Where and what is the sinus tarsi:
The word “sinus” refers to a cavity, most often in bone. The cavity known as the sinus tarsi is located on the outside of the foot in front of and below the outside anklebone. The cavity is formed at the junction between the heel bone and the bone that sits over the heel bone called the Talus. The heel bone forms the floor of the cavity and the talus creates the roof.
Within the cavity there are blood vessels, nerves and ligaments. The ligaments function to hold the two bones together.
“Sinus Tarsi Syndrome” refers to a painful condition located in this cavity in the rear portion of the foot. The pain is made worse with weight bearing. The pain can become much more intense when walking, running or hiking on uneven surfaces.
Causes of Sinus Tarsi Syndrome:
The most common cause of sinus tarsi syndrome is an inversion injury to the foot. This occurs when the foot rolls inward and stretches the soft tissue in the cavity. When the foot is stressed by this inward motion a tear or strain occurs to the ligaments. The injury to these ligaments results in inflammation, swelling and thickening.
The other causes of this condition are structural as apposed to the injury noted above. One of these structural abnormalities that can occur is growths or masses of soft tissue. Over growth of nerve or fat tissues in the cavity can cause increased pressure and result in pain. The pain in this area can also be caused by deviations in the bone structure. For example, bone spurs; arthritis and bone bridges can be responsible for the development of sinus tarsi syndrome.
Diagnosing Sinus Tarsi Syndrome:
To make the diagnosis of this condition the podiatrist will listen to the history of how the symptoms began and then examine the area. Most of the time, that is all that is needed to confirm sinus tarsi syndrome. In addition to the history and physical exam an x-ray should be taken to rule out bone cyst, fractures, bone bridging and arthritis. In some cases if the condition does not resolve with conservative treatment an MRI or diagnostic ultrasound may be ordered to evaluate the soft tissues in the cavity.
Another helpful procedure to determine the exact location of the pain is to inject the sinus tarsi with a small amount of local anesthesia. If upon examination after the injection the pain is gone the diagnosis is confirmed. If however, the pain is still present following the injection the injury may be in another location in the foot.
Research has shown that a majority of the people with sinus tarsi syndrome will respond favorably to conservative management. Rest, ice and compression are suggested to reduce the inflammation. Oral anti-inflammatory medications can be prescribed to further decrease the pain and swelling.
Another treatment option is to tape the foot to attempt to limit the motion at the subtalar joint. If the taping successfully reduces the pain long term treatment with a custom orthotic can be used to control the motion of the rear foot. In most cases foot orthotics are sufficient to treat this condition, however in some cases an ankle foot orthotic may be necessary to fully control the motion.
Finally, a steroid injection into the sinus tarsi may be effective at relieving the pain.
In conservative measures have not helped to relieve the pain surgery may be needed. A common surgical procedure to threat this condition is decompression or removing the abnormal tissues from the cavity. If the MRI scans shows a soft tissue mass present in the sinus tarsi surgical removal of the mass will be needed.
After the surgery, protected weight bearing in a post-operative shoe or walking boot will be required for a period of approximately 2-4 weeks.
If this surgery fails or the patient has severe arthritis the bone in the rear foot may need to be fused.
What is Sinus Tarsi? – 3 Points to Know About Sinus Tarsi
Learning on what is Sinus Tarsi. It is a small osseous canal which goes up to the ankle below the talus bone. It is the space surrounded between the talus and calcaneum. It is continuous medially with a thin tarsal canal. It comprises of a cervical tendon and the three roots of the inferior extensor retinaculum.
What is Sinus Tarsi and what does it constitute of? The sinusitis and the canal are full of blood vessels, which provide the necessary nutrition to the talus.
The pain is more sever in the hind foot and an injection in the sinus tarsi would give a relief from pain. The pain is due to vascular engorgement or it may be termed a nerve aggravation because of fibrosis. An ankle pain is inevitable; the ankle becomes inflamed because of the synovial fluid which is present in the sinus tarsi getting swollen.
What is sinuses tarsi syndrome
- You can feel the pain in the front and lateral part of the ankle.
- The opening to the sinusitis tarsi becomes soft.
- Unbearable pain is noticed on the ankle which is affected and usage of that ankle for any exercise causes ache.
One could come back to normal, if an injection is given to relieve pain. The case could be confirmed by a MRI scan which shows too much of fluid in sinus tarsi.
Dealing with what is sinus tarsi
Patients are requested to take adequate rest from painful work. Immediate relief could be sought by applying a cold pack of ice on the affected area. NSAID or a non steroidal anti inflammatory drugs could be used for prompt relief. Patients are requested to avoid discourse if they are taking treatment for asthma. Electrotherapy also reduces redness. Subtalar joint movements are essential for quick recovery from the pain. Biomechanical problems should be corrected like rotary motion. Exercises are necessary to bring back the required strength to the affected region. Wobble board is one such exercise.