Ankle sprain

What it is

In a typical sprain the foot rolls inward under load and the ligaments on the outside of the ankle are overstretched or partly torn. The tissue itself heals over about six weeks in most cases, which is why so many people conclude they are fine and stop there.

The lasting problem is neurological. Those ligaments contain the position sensors that tell the brain where the ankle is, and the peroneal muscles on the outside of the leg rely on that information to catch a roll before it happens. Damage the sensors and the reaction time lengthens - so the ankle gives way again, and each episode makes the next more likely.

What it feels like

• Immediate pain on the outside of the ankle, often with a pop or a tear sensation
• Swelling within hours, and bruising that tracks down into the foot over days
• Painful to weight bear, particularly on uneven ground
• Afterwards, an ankle that feels unreliable and gives way on kerbs, grass or in the dark
• Repeat sprains from increasingly trivial things

What causes it

Most people have more than one of these at once, and they feed each other. Read the list looking for the two or three that sound like your week rather than for the one true answer — the ones that describe you are the ones worth acting on.

The mechanism itself

The foot rolls inward while loaded - a kerb, a pothole, another player's foot, a step misjudged in the dark. The outer ligaments are the restraint and they are overwhelmed.

Loss of position sense afterwards

The damaged ligaments carry the sensors that tell the brain where the ankle is in space. Without accurate information the corrective response is late, and late is the same as absent when the roll takes a fraction of a second.

Slowed peroneal reaction time

The peroneal muscles on the outside of the lower leg are what actively resist the roll. Their reaction time is measurably slower after a sprain and does not recover on its own.

Rehab that stopped when the pain stopped

This is the crux. Pain settles in a couple of weeks and balance deficits last months. Almost nobody continues balance work past the point of comfort, which is precisely why recurrence is so common.

A previous sprain

The strongest predictor of an ankle sprain is having had one. Each episode adds ligament laxity and further degrades the sensing, so the threshold falls each time.

Reduced ankle dorsiflexion

A stiff ankle after a sprain changes how the foot lands and reduces the margin available to recover from a roll. It is very common post-sprain and rarely addressed.

Weak hips

Balance on one leg is a hip task as much as an ankle one. Weak glute medius means the whole leg is less controlled, and the ankle is left to save a situation the hip should have prevented.

Fatigue and terrain

Most recurrences happen late in an activity, on uneven ground, or in poor light - all situations where the sensing system has less to work with and the muscles are slower.

Who tends to get it

• Anyone who has sprained that ankle before, which is by far the biggest factor
• Court and field sport players - basketball, netball, football, tennis
• Runners on uneven ground or trails
• Older adults, in whom a sprain also carries a fall risk
• Anyone with generalised joint hypermobility

What makes it worse, and what settles it

The qFIT routine for this

Ready-made routineAnkle Stability & Sprain Recovery

qFIT already has this one built. It runs massage first, then stretching, then strength — the order that works on a body that is already sore — and every activity in it carries the reason it is there.

The button below opens your Checklist with this routine already selected, so instead of your whole list you land on just its Categories, Targets and Exercises, each with its checkbox, ready to tick as you work through them.

Have more than one problem? Tick yours under My Problems on My Profile and your Checklist's Routine list gains Recommended for my problems — every routine for the problems you picked, merged into one. Your picks stay private; that filter is the only thing they feed.

Get it checked if…

Cannot take four steps; bone tenderness on the back edge or tip of either ankle bone, the navicular, or the base of the fifth metatarsal (the Ottawa ankle rules) - X-ray; obvious deformity; a numb or cold foot

And whatever the body part: chest pain or unusual breathlessness on exertion; a fever alongside the pain; unexplained weight loss; pain that is constant and unrelated to how you move; new numbness, weakness or loss of bladder or bowel control; or one calf that is swollen, warm and painful. Any of those, stop and get assessed.

How it usually goes

The ligament heals in about six weeks and the balance deficit lasts far longer - often six months or more, and indefinitely if it is never trained. Balance training after a sprain roughly halves the recurrence rate in trials, which makes it the highest-value thing on this page and the most commonly skipped. Inability to weight bear at all, bony tenderness at the ankle bones or the base of the fifth toe bone, or an ankle that looks deformed needs an x-ray rather than a rehab plan.

Prevalence basis: US National Electronic Injury Surveillance System and emergency-department injury series; the most common single musculoskeletal injury in both sport and everyday life

Others the same routine covers

These share the Ankle Stability & Sprain Recovery routine, so the work is the same. If one of them also sounds like you, that is a reason to expect more from it, not less.

This is general information, not a diagnosis, and it cannot examine you. If it matches you, use it to ask better questions of a clinician rather than to replace one.