Sinus Tarsi Syndrome
The Highlights
Sinus Tarsi Syndrome involves excess repetitive compression or a sudden strain to the open in the front-outer space of the rearfoot in a joint called the subtalar joint.
In our clinic, we can diagnose this problem easily with physical examination and occasionally with the added use of diagnostic ultrasound.
Treatment involves decompressing the joint with supportive footwear, foot orthoses (specialist insoles), taping and reducing excessive pain with steroid injections.
What is it and what are the symptoms?
The Sinus Tarsi is effective a large gap on the anterior-lateral (front-outside) part of your subtalar joint - the gap between your talus and calcaneus (heel bone). Sinus Tarsi Syndrome, put simply, is pain in this gap.
It is common in adult patients off all ages and activity levels although we tend to see it at two ends of the spectrum - young athletic individuals and older patient who have a combination of other progressive foot issues like Adult Acquired Flat Foot Deformity (AAFFD).
As mentioned, the location of the pain is typically the anterior-lateral (front-outside) part of your subtalar joint - feel for the dip around this location in front of the outer part of your ankle bone - rotating your foot around may help you feel this gap opening and closing. The pain tends to be specific to this location for Sinus Tarsi syndrome BUT as we'll talk more about, it isn't always a condition in isolation so be aware pains elsewhere may still be relevant. It may be a dull aching pain for much of the day (or may be fine for low-grade activity) but during higher activity (running, big walks, jumping etc.) can feel like quite a sharp/stabbing pain. It will tend to worsen as the day goes on but ease reliably with rest.
Why does it happen?
This gap we're calling the Sinus Tarsi is heavily populated with nerves and blood vessels which lends itself to being a sensitive spot of our foot's anatomy. Combine this with high compression forces as your foot pronates (rolls inward) and we have the ability to set off symptoms (as a side note - the amount of visual movement we see as your foot pronates is not the issue as many people still think - it's about the internal forces on the joint - we can't see this with the naked eye by tests in clinic can help us take a reasonable guess).
In our more athletic patients we can see this condition in isolation but in older individuals it's far more likely it's co-existing with other issues to do with how the rearfoot copes with the loads placed on it. We have links to some of these conditions we've spoken about already including: tibialis posterior tendon dysfunction, plantar fasciopathy and AAFFD.
What are the treatment options?
After assessing your foot, ankle and lower limb biomechanics, our Podiatrists are likely to have a good idea of what predisposing factors are placing painful amounts of load on your sinus tarsi and how to address this. Footwear is important here and sturdy walking shoes or, better yet, boots are a great place to start.
Foot orthoses (specialist insoles) selected carefully by our team can be extremely helpful in "decompressing" the sinus tarsi and will often give long-term relief, potentially combined with taping in the short term for an added boost in effectiveness. This will virtually always be given alongside an exercise programme to encourage the muscles that protect the joint to work at their fullest potential.
We will also often advocate the use of corticosteroid injections for this issue if symptoms are especially painful or not improving enough with other measures. These are very straightforward procedure performed in clinic in a matter of minutes which can massively facilitate long-term improvement when used in conjunction with the other treatments mentioned.
If there are particularly high levels of swelling and pain that don't signicantly reduce with rest, we will tend to offer diagnostic ultrasound to visualise the sinus tarsi, the rest of the subtalar joint and adjacent structures because this is a joint we often see large joint effusions and synovitis (swelling and inflammation) which could indicate an inflammatory joint disorder. If this is suspected, we will liaise with your GP to arrange appropriate further tests.
