Ankle sprain

What is an ankle sprain ?

The ankle is very vulnerable at the beginning of the weight-bearing phase, because it depends on the angle of presentation to the ground during the heel strike and is not protected at this time by muscle action. Ankle sprains are traumatic injuries affecting the ankle ligaments, approximately 77% of which are located in the lateral compartment (External Lateral Ligament composed of 3 bundles) (1). In these sprains, 73% involve a tear or rupture of the anterior bundle (2).

There are 3 stages of this lateral sprain : 

• Stage 1: simple ligament distension 
• Stage 2: rupture of the anterior bundle and damage to the middle bundle 
• Stage 3: rupture of the anterior and middle bundles, possible involvement of the posterior bundle. 

The importance of the Ottawa criteria (3) : 

These criteria, to be applied to any ankle sprain, avoid unnecessary radiology if the patient does not show signs referring to a possible fracture. This avoids overloading imaging centres and, more importantly, avoids a dose of X-rays. If one of the following criteria is positive, an X-ray can be performed: 

• Inability to take 4 steps, immediately after the trauma or during the examination
• Pain in the lower 6 cm of the medial or lateral malleolus
• Pain at the base of the 5th metatarsal (styloid process) 
• Pain in the navicular bone 

In almost all sprains, instability is observed, resulting in a lack of proprioception due to a disturbed nervous system and spinal reflex (4). This lack of stability can be explained by poor pre-activation of the long and short fibular muscles, thus limiting their ability to lock the ankle in variable situations. This lack of pre-activation can become pathological and lead to chronic instability and new opportunities for accidents (5).

How to treat it ?

Immediate treatment :

Various protocols have been developed in recent years for the direct treatment of sprains without proving 100% effective. However, there are some basic steps to take to optimise the treatment of a sprain. 

• Stop the activity so as not to aggravate the lesions already present !
• Elevate the leg so that it is higher than the level of your heart 
• Apply compression (bandage or other) to minimise the initial swelling 
• Apply ice for 15 to 20 minutes (after this time there is no effect) and repeat several times a day to reduce the pain. 
• Painkillers if necessary but not anti-inflammatory drugs. It is important not to take anti-inflammatory drugs, as they can alter or even suppress the natural healing process of the human body (4).
• Consult a doctor and a physiotherapist !

What rehabilitation and treatment ?

The main objectives are the full recovery of function, the prevention of recurrence and the prevention of chronic ankle instability. The latter can be defined as persistent pain or swelling, accompanied by a lack of proprioception and repeated sprains lasting at least 12 months after the initial injury episode. Therefore, the earliest possible treatment is necessary to optimise the time to return to the field. 

Regarding the treatment itself, the main objective will be to move to functional and weight-bearing work as soon as possible depending on the patient. Thus, supervised exercise programmes are preferable to passive modalities as they stimulate the recovery of functional stability of the joint(4). Strengthening of the fibular and posterior tibial muscles should also never be neglected as they work in synergy with the lateral collateral ligaments. 

These programmes must be complemented by manual mobilisations and manipulations, whether active or passive (decoaptations, mobilisations of the bones of the foot and ankle, amplitude gains, stretching…). It was also explained that proprioceptive rehabilitation with a support (strap, tape, etc.) would accelerate the progression of exercises and increase the level of difficulty more quickly, thus optimising rehabilitation. It should also be noted that a delay in the response time of the fibular muscles has been detected, probably due to a traction lesion of the peroneal nerve (6). It is also advisable to take into consideration the muscle response time during rehabilitation. 

Surgery should be reserved for cases with chronic instability that do not respond to comprehensive exercise-based treatment. High level athletes can also have recourse to surgery in order to reduce the time of unavailability. 

Finally, different techniques such as ultrasound, electrotherapy or laser therapy are subject to varying opinions and conclusions about their use in ankle sprains. It is therefore important to keep a critical and nuanced view as some studies approve their effects while others demonstrate their ineffectiveness (7)(8)(9). Each practitioner must therefore base his or her opinion on the experiences of his or her treatments, but also on those of his or her patients. 

How can ankle sprains be prevented in this case ?

The prevention of ankle sprains is mainly based on training in coordination, balance and strengthening the stabilising muscles (long and short fibular). Thus, exercise therapy has been shown to significantly reduce the risk of functional instability leading to injury. However, one should not forget the strengthening of the posterior tibial which has an essential role in controlling the eversion-inversion of the foot. It works in synergy with the fibulars and contributes to the positioning of the heel in space prior to foot contact with the ground (10).

When athletes with recurrent sprains are exposed to high quality proprioceptive training to improve joint position perception, their risk of sprain recurrence is reduced to the same level as healthy controls (4). This training should be included as much as possible during club sessions or at home in order to stimulate the sensory receptors of the ankle as much as possible. 

Another risk factor that should never be neglected is the lack of amplitude in dorsal ankle flexion (11)(12) which can induce an inversion or eversion component of the foot if this amplitude causes a limitation in movement. This adaptation can thus lead to traumatic sprains. It should also be noted that good mobility of the forefoot allows for better adaptation and stability of the ankle, also limiting the risk of injury. 

In the field after an injury, a specific bandage or a kinesiotape can also be beneficial in order to avoid a new trauma. However, they should be avoided in the long term in order to maintain effective intrinsic proprioception of the ankle. 

In short : 

• Functional and proprioceptive work ++
• Strengthening of the stabilising muscles of the ankle 
• Work on amplitude in dorsal flexion (standard at 10-15° in relation to the reference position) 
• Mobilisation of the foot joints

References :