Why Does My Ankle Keep Giving Way After a Sprain?

That first ankle sprain was months ago. Maybe longer. You did the RICE thing, wore a brace for a while, and figured it healed up fine. Then it happened again. And again. Now your ankle rolls on uneven sidewalks, gives out during a simple change of direction, or just feels wobbly walking down stairs — like it can't be trusted anymore.

That feeling isn't in your head. It has a name: chronic ankle instability. And it's a lot more common than most people realize, especially in anyone who's sprained an ankle once and never fully rehabbed it.

Chronic ankle instability happens when ligament damage from a previous sprain, combined with lost balance and muscle control, leaves the ankle unable to stabilize itself during normal movement. It's not just "a weak ankle" — it's a measurable deficit in proprioception and strength that specific rehabilitation can address. Most people see meaningful stability improvement within 3-4 weeks of targeted treatment.

Here's what's actually going on, why it doesn't resolve on its own, and what actually fixes it.

Why Does My Ankle Keep Giving Way After a Sprain?:

What Happens to an Ankle After a Sprain That Doesn't Fully Heal?

When you sprain your ankle, you stretch or tear the ligaments — usually the ones on the outside (lateral ligaments). Those ligaments do more than hold bones together. They're loaded with nerve receptors that tell your brain exactly where your ankle is in space at any given moment.

Injure those ligaments, and you don't just lose structural support. You lose some of that sensory feedback too. Researchers call this proprioceptive deficit, and it's one of the core problems behind chronic ankle instability.[^1]

So even after the ligament itself "heals" — even after swelling goes down and pain fades — the connection between your ankle and your brain can still be compromised. Your ankle doesn't communicate its position as clearly. Your muscles don't react as quickly to catch a roll before it happens. And that's the setup for repeat sprains.

Why One Bad Sprain Turns Into a Chronic Problem

Not everyone who sprains an ankle develops lasting instability. Plenty of people sprain an ankle, rehab it properly, and never think about it again. So what separates a one-time injury from an ankle that keeps giving way?

Research points to a few consistent factors:

Incomplete Rehabilitation

The single biggest factor is simply not finishing the job. Most people stop treatment once pain and swelling resolve — often within 2-3 weeks. But proprioception and neuromuscular control take longer to restore than pain relief does. Stopping early leaves the underlying instability untreated.

Repeated Sprains Compounding the Damage

Each subsequent sprain adds more ligament laxity and further degrades proprioceptive function. It becomes a cycle: instability leads to another sprain, which leads to more instability.

Altered Movement Patterns

After an ankle sprain, people often unconsciously change how they walk, run, or cut to protect the ankle. These compensations can persist long after the ligament has healed, and they contribute to ongoing dysfunction.

Weak Peroneal Muscles

The peroneal muscles on the outside of the lower leg are your ankle's primary dynamic stabilizers — they react quickly to prevent excessive rolling. Research on functional ankle instability found measurable deficits in peroneal muscle response time and strength in people with chronic instability compared to those without.[^2]

What the Research Actually Shows About Fixing This

This isn't a mystery injury with unclear treatment. Chronic ankle instability has been studied extensively, and the research is fairly consistent on what works.

A scoping review analyzing a decade of chronic ankle instability research — covering hundreds of studies — found that balance and proprioceptive training programs are the most well-supported intervention for improving both stability and self-reported ankle function.[^3]

More specifically, a review of randomized controlled trials examining balance and proprioceptive training found consistent improvement across standard outcome measures used to assess ankle instability, including balance testing and functional ability scores.[^4]

There's also emerging evidence on the neurological side. Studies have identified altered brain activity patterns in people with chronic ankle instability — specifically, reduced ability of certain motor cortex regions to recruit the muscles that stabilize the ankle.[^5] That's a fairly compelling explanation for why "just building strength" without addressing balance and coordination often falls short. The problem isn't purely muscular. Part of it is neurological retraining.

How We Figure Out What's Actually Going On With Your Ankle

Not every unstable ankle is unstable for the same reason, which is why assessment matters before treatment starts.

We look at ligament integrity first — is there actual mechanical laxity, or is the instability more functional (meaning the ligaments have healed reasonably well, but the neuromuscular control hasn't caught up)? This distinction changes the treatment approach.

We test balance on the affected leg versus the unaffected leg, usually with something like a modified Star Excursion Balance Test, which gives us an objective measure of how far off things really are.

We check strength and reaction speed in the peroneal muscles specifically, since that's often where the biggest deficits show up.

We also watch how you actually move — walking, cutting, stepping off a curb — because compensations show up in movement long before someone can describe them.

What Treatment Actually Looks Like

Once we know what's driving your specific instability, treatment is built around it. Generally, that includes:

Balance and proprioceptive training. This is the foundation, and it's not just standing on a wobble board mindlessly. Progressive balance work — starting stable and controlled, advancing to unstable surfaces and dynamic movement — retrains the ankle's ability to sense and correct its position in real time.

Peroneal strengthening. Building strength and, just as important, speed of activation in the muscles that catch an ankle roll before it becomes a sprain.

Neuromuscular retraining for sport or activity-specific movement. If your instability shows up during running, cutting, or hiking, treatment eventually needs to look like those activities — not just seated exercises.

Gradual return to full activity. Loading the ankle progressively as stability and confidence return, rather than jumping back into high-risk movement too soon.

Many patients notice real improvement in balance and confidence within just 1-2 visits, especially once they understand what specific exercises are addressing. Most people see meaningful stability gains within 3-4 weeks of consistent work, and full return to sport or high-demand activity typically takes 6-8 weeks depending on how long the instability has been present.

Do You Actually Need Treatment, or Will This Just Go Away?

If your ankle has given way more than once, or if you notice it feeling unreliable on uneven ground, it's worth getting assessed. Chronic ankle instability doesn't typically resolve without addressing the underlying proprioceptive and strength deficits — that's part of why it's called "chronic."

Worth scheduling an evaluation if: your ankle has rolled or given way more than once since the original sprain, you avoid certain activities because you don't trust your ankle, you feel unstable on stairs or uneven surfaces, or it's just been a while since that first sprain and things never quite felt normal again.

Common Questions About Chronic Ankle Instability

Is this the same thing as just having a "weak ankle"?

Not exactly. It's a specific, measurable combination of mechanical laxity and impaired neuromuscular control. "Weak ankle" undersells what's actually happening and what needs to be treated.

Can this get better years after the original sprain?

Yes. People often assume too much time has passed, but proprioceptive and strength deficits respond to targeted training regardless of how long they've been present.

Do I need an MRI or imaging first?

Usually not. Most chronic ankle instability is diagnosed through clinical assessment — testing, movement observation, and history. Imaging becomes relevant if there's suspicion of more significant structural damage.

Will a brace fix this permanently?

A brace can help temporarily, especially during high-risk activity, but it doesn't retrain the underlying neuromuscular deficits. Long-term reliance on bracing without rehab tends to keep the instability rather than resolve it.

How many times can an ankle sprain before it becomes "chronic"?

There's no magic number, but if you've had multiple sprains on the same ankle, or ongoing instability lasting more than a few months after the last one, that pattern qualifies.

Can I keep running or playing sports while treating this?

Often yes, in modified form. We typically adjust intensity or activity type early in treatment and progress back to full participation as stability improves.

What if both ankles are unstable?

That happens more than people expect, particularly in athletes with a history of multiple sprains. Both sides get assessed and treated, though they don't always need identical programs.

Is surgery ever necessary?

For most people, no. Surgery is generally reserved for cases with significant mechanical ligament laxity that hasn't responded to a thorough course of rehabilitation.

Why Does My Ankle Keep Giving Way After a Sprain?: Bottom Line

An ankle that keeps giving way isn't something you just have to live with, and it's not purely a strength problem you can fix by yourself with random exercises off the internet. It's a specific deficit in balance, proprioception, and muscle response time — and it responds well to targeted rehabilitation.

Most people notice improved confidence and stability within the first couple of visits, meaningful gains within 3-4 weeks, and full return to activity within 6-8 weeks.

If your ankle keeps rolling or feeling unreliable, let's find out why.

Schedule a Physical Therapy Evaluation at Nashville Physical Therapy & Performance. You'll get completely 1:1 care with your therapist for the entire visit — no aides, no rotating techs. We'll assess exactly what's driving your ankle instability and build a plan to get it back to trustworthy. Available at South Nashville, East Nashville, and The Nations/West Nashville. Call 615-428-9213 or book online at nashvillept.com.

References

[^1]: Santos MJ, Liu W. Possible factors related to functional ankle instability. Journal of Orthopaedic & Sports Physical Therapy. 2008;38(3):150-157.

[^2]: Santos MJ, Liu W. Possible factors related to functional ankle instability. Journal of Orthopaedic & Sports Physical Therapy. 2008;38(3):150-157.

[^3]: Scoping review of chronic ankle instability research demographics and outcomes. Journal of Science and Medicine in Sport. 2025.

[^4]: Rebuilding stability: exploring rehabilitation methods for chronic ankle instability. Sports (Basel). 2024;12(10):282.

[^5]: Kosik KB, et al. An updated model of chronic ankle instability. Journal of Athletic Training. 2019.