What is Sinus tarsi syndrome?
The sinus tarsi sits on the lateral (outside) aspect of the foot, just below the ankle.
It is a canal that sits between the calcaneus (heel bone) and talus bones, which houses a ligament, small blood vessels, fat and other connective tissue.
The sinus tarsi is also lined with a synovial membrane which allows for the joints to move past each other and function smoothly.
What does Sinus tarsi syndrome feel like?
Those suffering with sinus tarsi pain will present with pain on the outside (lateral) aspect of the foot.
This pain can sometimes be diffuse and hard to pinpoint the exact site of pain.
The pain may ease with exercise, however, it is often aggravated by walking or running on uneven surfaces.
If the pain has begun after an acute injury, such as an ankle sprain, mild swelling may be seen.
What causes Sinus tarsi syndrome?
There are a number of factors that can contribute to sinus tarsi syndrome including:
A pes planus foot type (flat feet)
A flat foot position causes compression of the sinus tarsi and bone on bone pressure between the calcaneus and talus bones.
Both inversion or eversion ankle sprains can cause injury to the sinus tarsi.
Inversion (lateral) ankle sprains open up the sinus tarsi and can damage the connective tissue that lies within this area.
Eversion (medial) ankle sprains can occur in sports such as soccer or high jump, where the foot and ankle are placed into a more pronated position like it is in those with flat feet. This position can compress the sinus tarsi.
Inflammation of the synovial fluid within the sinus tarsi can cause pain. This can occur both after an acute injury or after chronic overuse or pressure in the area.
Chronic inflammatory conditions
How is Sinus tarsi syndrome diagnosed?
Sinus tarsi syndrome can often be diagnosed through simple palpation and movement of the nearby joints, as well as thorough history taking. This helps to identify any recent injuries that may have contributed to the pain.
We also conduct a thorough examination of the feet including testing the range of motion and strength of the feet, as well as standing and walking/running assessments.
These assessments will allow us to suspect a sinus tarsi injury.
Often, we will send off for scans (X-ray, ultrasound, MRI) to identify the extent of the injury which will help guide treatment.
How is Sinus tarsi syndrome treated?
Treatment of sinus tarsi syndrome can include:
NSAIDs (non-steroidal anti-inflammatory medications)
These can help to alleviate or manage your pain. Consult with your doctor to determine if these are suitable for you.
This will assist with reducing inflammation in the area, as well as providing a slight analgesic effect which involves a reduction in pain.
Various taping methods can be used to support both the ankle joint and the sinus tarsi region.
Taping is aimed at offloading the affected area in the short term and if effective, can highlight the need for other treatments including orthotics.
Orthotics can assist with realigning the joints within the feet to reduce pressure and allow them to function effectively.
This treatment option is best suited to those with flat feet or high arches, as well as those who suffer from repeated ankle sprains.
Balance and strength training
This is particularly important for those who have sustained an acute injury to the sinus tarsi, such as an ankle sprain. This will involve a tailored program to focus on any weaknesses.
Exercises may include theraband exercises, calf raises, balance exercises and sport specific exercises including change of direction or high impact movements.
Cortisone injections will assist with reducing pain, however are recommended as an adjunct to other treatments to address the cause of the sinus tarsi pain.
What to do if you think you could have Sinus tarsi syndrome
If you’re experiencing pain or discomfort in your lower limbs and/or feet, or if anything we’ve talked about today sounds familiar to you, come see us at Watsonia Podiatry. If you’re suffering from Sinus tarsi syndrome, we can help treat you today.
Book in to see us by calling us on 03 9432 2689 or online here.