Over the last few decades, several predisposing intrinsic and extrinsic risk factors for acute lateral ankle sprains have been investigated (Table 10.1). The most commonly cited intrinsic risk factors for lateral ankle sprain are previous injury [30–36], poor neuromuscular postural control [31, 37–40], and decreased ankle joint range of movement [41, 42]. Conversely, gender [32, 43], age [30, 33, 43], biometry (height, weight) [30, 31, 33, 36, 44], strength (ankle and hip) [39, 41], and anatomical alignment [33, 44–49] still show conflicting evidence on the scientific literature. Regarding the extrinsic risk factors, improper lace-up of ankle brace [50, 51], third and fourth generation of artificial turf [52, 53], absence of or incorrect warm-up [54], player position [33, 34, 55], time into the game/season (which may be associated with accumulated fatigue) [34], and lack of use of external support have been suggested [36, 56] (Table 10.1).

Ankle sprain has been defined as a morphologic pathological condition of the ankle ligamentous complex, ranging from an overstretching to complete rupture of the ligament [19]. Thus, after an acute ankle supination trauma, it is essential to differentiate a simple sprain from a ligament rupture [57]. In this sense, several grading systems for lateral ankle ligament injuries have been developed, based on the anatomical injury, clinical symptoms, trauma mechanism, stability, and the severity of the injury [19]. In addition, grading of the injury may allow the clinician to better judge the prognosis and design the rehabilitation program [19, 58].

Konradsen and colleagues [59] proposed, in 1991, a severity classification system grouped into three grades according to the injury severity: mild (grade 1), moderate (grade 2), and severe (grade 3). This classification is easily reproducible and should be applied 5 days after the injury (Table 10.2) [59].

However, when dealing with elite athletes, providing a precise prognosis as soon as possible plays a crucial role, as time to return to competition is a determinant factor. Thus, Malliaropoulos and colleagues [60] proposed a simple grading system for the severity of acute lateral ankle sprains in athletes based in accurate objective criteria (Table 10.3).

In addition, a functional classification of ankle sprains, based on the patient’s ambulatory ability, may also be made (Table 10.4).

When considering the ankle joint stability, two types of instability may be considered [14, 61]:

Chronic ankle instability implicates the occurrence of repetitive bouts of episodes of lateral ankle instability, resulting in numerous ankle sprains, associated with biomechanical instability [14].

Dynamic ankle joint stiffness, defined as passive and active resistance of the joint structures (muscles and other soft tissues which cross the ankle joint), generating a net joint moment response [62], should also be considered when assessing ankle stability. It has been suggested that there may be an optimal volume of stiffness that allows the player’s performance with lower risk of injury, taking into account the type of activity or task, gender, and the degree of muscle activation [63–65]. In this sense, increased stiffness may be associated to bony injuries, as decreased stiffness might be correlated with soft tissue injuries. Nevertheless, increased stiffness has been advocated to yield clinically relevant benefits toward performance, diagnosis, and injury prevention programs [63, 65, 66].

Lateral ankle sprain is known to be the most frequent traumatic sports-related ankle injury. The correct diagnosis and accurate subgrouping of the patients are essential for the treatment success. In this sense, it is important to exclude all differential diagnosis including fracture, high ankle sprain, cuboid syndrome, medial ankle sprain, and osteochondral lesion [58]. In addition, neural, muscular, and vascular structures should also be assessed [67].

Usually, a comprehensive medical history taking and an accurate physical examination are enough to the diagnosis of an acute lateral ankle sprain [67]. Performing the physical examination in an acute setting is not recommended, once the results may be unreliable and once the results may be biased or limited due to ankle mechanical pain [57]. It has been reported that delayed physical diagnostic examination (within 4–5 days post-injury) provides better diagnostic accuracy, with high sensitivity and specificity values (96% and 84%, respectively) [68]. Hence, physical examination should be performed as soon as the athlete’s swelling and pain have decreased, and it has been confirmed that the etiology of the swelling is edema or hematoma [57]. The physical examination must include inspection of the ankle complex, palpation of the ATFL (Fig. 10.2), the talar inversion tilt test, and the anterior drawer test (Fig. 10.3), and a few considerations may be made regarding the lateral ankle ligaments rupture [57, 69]:

When assessing athletes with suspicion of ankle lateral ligamentous injury, in addition to the considerations above, the clinician should also assess the ankle and subtalar joint range of motion, ligamentous mechanical laxity, muscular strength, and functional performance (such as single-limb balance, star excursion balance test, and hop tests) [58, 60, 67]. In addition, several outcome instruments [70–75] may be used to further qualify the lateral ankle joint status (Table 10.5).

Diagnostic physical examination is known to be dependent of the clinician’s sensitivity and experience [76]. Hence, several mechanical testing devices have emerged as a potential instrument to objectively measure the ankle ligamentous laxity [77–83].

After a lateral ankle sprain, if there are recurrent episodes of giving away and/or “feelings of instability,” the clinician should suspect of the development to chronic ankle instability [13, 14]. In this sense, the chronic ankle instability may be subgrouped into biomechanical (mechanical and functional) instability, or even the presence of both types of ankle instability [84]. By subgrouping the patients into different categories, the clinician may tailor the rehabilitation protocol in accordance to the specific deficits associated with the type of instability and personalize it in order to address each player’s needs and expectations.

When dealing with athletes with an acute lateral ankle trauma, radiography is of upmost importance to exclude the presence of any ankle fracture [19]. In this sense, the Ottawa and Bernese ankle rules may be used as criteria to exclude ankle fractures; however, the Ottawa ankle rules seem to be more reliable [85, 86].

Stress radiography has no role in the routine diagnosis of acute lateral ankle ligament injuries [19]. In addition, during the acute setting, performing stress radiography evaluation may appear difficult due to pain, edema, and muscle spasms [87]. This diagnostic tool is able to measure the soft tissue structures’ passive stiffness and identify the presence of increased laxity within the talocrural and subtalar joints (Fig. 10.4) [88, 89]. Hence, it provides the possibility to further characterize the ankle instability and better direct the treatment.

Magnetic resonance imaging (MRI) may be useful to assess the integrity and morphology of the lateral ankle ligamentous complex and its peripheral tissues (Fig. 10.5) [67]. In addition, it has a valuable role in the differential diagnosis of osteochondral lesions, tendon disorders, and occult fractures [90, 91]. It has been suggested that performing the imaging studies with resort to superficial coils and with the ankle at 20 degrees of flexion improves the ligament visualization [19]. Nevertheless, osteochondral lesions may be better identified using computed tomography (CT) [19]. Moreover, CT scans may be useful to assess the articular surface, abnormal osseous anatomy, and avulsion fractures [92].

The ultrasound is able to provide a detailed and accurate depiction of the normal ankle’s anatomic structures and ligament integrity [93]. In which concerns ankle ligament ruptures, it has high sensitivity (92%) and moderate specificity (64%), with positive and negative predictive values of 85 and 77%, respectively [76, 94]. Although stress ultrasonography may cause some discomfort and requires some level of expertise, it may augment the accuracy of the diagnosis [19, 95].

It has been discussed over the past decades which treatment approach provides better outcomes after an acute lateral ankle ligament injuries. In this sense, Kekhoffs et al. [96] performed, in 2007, a Cochrane systematic review of randomized control trials (20 randomized control trials and 2562 patients included) assessing the surgical versus conservative treatment for acute injuries of the lateral ligament complex of the ankle in adults. The authors found no statistical significant superiority in which concerns the two treatment approaches. More recently, two randomized control trials also compared the surgical treatment against functional treatment, showing, likewise, no clear superiority of one approach over the other [97, 98]. Thus, the decision between surgical and conservative treatment must be on an individual basis, taking into account the relative benefits and risks of each treatment approach [96], as also, other relevant sports-related features, such as athlete’s individual and team expectations, time into the season and/or career, expected ankle load, medical history, time since the trauma/injury, and concomitant injuries [99].

Several plausible advantages in favor of primary repair of acute lateral ankle ligaments’ rupture may be enunciated, such as enhanced ligament healing, reduced layoff days from training/competition, inferior rate of recurrence episodes, and lower risk of developing chronic ankle instability [98, 100]. In addition, surgical repair provides better objective stability to the ankle joint (positive talar tilt on stress radiographs or positive anterior drawer sign) [19], which plays a crucial role in the elite athlete.

When considering elite athletes, expert consensus (level V) [19, 69] suggests the surgical treatment as a primary approach once it provides a better chance in maintaining the ankle joint stability. In addition, it has also been recommended that the surgical repair of acute lateral ankle ligaments injury should be performed by an experienced surgeon, once it will likely improve the outcomes [19, 101, 102].

Since its first report in 1932 by Nilsonne [103], ankle ligament surgery has been gaining its place in the orthopedic and traumatology community (specially within the sports medicine scope), and dozens of new techniques have been developed [104].

In relation to ankle ligament surgery, two main approaches appear: anatomic and nonanatomic reconstruction. The nonanatomic reconstruction using local tendons has been proposed; however, it can lead to functional and mechanical instability, restricted ankle range of movement, subtalar and tibiotalar stiffness, higher rate of reoperations, development of chronic pain, degenerative joint disease changes, and impaired sports performance [105–110]. The anatomic reconstruction (Fig. 10.6) usually provides good long-term outcomes in which concerns stability, decreased symptomatology, and functional ability [111–114]. In this sense, the Broström procedure, along with its modifications, has been accepted and has the gold standard procedure to surgically treat lateral ankle ligament injuries [57, 115]. In addition, anatomic reconstruction with tenodesis augmentation with autograft or allograft tissue (usually from the hamstrings) has been proposed, with good results [116–119]. In fact, it has been demonstrated that anatomic reconstruction of the ATLF with semitendinosus allografts provides similar strength and stiffness as the native ligament at time zero in a fresh-frozen cadaveric model. This approach is clearly useful in clinical situations where a Broström repair is unlikely to be successful or has previously failed [120]. Additionally, it may be considered a suture-tape augmentation of ATFL [121, 122], once it is at least as strong and stiff as the native one at time zero in a cadaveric model [121]. Moreover, other modified techniques have emerged to address the specific needs of high-demanding athletes [123, 124].

More recently, arthroscopic techniques for repair of the lateral ankle ligaments (Fig. 10.7) have been gaining increasing interest as they provide an improved diagnosis of the lesion diagnosis, also reduce the surgical aggression, and shorten the rehabilitation process [57, 125, 126]. In this sense, and along with the development of novel anchor and fixation devices, several arthroscopic techniques have been developed to repair the lateral ankle ligaments [125, 127–140]. However, there is still limited evidence to support the arthroscopic repair since most available studies are either technical notes or case series (level IV and V) [141]. Nevertheless, biomechanical cadaveric studies comparing open vs arthroscopic approach for lateral ankle instability found that the minimal invasive approach provided an effective ankle stabilization, and, therefore, a minimally invasive, arthroscopic approach may be deliberated for the treatment of lateral ankle instability [142, 143]. In addition, ESSKA-AFAS Ankle Instability Group consensus opinion suggests that the arthroscopic anatomical reconstruction of the lateral ankle ligaments is feasible and reproducible procedure if performed by an experienced surgeon used to the arthroscopic techniques [144].

When dealing with athletes, a direct anatomic repair of the ruptured ligaments by an expert ankle/sports surgeon in order to provide the best surgical approach without compromising or delaying return to competition is suggested [145].

The rehabilitation following ankle ligament surgery in athletes usually involves some controversy due to the conflict between the athlete safety concerns and the return to play as soon as possible. In the postsurgical phase (10–14 days), the athlete’s ankle is immobilized. After wound inspection, it is allowed for the patient to walk in full weight-bearing while using a walker boot. However, walking without any protection should not be allowed until the sixth week. In the early rehabilitation phase (6–10 weeks), the athlete is allowed to walk with any support, and the rehabilitation goals include increased muscular strength and lower limb range of motion, restored full ankle/foot active range of motion, and improved gait symmetry. To progress to the late rehabilitation phase (8–12 weeks), the athlete should be able to walk with turns without pain, good static balance, and at least 90% of muscular strength compared to the contralateral side. At this phase, the muscular strengthening is performed unilaterally, and rehabilitation goals are based in the balance and functional performance improvement. As soon as the athlete demonstrates good ankle functional performance (functional tests at least 90% compared to the contralateral side), the athlete progresses to the sports-specific training phase, which is usually between the 12th week and the 14th month. In this last phase, the athlete returns to running and agility exercises, as sport-specific drills are added to the rehabilitation [146].

Conservative management of lateral ankle ligament injuries is based on the early functional rehabilitation focusing on the controlling of clinical symptomatology and restoration of the neuromuscular deficits (such as proprioceptive deficits and peroneal muscle latency [147, 148]). In this sense, the early rehabilitation should include the PRICE protocol (protection, rest, ice, compression, and elevation), early range of movement exercises, progressive weight-bearing and peroneal strengthening, and proprioceptive training [87, 149–151].

In the healing phase, the PRICE protocol helps to control the clinical symptomatology (specially pain and swelling). The cryotherapy should be performed intermittently and may be applied through immersion or direct approach [152, 153]. The application of ice with nonsteroidal anti-inflammatory medication may enhance a faster healing [150].

Progressive early weight-bearing with support has shown to have significant clinical and functional benefits and cost-effectiveness in the treatment of acute lateral ankle sprains [154–156]. During the healing phase, the use of crutches or other walking supports may prevent the occurrence of reinjury and reduce the pain during walking, providing improved conditions to the athlete and the rehabilitation exercises [67].

Short-term plaster immobilization or similar rigid supports (± 10 days) in the acute healing phase may provide a hasten decrease on pain and swelling [69, 157]. Nevertheless, a 4–6-week functional treatment is preferable [69, 158, 159]. Several external ankle supports have shown to be helpful in the treatment of acute lateral ankle sprains [160, 161]. Within this scope, lace-up ankle orthosis has shown better results than semirigid ankle support, elastic bandage, and tape [161] and should be recommended [69].

Therapeutic exercises should be added to the treatment plan and should be tailored to increase ankle range of motion, strengthen the peripheral muscles, and restore the neuromuscular deficits [162–168]. Trunk and hip strengthening exercises may also be included in order to address potential hip strength deficits and consequently reduce the risk of reinjury [39, 58]. In addition, the incorporation of early manual therapy, such as articular mobilization, soft tissue massage, and lymphatic drainage, may be helpful in decreasing the joint stiffness and swelling, as well as increase the ankle range of movement [163, 169–171]. Correcting ankle joint malpositions in pre-landing to post-landing stages will improve muscle recruitment and co-contraction, enhancing the ankle dynamic postural control in patients with chronic ankle instability [172].

In which concerns the use of physical agents, the scientific literature provides conflicting evidence regarding electrotherapy [173–175], low-level laser therapy [176, 177], and therapeutic ultrasound [178] and therefore are not recommended for acute lateral ankle sprains. Pulsating shortwave diathermy seems to be beneficial in decreasing edema and associated gait deviations [179].

Sports-specific training is important and should be included in the more advanced phase of ankle ligament injuries’ rehabilitation [67]. This sports-specific training should focus to the reestablishment of mobility, strength, and coordination while performing the sport-specific exercises [58, 146].

One of the bases to design a prevention program is a comprehensive and accurate screening of the athlete’s biomechanical performance. This initial screening will allow the physiotherapist to identify the athletes at risk of sustaining an ankle ligament injury and measure potential neuromuscular, proprioceptive, and ligamentous laxity deficits. As soon as the modifiable risk factors are identified, the physiotherapist should focus on correcting those impairments to prevent future injury/reinjury. Even after a successful return to the competition, the athlete should continue with his prevention exercises in order to prevent further damage, recurrence of the injury, or new injuries (secondary prevention). In this sense, the follow-up screening is crucial to measure the effects of the preventive strategies and keep tailoring the prevention program to address each athlete’s individual deficits.

Several preventive strategies have been suggested in the scientific literature. The use of brace to prevent an inversion injury is recommended, and different systematic reviews have shown to be an effective strategy [160, 180, 181]. Although exercise therapy shows conflicting evidence in the literature [39, 163, 180, 182–187], the implementation of balance and coordination training within the preventive programs is recommended [69].

These prevention programs are proven to be cost-effective and able to reduce the associated cost of €69 and €332 for non-injured and injured athletes, with an overall €35.9 million reduction per year in the Netherlands [183]. Thus, promoting adherence and compliance strategies to these prevention programs is of upmost importance.

Tibiofibular syndesmotic injuries are also known as high ankle sprains. Compared to the lateral ankle ligament injuries, tibiofibular syndesmotic injuries are rare once they require higher loads to fail [87]. Several injury mechanisms have been described; however, the most common involves hyperdorsiflexion and external rotation of the ankle [188], which can also injure the deltoid ligament [189]. In football, the injury mechanism usually involves (1) quick internal twist of the externally rotated foot with lateral impact on the leg or (2) external lateral trauma to the lower leg (proximal to the heel), forcing the footballer ankle to external rotation [190].

The ESSKA-AFAS consensus panel has provided a definition to isolate syndesmotic injuries as “injury of one or more ligaments of the tibiofibular syndesmosis with or without the association of the injury of the deltoid ligament” [191]. Moreover, they classified these injuries based on the time from injury, as it affects the management:

In addition, a distinction between total and partial rupture of the syndesmotic ligament is crucial [192]. Medical history may assist in determining the extent of the injury [57]. Physical examination involves palpation of the membrane interossea, and manual test includes cotton test, dorsiflexion-compression test, external rotation stress test, fibular translation, palpation test, and squeeze test [191]. If the pain and swelling extend proximally through the interosseus membrane, an unstable ankle mortise should be suspected, since they have direct correlation [192]. Nevertheless, in the acute setting, the diagnosis may be difficult since 40% of the patients may also present pain on the anterior distal talofibular ligament with no rupture of the syndesmotic ligaments [193]. The MRI provides high sensitivity (95%) and specificity (90%) figures [190, 194] and may be reliably used in the diagnosis and prognosis of syndesmotic ligament injuries in football players [193]. Stress ultrasonography may be considered as it provides a cheaper and faster examination [195].

The ESSKA-AFAS consensus panel [196] recommends that acute isolated syndesmotic ruptures with rupture of the anterior-inferior talofibular ligament, with or without interosseus ligament, and with an intact deltoid ligament should be treated conservatively: non-weight-bearing with initially rest, cryotherapy, and walker boot (3 weeks). Following these for 3 weeks, proprioceptive training, strengthening, and mobility exercises should be included into the conservative treatment [196, 197]. Acute syndesmotic injuries with deltoid ligament rupture (unstable) should be treated surgically [196]: screw fixation, dynamic fixation with a suture button, or direct repair of the anterior inferior talofibular ligament with or without suture anchors/button [196, 197].

Isolated deltoid ligament injuries are uncommon and mostly associated with lateral malleolar and fibular fractures [198]. The primary mechanism of injury mainly involves eversion or external rotation of the ankle, which in athletes usually occurs during an off-balanced, pronated foot landing [199]. This injury is often associated with anteromedial pain instead of recurrent medial ankle instability [57]. Hintermann et al. [200] classified these injuries into three grades based on the location and severity of injury (Table 10.6).

Radiography should include anteroposterior, mortise, and lateral views, providing moderate sensitivity (57%) and specificity (60%) [201]. On the other hand, MRI provides high sensitivity and specificity figures to superficial and deep deltoid ligament layers [202], with clinical use at the acute setting [198]. In addition, ultrasonography has high diagnostic accuracy, with 100% sensitivity and specificity reported [201]. CT scans may be used in cases with associated fracture or avulsion or when bony morphology is unclear on radiographs or MRI [198].

Isolated superficial deltoid ligament injury may be treated with short-term immobilization and rehabilitation program similar to the one discussed for lateral ankle ligament injuries [198, 203]. Acute and chronic deltoid ligament injury and deltoid ligament insufficiency may be treated surgically through direct repair or reconstruction, once it might provide an early stabilization and anatomical reduction of the talus and, therefore, facilitate the early rehabilitation [198, 203].