High Ankle Sprain (Syndesmosis): Why It Heals Slower Than a Normal Ankle Sprain

Most ankle sprains are the classic rolled ankle, and they settle in a few weeks. A high ankle sprain looks similar at first but behaves completely differently, and it can drag on for months if it is treated like an ordinary sprain. Knowing which one you have changes the timeline and the plan.

Two different injuries that look alike

When people say "ankle sprain," they almost always mean the common lateral ankle sprain. That is the rolled ankle: the foot turns inward, and the ligaments on the outer side of the ankle, below the ankle bone, get overstretched. These ligaments sit in a spot that does not take huge load, and most of these sprains settle over a few weeks with movement and balance work.

A high ankle sprain is a different problem in a different place. It injures the syndesmosis, which is the set of ligaments that hold the two lower leg bones, the tibia and fibula, tightly together just above the ankle joint. This binding keeps the ankle joint stable and correctly spaced. High ankle sprains usually happen with a twisting or outward force on a planted foot, which is why they are common in contact sports and in sports with hard cutting and pivoting.

The reason this matters is that the two injuries share the early picture, pain and swelling around the ankle, but they need different handling. Treating a high ankle sprain as if it were a simple rolled ankle is one of the more common ways a treatable injury turns into a long-running problem.

Why the syndesmosis heals slower

The core reason a high ankle sprain heals slower comes down to load. The syndesmosis is under high force every time you push off, run, or change direction. So even normal walking and daily movement keep stressing the healing tissue, which slows the repair. A lateral ankle sprain does not sit under the same constant pulling and spreading load, so it usually settles faster.

The numbers back this up. The Hospital for Special Surgery reports that high ankle sprains take nearly twice as long to heal as common ankle sprains, and that some people return to sport within about six weeks while about half have some symptoms for as long as six months. That is a wide range, and it depends on severity, but it makes the point: this is a slower injury by nature, not because you did something wrong.

There is a second reason to respect it. If the joint between the two leg bones is left even slightly unstable and you load it hard too soon, the space between the bones can widen, and that stresses the cartilage inside the ankle. Over time that is what leads to lasting problems. This is why protecting the injury early and healing it fully is not being overly cautious. It is the whole point.

How to tell them apart

You cannot always tell a high ankle sprain from a normal one by how it felt at the time, but there are useful clues. A lateral ankle sprain hurts and swells over the outer ankle bone. A high ankle sprain tends to hurt higher up, above the ankle joint, in the area between the two lower leg bones. It often hurts more with pushing off, going up on the toes, or twisting than a simple roll does.

Because the two are handled so differently, and because a missed high ankle sprain can cause lasting trouble, this is a case where an assessment earns its place. A physiotherapist can use specific tests to load the syndesmosis and see how it responds, and imaging is sometimes needed to check whether the joint between the bones is stable or has widened. If you want the wider picture of how we assess and rebuild any ankle sprain, our post on ankle sprain rehab and balance retraining covers the common lateral sprain in detail.

Early management

Early on, a high ankle sprain usually needs more protection than a rolled ankle. That often means a period of limited or protected weight-bearing, and sometimes a brace or a walking boot, to take load off the healing syndesmosis while it starts to repair. This is the opposite of the very early movement we often encourage for a mild lateral sprain, which is exactly why the two injuries should not be managed the same way.

Once the tissue has had a chance to settle, the plan moves through restoring range of motion, then strength, then balance and control, and finally the sport-specific loading that pushing off and cutting demand. The pace is guided by how the syndesmosis tolerates load, not by a fixed schedule. Some ache with rehabilitation is expected, but pain that climbs with loading is a sign the dose ran ahead of the healing, and we pull it back.

Return-to-sport criteria that matter

The biggest mistake with a high ankle sprain is returning to sport by the calendar. "It has been six weeks" is not a reason to play. The syndesmosis has to have healed enough to take hard load, or the joint keeps getting irritated and the injury drags on.

Before returning to sport, the ankle should have full range of motion, full strength, and good balance and control, and it should tolerate the specific demands of the sport. For many people an ankle brace during the early return phase is sensible. These are functional checkpoints, not dates on a calendar, and they exist to protect the joint from the widening and cartilage stress that early hard loading can cause. Our post on criteria-based return to sport explains why we test readiness against what the athlete can actually do rather than how much time has passed.

When surgery is considered

Most stable high ankle sprains are managed without surgery. Surgery comes into the picture when the joint between the two leg bones is unstable or has widened, because that instability is what damages the cartilage and leads to long-term problems if it is not corrected. Deciding whether an injury is stable is not something you can judge from how much it hurts. It needs a proper assessment and often imaging, which is another reason a high ankle sprain deserves more than a wait-and-see approach.

When to get it assessed

If you have an ankle injury that hurts higher up than a normal rolled ankle, that hates pushing off or twisting, or that simply is not settling on the timeline you would expect from a rolled ankle, get it assessed. High ankle sprains are missed often, and catching one early changes how it is protected and how well it recovers. It is worth being seen promptly if you cannot bear weight, if the ankle is very swollen or deformed, or if the pain is severe, since those features can point to a fracture and may need imaging first.

Book a 30-minute appointment and we will assess your ankle, work out whether the syndesmosis is involved, and build a protection and rehabilitation plan with return-to-sport checkpoints matched to how the joint is actually healing.

This article is general information about ankle injuries. It is not personal medical advice. A regulated practitioner can confirm whether the patterns described apply to you.

Sources

• High Ankle Sprain (Syndesmotic Ankle Sprain) - Hospital for Special Surgery
• Syndesmotic Ankle Sprains - Physiopedia
• College of Physical Therapists of BC (CPTBC)

This article is for general information only and does not constitute medical advice, diagnosis, or treatment. Individual presentations vary — assessment findings and treatment plans differ from person to person. If you are experiencing severe symptoms, neurological changes (numbness, weakness, bowel or bladder changes), or a significant trauma, contact your physician or emergency services. Care at Medstar Sport Physio & Health is provided by practitioners registered with their respective British Columbia regulatory colleges.