament complex around the ankle and subtalar joints. Foot and Ankle. 1992, 13 (3): 130-136.
Nigg BM, Skarvan G, Frank CB, Yeadon MR: Elongation and forces of ankle ligaments in a physiological range of motion. Foot and Ankle. 1990, 11 (1): 30-40.
Bahr R, Pena F, Shine J, Lew WD, Engebretsen L: Ligament force and joint motion in the intact ankle: a cadaveric study. Knee Surgery Sports Traumatology Arthroscopy. 1998, 6 (2): 115-121. 10.1007/s001670050083.
Viladot A, Lorenzo JC, Salazar J, Rodriquez A: The subtalar joint: embryology and morphology. Foot and Ankle. 1984, 5 (2): 54-66.
Rockar PA: The subtalar joint: anatomy and joint motion. Journal of Orthopaedic and Sports Physical Therapy. 1995, 21 (6): 361-372.
Perry J: Anatomy and biomechanics of the hindfoot. Clinical Orthopaedics and Related Research. 1983, 9-15. 177
Inman V: The joints of the ankle. 1976, Baltimore, MD: Williams & Wilkins
Harper MC: The lateral ligamentous support of the subtalar joint. Foot and Ankle. 1991, 11 (6): 354-358.
Pena FA, Coetzee JC: Ankle syndesmosis injuries. Foot and Ankle Clinics. 2006, 11 (1): 35-50. 10.1016/j.fcl.2005.12.007.
Karrholm J, Hansson LI, Selvik G: Mobility of the lateral malleolus. A roentgen stereophotogrammetric analysis. Acta Orthopaedica Scandinavica. 1985, 56 (6): 479-483.
Williams GN, Jones MH, Amendola A: Syndesmotic ankle sprains in athletes. American Journal of Sports Medicine. 2007, 35 (7): 1197-1207. 10.1177/0363546507302545.
Jones MH, Amendola A: Syndesmosis sprains of the ankle: A systematic review. Clinical Orthopaedics and Related Research. 2007, 173-175. 10.1097/BLO.0b013e31802eb471. 455
Lysens R, Steverlynck A, Auweele van den Y, Lefevre J, Renson L, Claessens A, Ostyn M: The predictability of sports injuries. Sports Medicine. 1984, 1 (1): 6-10. 10.2165/00007256-198401010-00002.
Barker HB, Beynnon BD, Renstrom PA: Ankle injury risk factors in sports. Sports Medicine. 1997, 23 (2): 69-74. 10.2165/00007256-199723020-00001.
Beynnon BD, Murphy DF, Alosa DM: Predictive factors for lateral ankle sprains: a literature review. Journal of Athletic Training. 2002, 37 (4): 376-380.
Morrison KE, Kaminski TW: Foot characteristics in association with inversion ankle injury. Journal of Athletic Training. 2007, 42 (1): 135-142.
McKay GD, Goldie PA, Payne WR, Oakes BW: Ankle injuries in basketball: injury rate and risk factors. British Journal of Sports Medicine. 2001, 35 (2): 103-108. 10.1136/bjsm.35.2.103.
Trojian TH, McKeag DB: Single leg balance test to identify risk of ankle sprains. British Journal of Sports Medicine. 2006, 40 (7): 610-613. 10.1136/bjsm.2005.024356.
Tyler TF, McHugh MP, Mirabella MR, Mullaney MJ, Micholas SJ: Risk factors for noncontact ankle sprains in high school football players: the role of previous ankle sprains and body mass index. American Journal of Sports Medicine. 2006, 34 (3): 471-475.
de Noronha M, Refshauge K, Herbert R, Kilbreath SL: Do voluntary strength, proprioception, range of motion, or postural sway predict occurrence of lateral ankle sprain?. British Journal of Sports Medicine. 2006, 40 (10): 824-828. 10.1136/bjsm.2006.029645.
Orchard JW, Powell JW: Risk of knee and ankle sprains under various weather conditions in American football. Medicine and Science in Sports and Exercise. 2003, 35 (7): 1118-1123. 10.1249/01.MSS.0000074563.61975.9B.
Eren OT, Kucukkaya M, Kabukcuoglu Y, Kuzgun U: The role of a posteriorly positioned fibula in ankle sprain. American Journal of Sports Medicine. 2003, 31 (6): 995-998.
Willems TM, Witvrouw E, Delbaere K, De Cock A, De Clercq D: Relationship between gait biomechanics and inversion sprains: a prospective study of risk factors. Gait and Posture. 2005, 21 (4): 379-387. 10.1016/j.gaitpost.2004.04.002.
Willems TM, Witvrouw E, Delbaere K, Mahieu N, De Bourdeaudhuij I, De Clercq D: Intrinsic risk factors for inversion ankle sprains in male subjects: a prospective study. American Journal of Sports Medicine. 2005, 33 (3): 415-423. 10.1177/0363546504268137.
Willems TM, Witvrouw E, Delbaere K, Philippaerts R, De Bourdeaudhuij I, De Clercq D: Intrinsic risk factors for inversion ankle sprains in female – a prospective study. Scandinavian Journal of Medicine and Science in Sports. 2005, 15 (5): 336-345. 10.1111/j.1600-0838.2004.00428.x.
Fuller EA: Center of pressure and its theoretical relationship to foot pathology. Journal of the American Podiatric Medical Association. 1999, 89 (6): 278-291.
Wright IC, Neptune RR, Bogert van den AJ, Nigg BM: The influence of foot positioning on ankle sprains. Journal of Biomechanics. 2000, 33 (5): 513-519. 10.1016/S0021-9290(99)00218-3.
Eils E, Rosenbaum D: The main function of ankle braces is to control the joint position before landing. Foot and Ankle International. 2003, 24 (3): 263-268.
Ashton-Miller JA, Ottaviani RA, Hutchinson C, Wojtys EM: What best protects the inverted weightbearing ankle against further inversion? Evertor muscle strength compares favorably with shoe height, athletic tape, and three orthoses. American Journal of Sports Medicine. 1996, 24 (6): 800-809. 10.1177/036354659602400616.
Surve I, Schwellnus MP, Noakes T, Lombard C: A fivefold reduction in the incidence of recurrent ankle sprains in soccer players using the Sport-Stirrup orthosis. American Journal of Sports Medicine. 1994, 22 (5): 601-606. 10.1177/036354659402200506.
Dufek JS, Bates BT: Biomechanical factors associated with injury during landing in jump sports. Sports Medicine. 1991, 12 (5): 326-337. 10.2165/00007256-199112050-00005.
Hopper D, Allison G, Fernandes N, O'Sullivan L, Wharton A: Reliability of the peroneal latency in normal ankles. Clinical Orthopaedics and Related Research. 1998, 159-165. 350
Vaes P, Duquet W, Van Gheluwe B: Peroneal reaction times and eversion motor response in healthy and unstable ankles. Journal of Athletic Training. 2002, 37 (4): 475-480.
Ty Hopkins J, McLoda T, McCaw S: Muscle activation following sudden ankle inversion during standing and walking. European Journal of Applied Physiology. 2007, 99 (4): 371-378. 10.1007/s00421-006-0356-9.
Konradsen L, Olesen S, Hansen HM: Ankle sensorimotor control and eversion strength after acute ankle inversion injuries. American Journal of Sports Medicine. 1998, 26 (1): 72-77.
Konradsen L, Ravn JB: Prolonged peroneal reaction time in ankle instability. International Journal of Sports Medicine. 1991, 12 (3): 290-292. 10.1055/s-2007-1024683.
Isakov E, Mizrahi J, Solzi P, Susak Z, Lotem M: Response of the peroneal muscles to sudden inversion of the ankle during standing. International Journal of Sport Biomechanics. 1986, 2 (2): 100-109.
Karlsson J, Andreasson GO: The effect of external ankle support in chronic lateral ankle joint instability. An electromyographic study. American Journal of Sports Medicine. 1992, 20 (3): 257-261. 10.1177/036354659202000304.
Konradsen L, Peura G, Beynnon B, Renstrom P: Ankle eversion torque response to sudden ankle inversion torque response in unbraced, braced, and pre-activated situations. Journal of Orthopaedic Research. 2005, 23 (2): 315-321. 10.1016/j.orthres.2004.07.005.
Konradsen L, Voigt M, Hojsgaard C: Ankle inversion injuries. The role of the dynamic defense mechanism. American Journal of Sports Medicine. 1997, 25 (1): 54-58. 10.1177/036354659702500110.
Bahr R, Krosshaug T: Understanding injury mechanisms: a key component of preventing injuries in sport. British Journal of Sports Medicine. 2005, 39 (6): 324-329. 10.1136/bjsm.2005.018341.
Krosshaug T, Andersen TE, Olsen OE, Myklebust G, Bahr R: Research approaches to describe the mechanisms of injuries in sport: limitations and possibilities. British Journal of Sports Medicine. 2005, 39 (6): 330-339. 10.1136/bjsm.2005.018358.
Safran MR, Benedetti RS, Bartolozzi AR, Mandelbaum BR: Lateral ankle sprains: a comprehensive review: part 1: etiology, pathoanatomy, histopathogenesis, and diagnosis. Medicine and Science in Sports and Exercise. 1999, 31 (7 Supp): 429-437.
Vitale TD, Fallat LM: Lateral ankle sprains: evaluation and treatment. Journal of Foot Surgery. 1988, 27 (3): 248-258.
Hertel J: Functional anatomy, pathomechanics, and pathophysiology of lateral ankle instability. Journal of Athletic Training. 2002, 37 (4): 364-375.
Stormont DM, Morrey BF, An KN, Cass JR: Stability of the loaded ankle. Relation between articular restraint and primary and secondary static restraints. American Journal of Sports Medicine. 1985, 13 (5): 295-300. 10.1177/036354658501300502.
Andersen TE, Floerenes TW, Arnason A, Bahr R: Video analysis of the mechanisms for ankle injuries in football. American Journal of Sports Medicine. 2004, 32 (1 Supp): 69-79.
Self BP, Harris S, Greenwald RM: Ankle biomechanics during impact landings on uneven surfaces. Foot and Ankle International. 2000, 21 (2): 138-144.
Markolf KL, Schmalzried TP, Ferkel RD: Torsional strength of the ankle in vitro. The supination-external-rotation injury. Clinical Orthopaedics and Related Research. 1989, 266-272. 246
Self BP, Paine D: Ankle biomechanics during four landing techniques. Medicine and Science in Sports and Exercise. 2001, 33 (8): 1338-1344. 10.1097/00005768-200108000-00015.
Wright IC, Neptune RR, Bogert van den AJ, Nigg BM: The effects of ankle compliance and flexibility on ankle sprains. Medicine and Science in Sports and Exercise. 2000, 32 (2): 260-265. 10.1097/00005768-200002000-00002.
Fong DTP, Hong Y, Shima Y, Krosshaug T, Yung PSH, Chan KM: Biomechanics of supination ankle sprain – a case report of an accidental injury event in laboratory. American Journal of Sports Medicine. 2009, 37 (4): 822-827. 10.1177/0363546508328102.
LeBlanc KE: Ankle problems masquerading as sprains. Primary Care; Clinics in Office Practice. 2004, 31 (4): 1055-1067. 10.1016/j.pop.2004.07.010.
Lynam L: Assessment of acute foot and ankle sprains. Emergency Nurse. 2006, 14 (4): 24-33.
Mak KH, Chan KM, Leung PC: Ankle fracture treated with the AO principle – an experience with 116 cases. Injury. 1985, 16 (4): 265-272. 10.1016/S0020-1383(85)80017-6.
Uys HD, Rijke AM: Clinical association of acute lateral ankle sprain with syndesmotic involvement: a stress radiography and magnetic resonance imaging study. American Journal of Sports Medicine. 2002, 30 (6): 816-822.
Stiell I: Ottawa ankle rules. Canadian Family Physician. 1996, 42: 478-480.
DiGiovanni BF, Partal G, Baumhauer JF: Acute ankle injury and chronic lateral instability in the athlete. Clinics in Sports Medicine. 2004, 23 (1): 1-19. 10.1016/S0278-5919(03)00095-4.
Childs S: Acute ankle injury. Lippincott's Primary Care Practice. 1999, 3 (4): 428-437.
Papacostas E, Malliaropoulos N, Papadopoulos A, Liouliakis C: Validation of Ottawa ankle rules protocol in Greek athletes: study in the emergency departments of a district general hospital and a sports injuries clinic. British Journal of Sports Medicine. 2001, 35 (6): 445-447. 10.1136/bjsm.35.6.445.
Leddy JJ, Smolinski RJ, Lawrence J, Snyder JL, Priore RL: Prospective evaluation of the Ottawa Ankle Rules in a university sports medicine center. With a modification to increase specificity for identifying malleolar fractures. American Journal of Sports Medicine. 1998, 26 (2): 158-165.
Bahr R, Pena F, Shine J, Lew WD, Lindquist C, Tyrdal S, Engebretsen L: Mechanics of the anterior drawer and talar tilt tests. A cadaveric study of lateral ligament injuries of the ankle. Acta Orthopaedica Scandinavica. 1997, 68 (5): 435-441.
Hintermann B, Knupp M, Pagenstert GI: Deltoid ligament injuries: diagnosis and management. Foot and Ankle Clinics. 2006, 11 (3): 625-637. 10.1016/j.fcl.2006.08.001.
Campbell SE: MRI of sports injuries of the ankle. Clinics in Sports Medicine. 2006, 25 (4): 727-762. 10.1016/j.csm.2006.06.009.
van Dijk CN, Molenaar AH, Cohen RH, Tol JL, Bossuyt PM, Marti RK: Value of arthrography after supination trauma of the ankle. Skeletal Radiology. 1998, 27 (5): 256-261. 10.1007/s002560050377.
Milz P, Milz S, Steinborn M, Mittlmeier T, Putz R, Reiser M: Lateral ankle ligaments and tibiofibular syndesmosis. 13-MHz high-frequency sonography and MRI compared in 20 patients. Acta Orthopaedica Scandinavica. 1998, 69 (1): 51-55.
Nakasa T, Fukuhara K, Adachi N, Ochi M: Evaluation of anterior talofibular ligament lesion using 3-dimensional computed tomography. Journal of Computer Assisted Tomography. 2006, 30 (3): 543-547. 10.1097/00004728-200605000-00032.
Philbin TM, Lee TH, Berlet GC: Arthroscopy for athletic foot and ankle injuries. Clinics in Sports Medicine. 2004, 23 (1): 35-53. 10.1016/S0278-5919(03)00093-0.
Morelli V, James E: Achilles tendonopathy and tendon rupture: conservative versus surgical management. Primary Care; Clinics in Office Practice. 2004, 31 (4): 1039-1054. 10.1016/j.pop.2004.07.009.
Scholten PE, van Dijk CN: Tendoscopy of the peroneal tendons. Foot and Ankle Clinics. 2006, 11 (2): 415-420. 10.1016/j.fcl.2006.03.004.
Minoyama O, Uchiyama E, Iwaso H, Hiranuma K, Takeda Y: Two cases of peroneus brevis tendon tear. British Journal of Sports Medicine. 2002, 36 (1): 65-66. 10.1136/bjsm.36.1.65.
Verheyen CP, Bras J, van Dijk CN: Rupture of both peroneal tendons in a professional athlete. A case report. American Journal of Sports Medicine. 2000, 28 (6): 897-900.
Mann G, Nysha M, Constantini N, Matan Y, Renstrom P, Lynch SA: Mechanics of injury, clinical presentation, and staging. The Uns table Ankle. Edited by: Nyska M, Mann G. 2002, Human Kinetics, 54-60.
Clanton TO: Athletic injuries to the soft tissues of the foot and ankle. Surgery of the Foot and Ankle. Edited by: Coughlin MJ, Mann RA. 1999, St Louis: Mosby, 1090-1209.
Jackson DW, Ashley RL, Powell JW: Ankle sprains in young athletes. Relation of severity and disability. Clinical Orthopaedics and Related Research. 1974, 201-215. 101
Hamilton WG: Sprained ankles in ballet dancers. Foot and Ankle. 1982, 3 (2): 99-102.
Crichton KJ, Fricker PA, Purdam CR, Watson AS: Injuries to the pelvis and lower limb. Textbook of science and medicine in sport. Edited by: Bloomfield J, Fricker PA, Fitch KD. 1992, Massachusetts: Blackwell Scientific Publications, 381-420.
Davis PF, Trevino S: Ankle injuries. The Foot and Ankle in Sport. Edited by: Baxter D. 1995, Mosby, 147-169.
Kaikkonen A, Kannus P, Jarvinen M: A performance test protocol and scoring scale for the evaluation of ankle injuries. American Journal of Sports Medicine. 1994, 22 (4): 462-469. 10.1177/036354659402200405.
de Bie RA, de Vet HC, Wildenberg van den FA, Lenssen FA, Knipschild PG: The prognosis of ankle sprains. International Journal of Sports Medicine. 1997, 18 (4): 285-289. 10.1055/s-2007-972635.
Stanish WD, Evans NA: The modern-day team physician: roles, responsibilities, and required qualifications. F.I.M.S. Team Physician Manual. Edited by: Chan KM, Micheli L, Smith A, Rolf C, Bachl N, Frontera W, Alenabi T. 2006, Hong Kong: CD Concept, 3-11. 2
van Dijk CN, Mol BW, Lim LS, Marti RK, Bossuyt PMM: Diagnosis of ligament rupture of the ankle joint. Physical examination, arthrography, stress radiography and sonography compared in 160 patients after inversion trauma. Acta Orthopaedica Scandinavica. 1996, 67 (6): 566-570.
Wolfe MW, Uhl TL, Mattacola CG, McCluskey LC: Management of ankle sprains. American Family Physician. 2001, 63 (1): 93-104.
Johannsen F, Langberg H: The treatment of acute soft tissue trauma in Danish emergency rooms. Scandinavian Journal of Medicine and Science in Sports. 1997, 7 (3): 178-181.
Cooke MW, Lamb SE, Marsh J, Dale J: A survey of current consultant practice of treatment of severe ankle sprains in emergency departments in the United Kingdom. Emergency Medicine Journal. 2003, 20 (6): 505-507. 10.1136/emj.20.6.505.
Bleakley CM, McDonough SM, MacAuley DC, Bjordal J: Cryotherapy for acute ankle sprains: a randomised controlled study of two different icing protocols. British Journal of Sports Medicine. 2006, 40 (8): 700-705. 10.1136/bjsm.2006.025932.
Tsang KK, Hertel J, Denegar CR: Volume decreases after elevation and intermittent compression of postacute ankle sprains are negated by gravity-dependent positioning. Journal of Athletic Training. 2003, 38 (4): 320-324.
Watts BL, Armstrong B: A randomised controlled trial to determine the effectiveness of double Tubigrip in grade 1 and 2 (mild to moderate) ankle sprains. Emergency Medicine Journal. 2001, 18 (1): 46-50. 10.1136/emj.18.1.46.
van Dijk CN, Lim LS, Bossuyt PM, Marti RK: Physical examination is sufficient for the diagnosis of sprained ankles. Journal of Bone and Joint Surgery – British Volume. 1996, 78 (6): 958-962. 10.1302/0301-620X78B6.1283.
Lynch SA, Renstrom PA: Treatment of acute lateral ankle ligament rupture in the athlete. Conservative versus surgical treatment. Sports Medicine. 1999, 27 (1): 61-71. 10.2165/00007256-199927010-00005.
Safran MR, Zachazewski JE, Benedetti RS, Bartolozzi AR, Mandelbaum R: Lateral ankle sprains: a comprehensive review: part 2: treatment and rehabilitation with an emphasis on the athlete. Medicine and Science in Sports and Exercise. 1999, 31 (7 Supp): 438-447.
Osborne MD, Rizzo TD: Prevention and treatment of ankle sprain in athletes. Sports Medicine. 2003, 33 (15): 1145-1150. 10.2165/00007256-200333150-00005.
Trevino SG, Davis P, Hecht PJ: Management of acute and chronic lateral ligament injuries of the ankle. Orthopedic Clinics of North America. 1994, 25 (1): 1-16.
Mattacola CG, Dwyer MK: Rehabilitation of the ankle after acute sprain or chronic instability. Journal of Athletic Training. 2002, 37 (4): 413-429.
Kerkhoffs GM, Rowe BH, Assendelft WJ, Kelly KD, Struijs PA, van Dijk CN: Immobilisation for acute ankle sprain. A systematic review. Archives of Orthopaedic and Trauma Surgery. 2001, 121 (8): 462-471. 10.1007/s004020100283.
Boyce SH, Quigley MA, Campbell S: Management of ankle sprains: a randomised controlled trial of the treatment of inversion injuries using an elastic support bandage or an Aircast ankle brace. British Journal of Sports Medicine. 2005, 39 (2): 91-96. 10.1136/bjsm.2003.009233.
Madras D, Barr JB: Rehabilitation for functional ankle instability. Journal of Sport Rehabilitation. 2003, 12 (2): 133-142.
Osborne MD, Chou LS, Laskowski ER, Smith J, Kaufman KR: The effect of ankle disk training on muscle reaction time in subjects with a history of ankle sprain. American Journal of Sports Medicine. 2001, 29 (5): 627-632.
Sheth P, Yu B, Laskowski ER, An KN: Ankle disk training influences reaction times of selected muscles in a simulated ankle sprain. American Journal of Sports Medicine. 1997, 25 (4): 538-543. 10.1177/036354659702500418.
De Simoni C, Wetz HH, Zanetti M, Hodler J, Jacob J, Zollinger H: Clinical examination and magnetic resonance imaging in the assessment of ankle sprains treated with an orthosis. Foot and Ankle International. 1996, 17 (3): 177-182.
Christakou A, Zervas Y, Lavallee D: The adjunctive role of imagery on the functional rehabilitation of a grade II ankle sprain. Human Movement Science. 2007, 26 (1): 141-154. 10.1016/j.humov.2006.07.010.
Brand RL, Collins MD, Templeton T: Surgical repair of ruptured alteral ankle ligaments. American Journal of Sports Medicine. 1981, 9 (1): 40-44. 10.1177/036354658100900109.
Drez D, Young JC, Waldman D, Shackleton R, Parker W: Nonoperative treatment of double lateral ligament tears of the ankle. American Journal of Sports Medicine. 1982, 10 (4): 197-200. 10.1177/036354658201000401.
Pijnenburg AC, van Dijk CN, Bossuyt PM, Marti RK: Treatment of ruptures of the lateral ankle ligaments: a meta-analysis. Journal of Bone and Joint Surgery – American Volume. 2000, 82 (6): 761-773.
Kerkhoffs GM, Rowe BH, Assendelft WJ, Kelly K, Struijs PA, van Dijk CN: Immobilisation and functional treatment for acute lateral ankle ligament injuries in adults. Cochrane Database of Systematic Reviews. 2002, CD003762-3
Karlsson J, Sancone M: Management of acute ligament injuries of the ankle. Foot and Ankle Clinics. 2006, 11 (3): 521-530. 10.1016/j.fcl.2006.07.008.
Silvestri PG, Uhl TL, Madaleno JA, Johnson DL, Blackport RM: Management of syndesmotic ankle sprains. Athletic Therapy Today. 2002, 7 (5): 48-49.
Koo ST, Park YI, Lim KS, Chung K, Chung JM: Acupuncture analgesia in a new rat model of ankle sprain pain. Pain. 2002, 99 (3): 423-431. 10.1016/S0304-3959(02)00164-1.
Mou ZX: Treatment of 31 cases of acute ankle sprain by puncturing yangchi. Journal of Traditional Chinese Medicine. 1987, 7 (1): 71.
Hahm TS: The effect of 2 Hz and 100 Hz electrical stimulation of acupoint on ankle sprain in rats. Journal of Korean Medical Science. 2007, 22 (2): 347-351. 10.3346/jkms.2007.22.2.347.
Wu L, Jin Y: Application of finger pressure to ankle sprains. Journal of Traditional Chinese Medicin. 1993, 13 (4): 299-302.
Zhang F, Miao Y: ncture treatment for sprains of the ankle joint in 354 cases. Journal of Traditional Chinese Medicine. 1990, 10 (3): 207-208.
Freeman MA: Instability of the foot after injuries to the lateral ligament of the ankle. Journal of Bone and Joint Surgery – British Volume. 1965, 47 (4): 669-677.
Anandacoomarasamy A, Barnsley L: Long term outcomes of inversion ankle injuries. British Journal of Sports Medicine. 2005, 39 (3): e14-10.1136/bjsm.2004.011676.
Krips R, de Vries J, van Dijk CN: Ankle instability. Foot and Ankle Clinics. 2006, 11 (2): 311-329. 10.1016/j.fcl.2006.02.003.
Hubbard TJ, Hertel J: Mechanical contributions to chronic lateral ankle instability. Sports Medicine. 2006, 36 (3): 263-277. 10.2165/00007256-200636030-00006.
Birmingham TB, Chesworth BM, Hartsell HD, Stevenson AL, Lapenskie GL, Vandervoort AA: Peak passive resistive torque at maximum inversion range of motion in subjects with recurrent ankle inversion sprains. Journal of Orthopaedic and Sports Physical Therapy. 1997, 25 (5): 342-348.
Griffith JF, Brockwell J: Diagnosis and imaging of ankle instability. Foot and Ankle Clinics. 2006, 11 (3): 475-496. 10.1016/j.fcl.2006.07.001.
Hintermann B, Boss A, Schafer D: Arthroscopic findings in patients with chronic ankle instability. American Journal of Sports Medicine. 2002, 30 (3): 402-409.
Hale SA, Hertel J: Reliability and sensitivity of the foot and ankle disability index in subjects with chronic ankle instability. Journal of Athletic Training. 2005, 40 (1): 35.
Halasi T, Kynsburg A, Tallay A, Berkes I: Development of a new activity score for the evaluation of ankle instability. American Journal of Sports Medicine. 2004, 32 (4): 899-908. 10.1177/0363546503262181.
Hiller CE, Refshauge KM, Bundy AC, Herbert RS, Kilbreath SL: The Cumberland ankle instability tool: a report of validity and reliability testing. Archives of Physical Medicine and Rehabilitation. 2006, 87 (9): 1235-1241. 10.1016/j.apmr.2006.05.022.
Lofvenberg R, Karrholm J, Sundelin G, Ahlgren O: Prolonged reaction time in patients with chronic lateral instability of the ankle. American Journal of Sports Medicine. 1995, 23 (4): 414-417. 10.1177/036354659502300407.
Konradsen L: Factors contributing to chronic ankle instability: kinesthesia and joint position sense. Journal of Athletic Training. 2002, 37 (4): 381-385.
Monaghan K, Delahunt E, Caulfield B: Ankle function during gait in patients with chronic ankle instability compared to controls. Clinical Biomechanics. 2006, 21 (2): 168-174. 10.1016/j.clinbiomech.2005.09.004.
Nyska M, Shabat S, Simkin A, Neeb M, Matan Y, Mann G: Dynamic force distribution during level walking under the feet of patients with chronic ankle instability. British Journal of Sports Medicine. 2003, 37 (6): 495-497. 10.1136/bjsm.37.6.495.
Delahunt E, Monaghan K, Caulfield B: Altered neuromuscular control and ankle joint kinematics during walking in subjects with functional instability of the ankle joint. American Journal of Sports Medicine. 2006, 34 (12): 1970-1976. 10.1177/0363546506290989.
Delahunt E, Monaghan K, Caulfield B: Changes in lower limb kinematics, kinetics, and muscle activity in subjects with functional instability of the ankle joint during a single leg drop jump. Journal of Orthopaedic Research. 2006, 24 (10): 1991-2000. 10.1002/jor.20235.
Delahunt E, Monaghan K, Caulfield B: Ankle function during hopping in subjects with functional instability of the ankle joint. Scandinavian Journal of Medicine and Science in Sports. 2007, 17 (6): 641-648.
Dayakidis MK, Boudolos K: Ground reaction force data in functional ankle instability during two cutting movements. Clinical Biomechanics. 2006, 21 (4): 405-411. 10.1016/j.clinbiomech.2005.11.010.
Ross SE, Guskiewicz KM, Gross MT, Yu B: Assessment tools for identifying functional limitations associated with functional ankle instability. Journal of Athletic Training. 2008, 43 (1): 44-50.
Valderrabano V, Hintermann B, Horisberger M, Fung TS: Ligamentous posttraumatic ankle osteoarthritis. American Journal of Sports Medicine. 2006, 34 (4): 612-620. 10.1177/0363546505281813.
Pisani G, Pisani PC, Parino E: Sinus tarsi syndrome and subtalar joint instability. Clinics in Podiatric Medicine and Surgery. 2005, 22 (1): 63-77. 10.1016/j.cpm.2004.08.005.
Tol JL, Struijs PA, Bossuyt PM, Verhagen RA, van Dijk CN: Treatment strategies in osteochondral defects of the talar dome: a systematic review. Foot and Ankle International. 2000, 21 (2): 119-126.
Garrick JG, Requa RK: Role of external support in the prevention of ankle sprains. Medicine and Science in Sports. 1973, 5 (3): 200-203.
van Mechelen W, Hlobil H, Kemper HCG: Incidence, severity, aetiology and prevention of sports injuries: a review of concepts. Sports Medicine. 1992, 14 (2): 82-99. 10.2165/00007256-199214020-00002.
Abernethy L, Bleakley C: Strategies to prevent injury in adolescent sport: a systematic review. British Journal of Sports Medicine. 2007, 41 (10): 627-638. 10.1136/bjsm.2007.035691.
Ubell ML, Boylan JP, Ashton-Miller JA, Wojtys EM: The effect of ankle braces on the prevention of dynamic forced ankle inversion. American Journal of Sports Medicine. 2003, 31 (6): 935-940.
Ottaviani RA, Ashton-Miller JA, Kothari SU, Wojtys EM: Basketball shoe height and the maximal muscular resistance to applied ankle inversion and eversion moments. American Journal of Sports Medicine. 1995, 23 (4): 418-423. 10.1177/036354659502300408.
Firer P: Effectiveness of taping for the prevention of ankle ligament sprains. British Journal of Sports Medicine. 1990, 24 (1): 47-50. 10.1136/bjsm.24.1.47.
Hume PA, Gerrard DF: Effectiveness of external ankle support. Bracing and taping in rugby union. Sports Medicine. 1998, 25 (5): 285-312. 10.2165/00007256-199825050-00001.
Robbins S, Waked E, Rappel R: Ankle taping improves proprioception before and after exercise in young men. British Journal of Sports Medicine. 1995, 29 (4): 242-247. 10.1136/bjsm.29.4.242.
Thonnard JL, Bragard D, Willems PA, Plaghki L: Stability of the braced ankle. A biomechanical investigation. American Journal of Sports Medicine. 1996, 24 (3): 356-361. 10.1177/036354659602400318.
Pedowitz DI, Reddy S, Parekh SG, Huffman GR, Sennett BJ: Prophylactic bracing decreases ankle injuries in collegiate female volleyball players. American Journal of Sports Medicine. 2008, 36 (2): 324-327. 10.1177/0363546507308358.
Sitler M, Ryan J, Wheeler B, McBride J, Arciero R, Anderson J, Horodyski M: The efficacy of a semirigid ankle stabilizer to reduce acute ankle injuries in basketball. A randomized clinical study at West Point. American Journal of Sports Medicine. 1994, 22 (4): 454-461. 10.1177/036354659402200404.
Verhagen EA, van Mechelen W, de Vente W: The effect of preventive measures on the incidence of ankle sprains. Clinical Journal of Sport Medicine. 2000, 10 (4): 291-296. 10.1097/00042752-200010000-00012.
Barrett J, Bilisko T: The role of shoes in the prevention of ankle sprains. Sports Medicine. 1995, 20 (4): 277-280. 10.2165/00007256-199520040-00005.
Rovere GD, Clarke TJ, Yates CS, Burley K: Retrospective comparison of taping and ankle stabilizers in preventing ankle injuries. American Journal of Sports Medicine. 1988, 16 (3): 228-233. 10.1177/036354658801600305.
Tropp H, Askling C, Gillquist J: Prevention of ankle sprains. American Journal of Sports Medicine. 1985, 13 (4): 259-262. 10.1177/036354658501300408.
Junge A, Dvorak J: Soccer injuries: a review on incidence and prevention. Sports Medicine. 2004, 34 (13): 929-938. 10.2165/00007256-200434130-00004.
Mohammadi F: Comparison of 3 preventive Methods to reduce the recurrence of ankle inversion sprains in male soccer players. American Journal of Sports Medicine. 2007, 35 (6): 922-926. 10.1177/0363546507299259.
Verhagen E, Beek van der A, Twisk J, Bouter L, Bahr R, van Mechelen W: The effect of a proprioceptive balance board training program for the prevention of ankle sprains: a prospective controlled trial. American Journal of Sports Medicine. 2004, 32 (6): 1385-1393. 10.1177/0363546503262177.
Stasinopoulos D: Comparison of three preventive Methods in order to reduce the incidence of ankle inversion sprains among female volleyball players. British Journal of Sports Medicine. 2004, 38 (2): 182-185. 10.1136/bjsm.2002.003947.
Scase E, Cook J, Makdissi M, Gabbe B, Shuck L: Teaching landing skills in elite junior Australian football: evaluation of an injury prevention strategy. British Journal of Sports Medicine. 2006, 40 (10): 834-838. 10.1136/bjsm.2006.025692.
Andersen TE, Engebretsen L, Bahr R: Rule violations as a cause of injuries in male norwegian professional football: are the referees doing their job?. American Journal of Sports Medicine. 2004, 32 (1 Supp): 62-68.
Reeser JC, Dick R, Agel J, Bahr R: The effects of changing the centerline rule on the incidence of ankle injuries in women's collegiate volleyball. International Journal of Volleyball Research. 2001, 4 (1): 12-16.
Gabbett TJ: Influence of the limited interchange rule on injury rates in sub-elite Rugby League players. Journal of Science and Medicine in Sport. 2005, 8 (1): 111-5. 10.1016/S1440-2440(05)80031-3.
Hume PA, Steele JR: A preliminary investigation of injury prevention strategies in Netball: are players heeding the advice?. Journal of Science and Medicine in Sport. 2000, 3 (4): 406-413. 10.1016/S1440-2440(00)80007-9.
Timpka T, Ekstrand J, Svanstrom L: From sports injury prevention to safety promotion in sports. Sports Medicine. 2006, 36 (9): 733-745. 10.2165/00007256-200636090-00002.
This study was made possible by equipment/resources donated by The Hong Kong Jockey Club Charities Trust.
The authors declare that they have no competing interests.
DTPF conducted the revise and drafted the manuscript. YYC and KMM assisted in compiling the data and summary. PSHY interpreted the findings and critically revised the manuscript. KMC conceived and coordinated the study. All authors read and approved the final manuscript.
Daniel TP Fong, Yue-Yan Chan, Kam-Ming Mok, Patrick SH Yung contributed equally to this work.
About this article
Cite this article
Fong, D.T., Chan, Y., Mok, K. et al. Understanding acute ankle ligamentous sprain injury in sports. BMC Sports Sci Med Rehabil 1, 14 (2009). https://doi.org/10.1186/1758-2555-1-14
- Ankle Sprain
- Subtalar Joint
- Ankle Instability
- Chronic Ankle Instability
- Lateral Ankle Sprain