Management of ankle injuries in professional basketball players: Prevalence and rehabilitation (2024)

Lateral low ankle sprain

Among all ankle sprains, lateral ankle ligament sprains are reported to be the most common, compromising 80.2% of all ankle sprains among professional basketball players. ¹³ Lateral ankle sprains are also much more likely to be produced by a contact mechanism such as stepping on another player’s foot or general contact with another player (71.2%).¹³ Additionally, professional basketball players younger than 26 years old experience a higher incidence of lateral ankle sprains when compared to players 26 years old or older.¹³ Interestingly, the prevalence of lateral ankle sprains has declined over the past three decades while the prevalence of high ankle sprains has risen.^13,14

Lateral ankle sprains are caused by excess inversion of the ankle joint which creates stress on the anterior talofibular ligament, calcaneofibular ligament, and the posterior talofibular ligament. The severity of the sprain may be rated based upon how much damage these ankle ligaments sustain. The majority of lateral ankle sprains do not require surgical intervention and can be treated nonoperatively. The first step in lateral ankle sprain management is to acutely minimize the degree of swelling and inflammation in the ankle. This is most effectively achieved by employing the RICE protocol (rest, ice, compression, and elevation), particularly for the first 24-48 hours.^15,16 For more severe sprains, such as Grade 2 or 3, immobilization with a wrap or bracing device may also be employed fo the first few days to weeks to minimize pain and further injury. The athlete may implement the use of crutches initially and transition to a walking boot as soon as weightbearing can be safely tolerated.

Lateral ankle sprains are caused by excess inversion of the ankle joint which creates stress on the anterior talofibular ligament, calcaneofibular ligament, and the posterior talofibular ligament. The severity of the sprain may be rated based upon how much damage these ankle ligaments sustain. The majority of lateral ankle sprains do not require surgical intervention and can be treated nonoperatively. The first step in lateral ankle sprain management is to acutely minimize the degree of swelling and inflammation in the ankle. This is most effectively achieved by employing the RICE protocol (rest, ice, compression, and elevation), particularly for the first 24-48 hours.^15,16 For more severe sprains, such as Grade 2 or 3, immobilization with a wrap or bracing device may also be employed for the first few days to weeks to minimize pain and further injury. The athlete may implement the use of crutches initially and transition to a walking boot as soon as weightbearing can be safely tolerated.

Rehabilitation begins with the implementation of proprioceptive training and muscle strengthening at 1-2 weeks post sprain. Closed chain lower extremity exercises can also be done bilaterally at this time. In weeks 2-3 post injury, unilateral closed chain exercises should be implemented along with straight line jogging and running. Braced, sport specific activities can usually be incorporated in weeks 3-4 depending on the severity of the initial injury. Full rehabilitation for moderate to severe sprains is usually accomplished by 6-8 weeks, at which time the athlete can safely return to competition.¹⁷ However, a history of previous sprains in an athlete should be considered as this may increase the likelihood of a subsequent.¹⁸

Medial low ankle sprain

Medial ankle sprains are much less common than lateral sprains, only compromising 7.8% of all ankle sprains in professional basketball players.¹³ Like lateral ankle sprains, medial sprains are also more likely to be caused by a contact mechanism (63.0%). However, medial ankle sprains were the most likely ankle sprain type to be caused by a noncontact mechanism (37.0%).¹³

The medial ankle is primarily supported by the deltoid ligament. Sprains of this ligament are typically caused by excessive eversion and dorsiflexion of the ankle joint. Due to the large biomechanical forces that must be present to cause damage to the deltoid ligament, fibular or medial malleolus fractures may also be present which may lead to a more severe injury that is difficult to recover from.¹⁹ Like lateral ankle sprains, medial sprains are also typically treated nonoperatively. However, if the ankle is chronically unstable, deltoid ligament reconstruction may be required, but this is uncommon. Acutely, the RICE protocol should be used to reduce the amount of swelling, pain, and inflammation in the ankle. An x-ray of the ankle may also be performed to check for coexisting fractures which may need surgical reduction. If no fractures are present, the ankle is usually immobilized with a cast or boot and no weightbearing for the first 1-2 weeks.²⁰

In weeks 2-3, low intensity, low impact exercise may be started (e.g. exercise bike) along with isolated proprioceptive training and light muscular strengthening. Gradually, the use of an elliptical machine may also be incorporated as the athlete progresses and begins to get more range of motion and stability in the ankle. Straight light running is then begun and usually becomes asymptomatic in the first 3-4 weeks. However, sport specific movements such as cutting, planting, and jumping may be painful for months post-injury. Moreover, the use of an ankle stabilizing brace or wrap is also particularly important in an athlete’s return to play. An athlete’s rehabilitation can vary widely with a medial ankle sprain and may take upwards of 3-6+ months.²⁰

High ankle sprain

High ankle sprains are the least common classification of ankle sprain among professional basketball players making up only 4.1% of all sprains. However, they are among the most severe ankle injuries and often result in more missed games and increased time to return when compared to medial or lateral ankle sprains.¹³ The prevalence of high ankle sprains among NBA players has also risen over the past several decades.

High ankle sprains, also known as syndesmotic sprains, involve the disruption of the complex of connective tissue that bridges the tibia and fibula. This syndesmosis provides stability to the mortise of the talocrural (ankle) joint. The mechanism of injury almost universally involves forceful external rotation of the foot and ankle while the leg is in a planted position (e.g. rapid internal pivoting of an externally planted foot). This creates strain on the syndesmosis when the talus generates a separating pressure in the lower tibia and fibula. Unlike medial and lateral ankle sprains, surgical repair of high ankle sprains is more common and may be indicated if a fracture is present or if the syndesmosis is significantly disrupted.²¹ The stability of the syndesmosis should be evaluated on lateral stress radiographs to evaluate for widening of the tibiofibular clear space indicating instability.²¹ Surgical repair of the syndesmosis via either screw fixation or suture button have been shown to have high success rates and may lead to less long term, chronic pain and instability.²²

Whether treated surgically or non-surgically, the rehabilitation process for high ankle sprains is similar. Acutely, the ankle is treated with the RICE protocol and immobilization in a walking boot, cast, or wrap. In immobilization, it is important to stabilize the syndesmosis by limiting external rotation. This period is also accompanied by non-weightbearing or limited weightbearing for 1-2 weeks. Full weightbearing is recommended when the athlete can tolerate ambulation with minimal discomfort. Proprioceptive training and muscle strengthening is also indicated in the acute and subacute phase to facilitate recovery and preserve functional ability. When the athlete can comfortably jog in a straight line and hop with minimal discomfort, sport specific training and drills can be performed with substantial modification in intensity.²² Full recovery can vary substantially among athletes with previous research suggesting 6-8+ weeks until a return to play can be recommended. Chronic pain and instability is particularly common among athletes with previous high ankle sprains which further emphasizes the need for proper management and rehabilitation of these complex injuries.²²

Stress fracture

Overuse injuries such as stress fractures are frequently encountered due to the repetitive stresses that basketball requires. In a study conducted on NBA players between 2005 and 2015, 76 lower extremity bony stress injuries were identified with 55.0% involving the foot and 21.1% involving the ankle or fibula.²³ In this study, a stress fracture resulted in a mean of 25.1 games missed and approximately 30% of athletes were unable to return to their previous level of play post-injury.²³ While stress fractures in the ankle and foot are less common than other musculoskeletal injuries, they can be debilitating injuries and linger for weeks to months if not properly managed and rehabilitated.

Stress fractures are most often caused by overuse of the foot and ankle by engaging in frequent, repetitive motions such as running, jumping, cutting, or pivoting that cause inflammation and microscopic trauma that progresses to a small fracture over time. The most common bones to experience a stress fracture in the ankle are the navicular bone, talus, and the lower tibia and fibula.²⁴ An x-ray is used to diagnose a stress fracture, but these fractures may be difficult to detect. If an x-ray does not show evidence of a stress fracture, but clinical suspicion is strong, MRI or CT scan may need to be performed. In professional basketball players, stress fractures are routinely treated surgically. Conservative management often leads to an increased risk of refracture and surgical treatment typically offers athletes a quicker return to competition. ²³ When a stress fracture is identified, it should be treated acutely with the RICE protocol. Crutches may also be employed in the first 1-2 weeks post-injury. Non-operatively, a stiff soled shoe, walking boot, or orthotic ankle brace should be used to stabilize the ankle and allow the nondisplaced fracture to heal properly and in good position. Further, an orthotic shoe modification may be utilized so that excess stress can be unloaded from the lateral foot and ankle.²⁵ This modification will place the fracture in an optimal biomechanical position to heal and lower the likelihood of a nonunion or further damage. Surgical intervention is typically reserved for failure of conservative management, or among elite athletes such as NBA players, particularly with navicular stress fractures.²⁶ Navicular stress fractures account for 25% of all stress fractures and have a predilection for young, male athletes.²⁶ Studies have shown that navicular stress fractures were slower to heal, had higher nonunion rates, and resulted in a slower return to activity when managed conservatively.^27,28 Surgical treatment in these cases, especially among athletes, is recommended and typically involves screw fixation with a possible bone graft.²⁹ The average return to play after surgical intervention is 3.8 months versus 5.6 months with conservative treatment.³⁰

Bone stimulating devices that employ electromagnetic or ultrasound stimulation may also be incorporated in the healing process either to complement conservative management or post-operatively.³¹ These devices create microscopic mechanical stresses that accelerate bone formation and healing, but evidence is limited on the long term effectiveness.³² Once the ankle pain is completely resolved, strengthening exercises and light activity may be resumed. This includes banded resistance training, low impact exercise, proprioceptive training, and straight-line jogging. However, the gradual reintroduction of activity should span the course of 4-6 weeks. A return to activity too soon may reinjure the ankle and cause the bone to re-fracture.²⁴

It is also worth noting that vitamin D supplementation plays an important role in stress fracture management and prevention. Adequate levels of vitamin D, either through sunlight exposure or exogenous intake in food or supplements, has been shown to decrease the incidence of stress fractures in active individuals.^33–35 A serum 25(OH)D level should be obtained in athletes, especially those with an increased risk of developing a stress. If a deficiency exists, vitamin D supplementation should be given to avoid future injury and promote a quicker recovery if a stress fracture is already present. ³⁶

Jones fracture

There are relatively high rates of Jones fractures among professional basketball players, and they are widely dreaded as they may have profound impacts on an athlete’s ability to return to play. In a study conducted between 1994 and 2013, 37 players were identified who had a confirmed Jones fracture diagnosis, and nearly 15% of them did not return to an NBA game after the season in which the injury was sustained.³⁷

A Jones fracture is defined as a transverse diaphyseal fracture of the proximal fifth metatarsal. This area of the ankle and foot has a limited blood supply which makes recovery complicated and difficult in some situations. Up to 15 to 30% of fractures have a nonunion. Jones fractures are caused when the foot is significantly adducted with a lifted heel. This type of movement usually accompanies abrupt changes in direction.³⁸ X-ray imaging is used to evaluate these fractures and may help the physician determine whether operative or non-operative treatment is required. Follow up with advanced imaging such as CT or MRI may be indicated if bony bridging cannot be adequately appreciated on traditional radiographs.²³ If the fifth metatarsal fracture is nondisplaced, a conservative approach can be taken with 6-8 weeks of non-weightbearing in a short leg cast. However, in displaced fractures or in high level athletes such as professional basketball players, surgical intervention may be the most appropriate treatment in order to accelerate the athletes return to play and to avoid bony nonunion risks or chronic injury.³⁸

Surgical intervention may include the use of intermedullary screw fixation, low profile plating, or tension band constructs.³⁸ In the first week post-surgery, modified weightbearing activities may begin along with general lower extremity body weight exercises like leg lifts. In weeks 2-6, full weightbearing can be started when the athlete no longer experiences discomfort or pain. Follow up x-rays are also important to ensure that the bone is healing properly. During this period, foot and ankle stretching and resistance band training is recommended. In weeks 6-8, light activity and functional weightbearing activities are started, but high impact activity should be avoided. By week 8, sport-specific training can likely begin, but the progression to full activity should be gradual and may vary from athlete to athlete.³⁹

Weber type A fractures

Weber type A fractures are lateral fibular fractures that occur below an intact syndesmosis below the talar dome. Such fractures most often occur as a result of an abduction force upon the supinated foot.⁴² This injury mechanism creates excess tension on the lateral collateral ligaments, resulting in rupture of the lateral collateral ligaments or an avulsion pull-off fracture of the lateral malleolus below the syndesmosis. These injuries are typically stable, with an intact tibiofibular syndesmosis and intact deltoid ligament. As such, these fractures rarely require surgical intervention. However, the force transferred across the ankle may also result in oblique, push off fractures of the medial malleolus and it is important to assess the lateral malleolus via radiographic imaging and deep palpation.

Regarding treatment, any stable Weber type A ankle fracture with non-displaced or minimally displaced avulsion fracture of the distal fibula and no medial lesion upon examination or radiographic evaluation should be treated with a walking cast until the fibula has healed. Athletes with such injuries can usually return to play by 8 weeks. Indications for surgical treatment via Operative Fixation and Internal Fixation (ORIF) of such injuries includes the presence of fracture displacement or significant instability at the lateral malleolus.

Weber type B fractures

Weber type B fractures are lateral fibular fractures that occur at the level of the syndesmosis.⁴² As a result, these injuries result in a partial, or occasionally complete, rupture of the syndesmosis. Such fractures most often occur as a result of forced external rotation on the supinated foot. This injury mechanism is often accompanied by rupture of the anterior syndesmosis, oblique or spiral fracture of the fibula, rupture of the posterior malleolus, and potential avulsion fracture of the medial malleolus. Additionally, the deltoid ligament may be torn. These injuries result in variable stability of the syndesmosis, and adequate workup and assessment of stability is vital to determine treatment.

As the presence of instability may be an indication for operative treatment of such fractures, stress radiographs and manual stress testing should be performed in all cases in which such an injury is suspected. Widening of the distal tibiofibular joint indicates syndesmotic injury and instability, and ORIF is most often performed in such cases. Although the literature is not entirely conclusive regarding optimal treatment for these fractures, it is widely accepted that conservative, non-operative treatment with a walking cast can be pursued in isolated, stable Weber type B fractures if there is less than 3mm of fibular displacement without medial injury.⁴³ Indications for operative treatment include syndesmotic instability as indicated on radiographic or manual stress test, fibular displacement over 3mm, displacement of medial fracture, or deltoid ligament injury often indicated by over 5mm of medial clear space on static radiographs. ⁴³ For unstable but otherwise nondisplaced and isolated lateral malleolar Weber B fractures, recent literature has demonstrated that equivalent outcomes can be achieved with either non-operative or operative management.⁴⁴ In these cases, treatment must be tailored to the individual characteristics and goals of the athlete.

Weber type C fractures

Weber type C fractures are lateral fibular fractures that occur above the syndesmosis, and nearly always are accompanied by a complete rupture of the syndesmosis with resulting instability of the ankle.⁴² Such fractures typically are the result of excessive external rotation on the pronated foot. In addition to the fibula fracture above the syndesmosis, this injury mechanism often causes avulsion of the medial malleolus, rupture of the anterior syndesmosis, and avulsion of the posterior malleolus. These injuries are typically unstable, and nearly always require surgical intervention with ORIF. The literature demonstrates equivalent outcomes may be achieved with or without the additional use of a syndesmotic screw when treating such fractures, and the decision to stabilize the syndesmosis can be made on an individual basis.⁴⁵ It is important to set realistic expectations with athletes requiring surgical repair of these injuries, as recent study indicates that as few as 25% of athletes return to the same level of play after one year following ORIF of unstable ankle fractures.⁴⁶

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