What is sinus tarsi syndrome?

The sinus tarsi is a small channel on the outer side of the hindfoot between the talus and calcaneus bones. Pain in this area is often called sinus tarsi syndrome.

People commonly notice tenderness just in front of the outer ankle bone. Walking on uneven ground, changing direction or loading one leg may also reproduce the pain.

Sinus tarsi pain often develops after an ankle sprain. However, the term does not always identify one single injured structure. Subtalar joint irritation, ligament injury, instability and other nearby ankle problems can produce a similar pain pattern.

For a broader overview of ankle conditions, see our ankle pain guide.

What does sinus tarsi syndrome feel like?

The symptoms vary depending on the underlying cause and how long the problem has been present.

• Local tenderness at the outer-front part of the ankle or hindfoot.
• A dull ache after walking, running or prolonged standing.
• Pain when walking on uneven ground, trails or side slopes.
• Discomfort with twisting, pivoting or changing direction.
• A feeling that the ankle or hindfoot is less steady or confident.
• Occasional swelling or a feeling of fullness around the area.

Some people have symptoms mainly during sport. Others notice discomfort during ordinary walking, particularly after a previous ankle sprain.

Why does sinus tarsi pain happen?

Several factors may irritate structures around the sinus tarsi or increase the load through the subtalar joint.

Previous ankle sprain

An ankle sprain can leave stiffness, swelling, ligament irritation or reduced balance and control. Repeated ankle sprains can also contribute to ongoing instability.

Chronic ankle instability

Some ankles continue to feel as though they may roll or give way after the original injury has healed. This pattern may be associated with chronic ankle instability and increased stress around the subtalar joint.

Repeated loading

Trail running, hills, court sports and activities involving frequent turning can place repeated demands on the ankle and hindfoot. A sudden increase in training may also contribute.

Foot and hindfoot mechanics

Foot posture and movement can influence how load passes through the hindfoot. Some people with increased pronation or a flatter foot posture may benefit from footwear advice or an assessment of whether orthotics are appropriate.

Nearby ankle problems

Pain around the sinus tarsi can occur alongside other conditions. For example, peroneal tendinopathy may change how the outer ankle is loaded.

What else can feel like sinus tarsi syndrome?

Pain on the outer side of the ankle does not always come from the sinus tarsi itself. Several conditions can overlap or produce similar symptoms.

A careful assessment helps determine whether sinus tarsi pain is the main problem, part of ongoing ankle instability or one feature of another ankle condition.

How is sinus tarsi syndrome assessed?

Your physiotherapist will usually look at how the symptoms started, what activities reproduce them and how well your ankle and foot control load.

Can sinus tarsi syndrome show on MRI?

An MRI can sometimes show changes around the sinus tarsi, ligaments or subtalar joint. However, imaging findings do not always explain a person’s pain by themselves.

Many presentations can first be assessed clinically. Imaging may become more useful when symptoms persist, repeatedly return, follow significant trauma or fail to improve as expected.

Your physiotherapist, GP or specialist can advise whether imaging is likely to change your management.

How is sinus tarsi syndrome treated?

Treatment depends on what is causing the pain. Rehabilitation often aims to calm the irritated area while rebuilding the strength, balance and control needed for everyday activity or sport.

1. Adjust aggravating load

   Temporarily reducing hills, uneven surfaces, repeated turning or excessive training volume may help settle symptoms without stopping all activity.

2. Rebuild ankle strength and control

   Rehabilitation may include calf and lower-leg strengthening, foot control exercises and balance work. These exercises are particularly useful when symptoms developed after an ankle sprain.

3. Improve balance and proprioception

   Single-leg balance and progressively more challenging movement tasks can help restore confidence and control after ankle injury.

4. Review footwear and support where needed

   Your physiotherapist may discuss footwear, taping, bracing or orthotics when these options address a relevant contributing factor.

5. Build back to work, running or sport

   Progression may move from comfortable walking to single-leg loading, hopping, landing, direction changes and activity-specific drills.

If your symptoms began after an ankle sprain, our sprained ankle guide and ankle sprain prevention advice provide further information.

People returning to running or sport may also benefit from a staged approach to strength, landing and change-of-direction work. Read more about sports injury physiotherapy.

When are injections or specialist review considered?

Some people continue to have significant sinus tarsi pain despite a well-structured rehabilitation program. In these situations, further imaging or medical review may help clarify the diagnosis.

A doctor or specialist may sometimes discuss an injection as part of management. Any potential short-term benefit needs to be considered alongside the underlying cause of the pain and the possibility that symptoms may return.

Persistent instability, recurrent giving way or symptoms that do not respond as expected may also warrant further assessment.

How long does sinus tarsi syndrome take to improve?

There is no single recovery timeframe. Progress depends on the underlying cause, how long symptoms have been present, previous ankle injuries and whether instability continues.

Some people improve over several weeks with appropriate load management and rehabilitation. Longer-standing or recurrent problems may take several months and need a more gradual return to running or sport.

Rather than relying on a fixed date, progression is usually based on symptoms, walking tolerance, strength, balance and the demands of the activity you want to return to.

When should you have sinus tarsi pain assessed?

Consider an assessment if pain around the outer ankle:

• continues after an ankle sprain;
• keeps returning when you walk, run or play sport;
• makes uneven ground difficult;
• is associated with repeated ankle giving way;
• limits work, exercise or normal daily activity; or
• is not improving with sensible changes to activity.

Related ankle information

What to do next

If pain around the outer ankle is lingering after a sprain, keeps returning or makes uneven ground difficult, an assessment can help clarify what is driving the problem.

Your physiotherapist can assess ankle and subtalar movement, strength, balance and contributing factors, then develop a rehabilitation plan based on your symptoms and goals.

Frequently asked questions about sinus tarsi syndrome

References

1. Willegger M, Bouchard M, Veljkovic A, et al. The evolution of sinus tarsi syndrome—what is the underlying pathology?—a critical review. J Clin Med. 2023;12(21):6878.
2. Arshad Z, Lau Y, Rahman S, et al. Current concepts in sinus tarsi syndrome: a scoping review. Foot Ankle Surg. 2021;27(7):739-747.
3. Pereira BS, Hamid KS, Soni A, et al. Current concepts in subtalar instability. Foot Ankle Orthop. 2021;6(3).
4. Xu X, et al. Clinical observation of sinus tarsi syndrome after lateral ankle sprain. 2024.