Chronic ankle instability: mechanical or functional?

An ankle that gives way on a kerb, six months or six years after the sprain. The patient says it “lets go”, the examination sometimes finds nothing, and the physiotherapist prescribes proprioception. This page deals with what happens after the sprain, when it recurs: for the management of the acute sprain itself, from the Ottawa rules to the PEACE & LOVE protocol, it is the lateral ankle sprain that should be read. Here, one question alone governs all the rest, and it is badly framed in practice: is this instability mechanical, functional, or simply perceived ?

A synthesis written from primary sources verified one by one on PubMed: identifier resolved through the E-utilities API, journal, year and author list checked, abstract read before citation. Every figure carries its source at the point where it is written. Full bibliography at the end of the article.

In brief: clinical summary

What are the fundamentals to know about chronic ankle instability?

Before treating, you have to know what you are talking about. The term chronic instability in fact covers an entity defined by consensus, a frequency whose estimate depends on the grid used, and joint consequences that go well beyond functional trouble.

What exactly are we talking about?

Chronic ankle instability, in the English-language literature chronic ankle instability or CAI, means the state of a patient more than twelve months from their initial lateral sprain, who has a tendency to repeated sprains, frequent episodes of giving way or a sensation of instability, and persistent symptoms: pain, swelling, limited mobility, weakness, and reduced function as reported by the patient themselves.2

Three elements of that definition deserve emphasis, because they are commonly skipped in practice. The first is the twelve-month interval : a painful, unstable ankle three months after a sprain is not chronic instability, it is a sprain still recovering. The second is repetition : a single episode of giving way is not enough. The third is the most important: the definition explicitly includes patient-reported function, which means that a questionnaire is not an administrative extra, it is a constitutive criterion.

How many sprains progress to chronic instability? The question is badly framed

This is the figure everyone quotes, and it is the one to handle with the greatest care. Depending on the source consulted, you read that 10 to 20 %, 20 to 30 %, or up to 40 % of sprains progress to chronic instability. Those figures do not contradict each other: they are not measuring the same thing.

The Cochrane review devoted to interventions for chronic ankle instability gives a range of 10 - 20 % after an acute sprain.21 The international consensus of ESSKA and AFAS retains 20 - 30 %.25 The reference model of Hertel and Corbett estimates that up to 40 % of people who have had a first sprain will develop chronic instability.2 And the systematic review by Lin and colleagues, which brought together nine studies and 3,804 participants, gives a prevalence of 25 % in an active population (range 7 to 53 %), which rises to 46 % in people with a history of sprain (range 9 to 76 %).4

One piece of work makes it possible to understand where that gap comes from, because it applies two grids to one and the same population. Koshino and colleagues assessed 470 Japanese university athletes. Applying the inclusion and exclusion criteria of the International Ankle Consortium, as they are designed for research, prevalence is 10,0 %. Applying only the inclusion criteria, which corresponds to the way you reason in the clinic, it is 19,8 %.5 Double, without a single subject having changed.

The gap between 10 % and 46 % does not tell of different populations. It tells of different definitions applied to the same ankles.

What the unstable ankle costs in the long run

What is at stake is not only comfort. The lateral sprain is the commonest ankle sprain, and the meta-analysis of 181 prospective studies puts its incidence at 13.6 per 1,000 exposures in women against 6.94 in men, indoor and court sports being the most exposed.9 On that volume, the proportion that tips into chronicity represents a considerable population.

Two documented consequences justify treating it seriously. The first is intra-articular : in a series of 179 ankles operated on for chronic lateral instability, associated lesions were found in 54.7 % of cases, dominated by soft tissue impingement (43.6 %) then osteochondral lesions (15.1 %).7 It should be noted that this series describes ankles that were operated on, and therefore selected: the figure does not transfer as it stands to unstable patients as a whole.

The second is post-traumatic osteoarthritis. Ankle osteoarthritis affects about 1 % of the population, and differs from knee and hip osteoarthritis in that it is secondary to previous trauma in more than 75 % of cases. It also affects a younger, active population, with marked social and occupational consequences, and instability is among the mechanical factors clearly associated with its development.8 The link between chronic instability and osteoarthritis is also noted in the epidemiological synthesis by Herzog and colleagues, which treats the acute sprain, chronic instability and post-traumatic osteoarthritis jointly as the three stages of one trajectory.10

Mechanical or functional instability: what does the distinction change?

This is the chapter that governs all the others. Two patients describe exactly the same complaint, “my ankle gives way”, and warrant different management. What separates them appears neither in the history nor in the questionnaire: you have to go and look for it.

Two mechanisms, three components

The distinction is an old one and it is robust. As early as 2002, Hertel's synthesis on the functional anatomy and pathomechanics of lateral instability held that chronic instability may arise from mechanical instability, from functional instability, or most often from a combination of the two. Mechanical instability refers to objectifiable insufficiencies: pathological laxity, arthrokinematic changes, synovial irritation, degenerative changes. Functional instability refers to insufficiencies of proprioception and neuromuscular control.11

The contemporary reading adds a third term, and it is not an academic refinement. For Wenning and Schmal, chronic instability results from the interaction of three contributing factors: mechanical instability, functional instability and perceivedinstability. The three are not on the same footing: the perceived component is what the patient reports, the other two are what causesit. Deciding on the most appropriate therapeutic option therefore means establishing which of the two main aetiologies, functional or mechanical, dominates the trouble experienced.6

The perceived component is not a psychological residue to be got rid of: it is what the patient reports, it is what the validated questionnaires measure, and it is what the diagnostic criteria themselves rest on. A patient can have frank laxity and feel stable; another can have no laxity at all and no longer dare step off a kerb.

What the distinction means in practice

The most useful sentence in the recent literature on this subject is also the most uncomfortable for our practice: it is becoming increasingly clear that a certain degree of mechanical insufficiency cannot be compensated for by functional training. The point of the differential diagnosis is precisely to identify those patients and offer them the appropriate mechanical therapy: adhesive taping, an ankle brace, or surgical ligament reconstruction.6

That does not mean exercise is useless in the patient with frank laxity: conservative treatment remains the standard of care, and it includes sensorimotor training, strengthening of the periarticular muscles, balance work, and walking and running on varied surfaces. It means that faced with a patient who is not progressing despite a well-conducted programme, the hypothesis to examine first is not “they have not done enough” but “perhaps their mechanical component dominates”.

A patient who does not respond to proprioception is not necessarily a patient who has not done enough of it.

The problem nobody solves: quantifying the mechanical component

One has to be honest about the limit. Quantifying mechanical instability remains a challenge in the clinical approach to this condition. The best established procedure for diagnosing it is physical examination, but that does not allow the deficit to be quantified. The complementary options are stress ultrasound, three-dimensional stress MRI, ankle arthrometry and three-dimensional marker-based motion analysis. Diagnostic arthroscopy is regarded as the reference, but it is invasive, it is not performed for a purely diagnostic purpose, and it grades instability no better.6

The size of the gap between what the examination predicts and what the joint contains has been measured recently. In 179 patients operated on arthroscopically for chronic lateral instability between 2020 and 2024, agreement between the preoperative diagnosis, based on clinical examination and MRI, and the intraoperative findings is poor: kappa of 0.08, for absolute agreement of 24.2 %.7 Three ankles in four did not contain exactly what the examination had announced.

That figure calls for two comments. First, it concerns a population selected for surgery, in whom subtle lesions are over-represented: it does not transfer to the ordinary clinic. Second, it does not say that clinical examination is useless: it says that it is not enough to establish the lesions present, which is very different. For the physiotherapy decision, clinical examination and questionnaires remain the relevant tools, because the decision concerns rehabilitation, not the surgical procedure.

How do you make the diagnosis with criteria rather than an impression?

Chronic instability is one of the few diagnoses in our field to have operational criteria published by international consensus. Applying them turns a subjective complaint into a structured picture, and makes it possible to say which patient you are dealing with.

The International Ankle Consortium criteria

The International Ankle Consortium published a position statement in 2014 intended to standardise patient selection in research, faced with the finding that heterogeneous inclusion criteria limited the generalisability of results.1 The text was reproduced in three journals, the Journal of Orthopaedic and Sports Physical Therapy in 2013 then the Journal of Athletic Training and the British Journal of Sports Medicine in 2014, which shows the intention to disseminate it.

Those criteria were designed for research, and that matters: applied to the letter, they exclude clinically unstable patients, which is exactly what Koshino's comparison made visible.5 Their author acknowledges it in his conclusion: standard criteria may not capture the whole clinical population. In the clinic, they therefore serve as a framework and not as a barrier.

The questionnaires: which one, and at what threshold?

Three instruments are recommended by the consortium to establish subjective instability: the Ankle Instability Instrument, the Cumberland Ankle Instability Tool and the Identification of Functional Ankle Instability.4 The CAIT is the most used in practice, because it is short and produces a continuous score from 0 to 30, so it can be followed over time.12

One point deserves attention because it is a source of confusion. The threshold historically quoted is 27 or less; the threshold used by the consortium in its selection criteria is 24 or less; and a recalibration published in 2014 on two datasets proposes 25 or less, with a sensitivity of 96.6 % and a specificity of 86.8 %, a positive likelihood ratio of 7.3 and a negative one of 0.04.14 Its authors explicitly recommend using that recalibrated threshold to distinguish groups with and without chronic instability. In practice, what counts most is not the threshold chosen but the fact of recording the score and repeating it : individual variation under treatment is more informative than crossing a boundary.

The FAAM deserves particular mention for French-speaking practice: its French version was the subject of a validity and reliability study published in 2011, which makes it a tool that can be used directly with no in-house translation.15 It does not replace the CAIT, it complements it: the CAIT says instability, the FAAM says function, and the two do not move together.

What physical examination can and cannot do

The benchmark meta-analysis on the diagnostic value of clinical ankle tests brought together 14 studies and 6,302 observations. Its conclusion is clear: no test reaches both 90 % sensitivity and 90 % specificity. Palpation of the anterior talofibular ligament is highly sensitive, 95 to 100 %, but very unspecific, 0 to 32 %: it serves to rule out, not to confirm. The anterior drawer, across 6 studies and 885 observations, conversely has a low sensitivity of 54 % (95 % CI: 35 to 71 %) and a high specificity of 87 % (95 % CI: 63 to 96 %): it serves to confirm, not to rule out.17

The practical consequence is direct, and it is worth writing down: a negative anterior drawer does not exclude mechanical laxity. With a sensitivity of 54 %, it misses nearly one in two. Concluding “the drawer is negative, so it is functional” is a reasoning error, and it is probably the commonest error in this field.

What really happens in an unstable ankle?

The word “proprioception” is used so often that it ends up meaning nothing. It nevertheless covers deficits that are measured, quantified, and whose distribution is instructive: they are not where intuition places them.

The proprioceptive deficit is real, and it is local

The most complete meta-analysis on the subject examined 7,731 references, retained 30, and meta-analysed 21. It separates two dimensions of proprioception: kinaesthesia, that is the perception of movement, and joint position sense. Compared with healthy subjects, unstable patients show deficits in kinaesthesia in inversion (effect size 0.64) and in eversion (0.76), and deficits in active joint position sense in inversion (1.00) and in eversion (4.82). Compared with their own healthy side, the deficits exist too: kinaesthesia in inversion (0.41) and in plantarflexion (0.92), active and passive joint position sense in inversion (0.92 and 0.72).13

The most interesting result of that work is the one you do not expect: the proprioceptive deficits of the knee and shoulder of the same patients are not statistically significant. In other words, chronic ankle instability is not the local expression of a global proprioceptive deficit. It is a joint-specific deficit, consistent with damage to the mechanoreceptors and the deafferentation that follows ligament injury. That point has a direct consequence for the content of sessions: the work must be loaded on the injured ankle, not diluted in a general balance programme.

Postural control, and what happens above the ankle

Hertel and Corbett's updated model organises these observations. It describes eight interacting components: the primary tissue injury, pathomechanical impairments, sensory-perceptual impairments, motor-behavioural impairments, personal factors, environmental factors, interactions between components, and the spectrum of clinical outcomes. The whole is set against the biopsychosocial model, the notions of self-organisation and perception-action cycles from dynamical systems theory, and a patient-specific “neurosignature” derived from the neuromatrix theory of pain.2

That framework justifies going beyond the strict joint perimeter. A meta-analysis of nine randomised trials and 306 participants assessed hip strengthening in these patients: it significantly improves dynamic balance, with effect sizes of 0.72 in the anterior direction, 1.35 posterolateral and 1.66 posteromedial on the Star Excursion Balance Test, and reduces the area of the centre of pressure ellipse in static balance by 11.62 mm² on average.18

There is no contradiction with the previous paragraph. The proprioceptive deficit is local; postural control, on the other hand, is a matter of the whole chain. Loading the ankle and strengthening the hip are not two competing options, they are two levers acting on different things.

What rehabilitation, and at what level of evidence?

This is the strong point of this file. Where many of the conditions we treat rest on fragile data, chronic ankle instability has dozens of randomised trials, several network meta-analyses, and direct comparisons between modalities. The message is not “do proprioception”: it is more precise than that.

Which modality for which deficit

The most useful synthesis for practice was published in 2026: 58 studies, 2,097 participants, with the explicit aim of determining the relative effectiveness of each modality on each deficit. Its results read like a prescribing table.16

• balance training brings benefits across the whole spectrum: patient-reported function, dynamic balance, joint position sense, concentric strength and functional performance. It is the base.
• Meanwhile strengthening improves reported function, dynamic balance and concentric strength.
• Training that is three-dimensional, training that is stroboscopic and training that is neuromuscular all improve reported function and dynamic balance; the stroboscopic kind additionally benefits joint position sense.
• Training by Vibration improves only dynamic balance.
• And a negative finding that must be quoted: no intervention significantly improved force sense or eccentric strength.

A network meta-analysis completes the picture on inversion muscle function, from nine studies and 366 participants. Every modality does better than no treatment, but the ranking is clear: the combination of neuromuscular training and strengthening comes top with a 99.9 % probability of being the best option, and an effect size of 2.82 (95 % CI: 1.89 to 3.74). Strengthening alone (SUCRA 64.6 %) is ahead of neuromuscular training alone (45.9 %), and neuromuscular training plus whole-body vibration brings up the rear (38.9 %).19

One counter-intuitive result deserves flagging. Another network meta-analysis, this time centred on joint position sense, places foot and ankle strengthening exercise first (SUCRA 74.6 %), ahead of static balance alone (67.9 %) and corrective exercise (56.1 %). Its authors conclude that the more complex the balance exercise becomes, the less marked the proprioceptive effect.20 That does not disqualify progression towards complex tasks, which serves other objectives, but it is an invitation not to abandon simple, loaded work too soon.

The more complex the balance exercise becomes, the less marked its effect on proprioception. Difficulty is not the goal.

What dose, over how many weeks

A meta-analysis of 26 randomised trials and 1,032 participants, published in 2025, has the rare merit of crossing effectiveness with the characteristics of dose. Exercise significantly improves reported function: a mean gain of 4.59 points on the CAIT (95 % CI: 4.16 to 5.03), of 7.71 points on the FAAM activities of daily living (6.36 to 9.05) and of 11.86 points on the FAAM sport (7.86 to 15.85). The subgroup analyses suggest that manual therapy delivered once or twice a week for four weeks or less optimises the CAIT, while multimodal training once or twice a week over five to eight weeksproduces the best effects on both FAAM subscales.22

That same meta-analysis applied the GRADE method to its results, and its conclusion is cautious: the level of certainty ranges from very low to moderate. That is important to say to the patient as to the referrer: the direction of the effect is solid, its exact size less so.

Manual therapy: a real effect, on a precise target

Nine randomised trials and 364 participants have been meta-analysed on joint mobilisation. The result is clear in both directions: a significant improvement in dorsiflexion range (effect size 1.02; 95 % CI: 0.41 to 1.63) and in dynamic balance (0.49; 0.06 to 0.78), but no significant improvement in patient-reported function (0.76; 95 % CI: −0.00 to 1.52).23 The practical reading is simple: mobilisation is a tool for gaining dorsiflexion, which makes sense when dorsiflexion is limited, and not a treatment for instability.

The modalities, and the level of evidence that goes with them

The ranking above is an editorial appraisal applying the GRADE principles, and not a reproduction of a published GRADE assessment, except for the dose row, where the 2025 meta-analysis did conduct a GRADE rating and concluded to a level of certainty of very low to moderate.22 The Cochrane review, for its part, noted as early as 2011 limitations of design, conduct and reporting in the ten trials it retained, with an unclear or high risk of bias for allocation, blinding of assessors and selective reporting of outcomes.21 That caution has not entirely gone away: the trials are more numerous, they are not all better.

A programme that stands up

From these data a framework can be drawn, to be adapted to the patient and to their dominant component. The durations correspond to those that emerge from the dose analyses, that is five to eight weeks of multimodal work at one to two supervised sessions a week, completed by daily work at home.22

Taping and bracing: crutch or treatment?

The question is asked with a moral charge that has no place. People readily contrast the patient “who takes charge of themselves” with the one “who leans on a brace”. The data do not support that hierarchy.

Brace against training: the direct comparison

Three trials have compared proprioceptive and neuromuscular training head-to-head with wearing a brace to reduce the recurrence rate in athletes. The pooled data show no difference between the two strategies at twelve months. The authors conclude that the available evidence, of level II, does not favour training over bracing, and recommend choosing according to patient preference and practitioner expertise.24

The overview of systematic reviews published in the British Journal of Sports Medicine points the same way and ranks the levels: there is strong evidence for bracing and moderate evidence for neuromuscular training in preventing sprain recurrence.26 The Dutch guideline, updated in 2018, likewise retains bracing as an effective option for preventing recurrence.3

There is more than an argument of effectiveness, and this is where the chapter on the three components finds its application. Bracing and adhesive taping are explicitly placed by Wenning and Schmal among the mechanical therapies, those offered to the patient whose mechanical component dominates and which training will not compensate for.6 A brace is therefore not the consolation prize of the patient who does not train: it is the treatment suited to a component that training does not reach.

What a brace does, mechanically

The meta-analysis devoted to the effect of external supports on ankle biomechanics in these patients adds a useful nuance. With a very lowlevel of evidence, external supports reduce frontal plane excursion, but do not change the inversion angle at initial contact on landing. Limiting frontal excursion could reduce the risk of sprain. In running, frontal plane kinematics are not influenced. Reductions in the sagittal plane are observed on landing and in running, with a low to very low level of certainty, and their bearing on sprain risk remains undetermined.27

In other words: the brace limits what happens during the movement, not the starting position of the foot at the moment it touches the ground. That is consistent with the idea that it does not replace motor control.

Kinesio taping: a modest and directional effect

The most recent meta-analysis brought together eight studies and 190 participants. Taping produces a small but significant improvement in the total Y-Balance Test score (effect size 0.269; 95 % CI: 0.031 to 0.508), in the posterolateral direction of the same test (0.385; 0.106 to 0.664) and in the anterior direction of the Star Excursion Balance Test (0.686; 0.083 to 1.289). By contrast, no significant difference appears in the total SEBT score, in its posteromedial and posterolateral directions, or in the hop test. Its authors conclude that it can be a simple, low-cost adjunct to complete rehabilitation, but must not replace conventional interventions.29

When does surgery become legitimate?

The position of the guidelines has been stable for ten years and comes down to one sentence. It deserves to be read carefully, because half its content concerns what must have been done beforehand.

The threshold, and what it requires

The Dutch guideline, the most cited on this point, states that surgery should be reserved for cases that do not respond to thorough and complete exercise-based treatment.3 The two adjectives are not decorative: they set the level of demand on conservative treatment, and that is where our responsibility lies. A patient referred to the surgeon after six unsupervised sessions has not had the treatment the guideline assumes.

The international consensus of ESSKA and AFAS set out precisely to identify which patients warrant surgery, which procedure to choose, and how to treat associated conditions.25 It also points out that predicting which patient will develop instability after a sprain remains difficult, which is why preventive surgery is not possible.

What surgery brings, and what it does not

The comparison between open and arthroscopic technique has been meta-analysed in 408 patients from eight comparative studies: 193 operated on open and 215 arthroscopically. The arthroscopic technique does better on the AOFAS score at six months (92.25 against 82.4) and at one year (88.6 against 80.05), on pain at six months and at one year, and on time to return to weight bearing (9.0 weeks against 14.25). By contrast, operating time, complication rate, postoperative talar tilt and anterior drawer are statistically comparable. The authors conclude that long-term trials are needed before making arthroscopy the new reference.30

The Cochrane review, on this chapter, remains the most cautious: it concludes to insufficient evidence to prefer one surgical procedure over another, while noting limitations specific to dynamic tenodesis. It does, however, provide a result directly useful to the physiotherapist: after surgical reconstruction, early functional rehabilitation is superior to six weeks of immobilisation for restoring function, with return to work two weeks earlier and return to sport three weeks earlier.21

Finally, a point that the 2026 arthroscopic series makes concrete: in patients operated on, associated intra-articular lesions are present in 54.7 % of cases, and the poor agreement between preoperative diagnosis and intraoperative findings underlines the role of arthroscopy in identifying and treating them.7 That explains why a surgical procedure that succeeded on the ligament can leave a symptomatic ankle: it did not treat the same thing.

Surgery repairs the mechanical component. It does not rehabilitate the functional component, which is still entirely there on waking.

How do you decide about return to sport?

This is the chapter where you have to accept saying what is not known. A battery of relevant tests exists, it is documented, it can be used from tomorrow. The cut-off values, on the other hand, do not exist.

What is established: which tests

A narrative review and expert opinion, conducted by French-speaking authors from the network of the French society of sports physiotherapists, set out to identify the most relevant tools for this decision. It starts from a finding: one possible cause of the high rate of recurrence and giving way is a premature return to sport, and apart from the time elapsed, there is no specific criterion to guide the clinician.28

Four functional tests emerge as the most relevant for targeting the impairments of these patients: single-leg stance on a stable surface, the modified version of the Star Excursion Balance Test, the side hop test and the figure of eight test. On the questionnaire side, the combination of the FAAM and the ALR-RSI, a return-to-sport scale after ligament reconstruction, is retained as the most relevant.

What is not established, and how to say it

The authors of that review are explicit: although these tests and questionnaires provide a solid base, objective scientific criteria with cut-off values are still lacking. They recommend adding an analysis of the context, in particular the characteristics of the sport played, such as fatigue and cognitive load, to better appreciate the risk of recurrence. They finally suggest assessing, in ecological conditions, the ability to control ankle inversion under load on a single leg.28

A survey of French-speaking doctors on actual return-to-play practice after a lateral sprain completes that picture and confirms the heterogeneity of practice in our language area.31 The absence of a validated threshold is therefore not a French shortcoming, it is the state of the question.

What do concrete clinical cases teach us?

The two reports that follow are genuine published cases, with their identifiers. The first shows what a complete programme produces on measured indicators; the second shows what gets missed when you do not look at the ankle.

How do you apply this in practice?

This chapter condenses the above into decisions. It does not replace clinical reasoning, it sets its checkpoints.

Seven decisions, in order

1. Check that it really is chronic instability. More than twelve months since the first sprain, last injury more than three months ago, at least two giving-way episodes over the last six months. Short of that, it is a sprain in recovery, and the reasoning is that of the lateral ankle sprain.1
2. Quantify before treating. CAIT and FAAM at the first session, single-leg stance and modified SEBT straight afterwards. Without an initial measurement, progress will be an impression.
3. Look for the dominant component. Anterior drawer compared with the healthy side, on an ankle that is no longer swollen, knowing that a negative test rules nothing out.17 The rehabilitation-oriented assessment proposed by the consortium provides a structured examination framework so that nothing is left out.34
4. Start with the base, not with the spectacular. Balance and strengthening combined, on the injured ankle, with volume. Complexity comes afterwards, and it does not improve proprioception any further.20
5. Go up to the hip from the second phase. The gain in dynamic balance is documented and substantial.18
6. Offer a brace without guilt to those who need one to resume an activity, explaining that it carries the highest level of evidence on recurrence and that it does not prevent progress.26
7. Reassess at eight weeks with the same tools. Without measured progress on a genuinely conducted programme, the next hypothesis is not “more proprioception”: it is a mechanical component that dominates, and a specialist opinion is warranted.3

Five common errors

When to refer on, and to whom

• To a foot and ankle orthopaedic surgeon : no measured progress after a complete, supervised eight-week programme in a patient with signs of laxity, or repeated true sprains despite treatment.25
• To imaging : mechanical pain with blocking or catching, raising the suspicion of an osteochondral lesion or impingement, present in more than half the ankles operated on.7
• To the general practitioner or the neurologist : instability with no history of trauma, or a progressive cavovarus deformity, which may reveal a hereditary neuropathy.
• Without delay : non-mechanical night pain, fever, persistent inflammatory swelling, deterioration in general condition. Those signs do not belong to this framework.

Frequently asked questions

Will my ankle go back to being “as it was”?

The question deserves an honest answer. Rehabilitation improves, in a documented way, reported function, dynamic balance and joint position sense, and reduces giving-way episodes. It restores neither eccentric strength nor force sense, on which no modality tested has shown an effect.16 And it does not tighten a stretched ligament. The realistic objective is an ankle that no longer gives way in everyday life, not a new ankle.

How long does treatment last?

The dose analyses place the optimum around five to eight weeks of multimodal work, once or twice a week, with daily work at home.22 That is not a healing time: it is the window over which the trials measure their gains. Maintaining what has been gained means keeping up some upkeep work.

Why does my ankle give way when the examination finds nothing?

Because the instability may be functional: the ligament holds, but sensorimotor control is deficient. Deficits in joint position sense in inversion are in fact the most marked of all those measured.13 And because the anterior drawer, with a sensitivity of 54 %, misses nearly one laxity in two: “the examination finds nothing” does not mean “there is nothing”.17

Should a brace be worn all the time?

No. It has its place during effort and in risky situations, and it reduces frontal excursion during landing, without correcting the position of the foot at initial contact.27 It does not remove the need for active work, and nothing suggests that it weakens the ankle: the direct comparison with training does not separate the two strategies.24

Is coloured elastic taping of any use?

Modestly, and only in certain directions. The most recent meta-analysis finds a small improvement in the total Y-Balance Test score and in two directions, with no effect on the rest. Its authors describe it as a simple, low-cost adjunct that does not replace conventional rehabilitation.29

Can you predict, at the time of the sprain, who will become unstable?

Partly. A prospective cohort followed 82 people after a first sprain. At two weeks, the inability to perform two landing tasks, a single-leg landing and a vertical jump with landing, predicted the outcome in 67.6 % of cases (sensitivity 83 %, specificity 55 %). At six months, the combination of deficits on the Star Excursion Balance Test in the posterior directions and of the FAAM activities of daily living score correctly classified 84.8 % of cases (sensitivity 75 %, specificity 91 %).38 The practical message is clear: the single-leg landing at two weeks and dynamic postural control at six months are worth testing, because they herald something.

Should you operate if the laxity is frank?

Not straight away. The position of the guidelines reserves surgery for cases that do not respond to thorough and complete exercise-based treatment.3 And even after the operation, rehabilitation is still needed: surgery treats the laxity, not the sensorimotor deficit, and early functional recovery is part of the result.21

Does chronic instability cause osteoarthritis?

The link is documented without being quantifiable for an individual. Ankle osteoarthritis concerns about 1 % of the population and is distinctive in being secondary to trauma in more than 75 % of cases, with instability among the associated mechanical factors.8 That does not make it possible to announce a quantified risk to a given patient. It does justify treating an ankle that gives way at 25 seriously. For established osteoarthritis, see talocrural osteoarthritis.

Bibliography

All the references below have been verified one by one through the NLM E-utilities API: identifier resolved, authors, journal, year and pagination checked, abstract read before citation. All 38 identifiers were found; none remained untraceable.

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A note on method. The levels of evidence in the table of modalities are an editorial appraisal applying the GRADE principles, and not a reproduction of a published GRADE assessment, with the exception of the dose results of reference 22, where a GRADE rating was indeed conducted and concludes to a level of certainty of very low to moderate. The clinical practice guidelines of the American Physical Therapy Association covering the lateral sprain and chronic instability jointly are also the most complete reference document in the field for physiotherapy.35 Article written on 15 August 2026.