Tarsal Tunnel Syndrome

You have a nerve called the posterior tibial nerve that runs down the inside of your leg and crosses the inside of your ankle, where it branches off to innervate (give feeling to) different areas of your foot. As it crosses the inside of the ankle, it passes through a naturally-occurring space or ‘tunnel’ between the bones called the tarsal tunnel.

When the space inside the tarsal tunnel is reduced, which can be the result of various injuries, diseases or biomechanical factors related to the structure and function of your foot or ankle, the nerve can become compressed or pinched. It is this compression that produces symptoms that can affect the entire foot and even the lower leg, though they tend to be more prominent on the bottom of the foot and the inside of the ankle.

The symptoms of tarsal tunnel syndrome are classed as ‘neural’, and typically include burning, numbness tingling at the foot and ankle which may be accompanied by shooting pain (which some people describe as electric shocks) or discomfort. Some people may notice their symptoms start very suddenly, while others notice a gradual progression, which is likely associated with the cause of your tarsal tunnel syndrome in your unique case.

The compression or pressure on the posterior tibial nerve can be caused by anything that reduces the space available within the tarsal tunnel. This means that the causes can vary greatly, but may include:

• Injuries, sporting or otherwise, that cause swelling around the ankle. In sports, it is the high amounts of pressure on the structures of the foot and ankle that contribute to damage and swelling
• Cysts within the tarsal tunnel or surrounding areas
• Bone spurs or swollen tendons in the area
• A flat foot posture due to the outwards tilting of the bones that can strain or compress the nerve
• Medical conditions like arthritis or diabetes which can cause inflammation at the ankle joints
• Varicose veins that develop around the nerve

Interestingly, research shows that up to 43% of patients with tarsal tunnel syndrome have a history of trauma including events such as ankle sprains. Abnormal foot biomechanics also contributes to disease progression, as does having hypothyroidism, gout, hyperlipidemia, certain metabolic diseases, and diabetes.

As the key to treating tarsal tunnel syndrome is identifying and managing the cause, having an appointment with your podiatrist for a biomechanical assessment is highly recommended and should be completed as early as possible. 

To help reduce your inner ankle pain until you are able get in to see your podiatrist, you can try:

• Icing your inner ankle (through a towel or cloth to protect the skin) for no more than 15 minutes at a time, four times per day. This may help reduce your pain and inflammation, if the cause of your tarsal tunnel syndrome is related to swelling in the area. You can also keep your ankle elevated to help promote swelling reduction.
• Using non-steroidal anti-inflammatories (NSAIDs) as needed to help relieve pain and swelling, or if no swelling is present, using paracetamol or acetaminophen as directed.
• Switching to good, supportive footwear - such as good joggers with a strong heel counter that holds your ankle in place well, and limits unwanted excess ankle movement that may further narrow the space in the tarsal tunnel and worsen your symptoms. In this case, any light or barefoot sneakers are not suitable as they generally do not offer the required level of support. 
• Avoiding physical activity that aggravates and worsens your symptoms

Here at Matt Raden Podiatry, our trusted and experienced podiatrists listen to the concerns, goals and needs of our patients with foot and ankle pain, and utilise a range of evidence-based treatment methods to help you get the best outcome.

Every appointment starts with a comprehensive assessment to understand the biomechanics of your ankles, feet and legs, and all of the factors that are playing a role in compressing the posterior tibial nerve within your tarsal tunnel, or narrowing the space available within the tunnel. As each case can greatly vary, it’s a good idea to take notes of exactly which movements and positions produce or exacerbate your symptoms, as this will give valuable information to your podiatrist to use in their assessment.

We’ll then create a tailored treatment plan based on your results that focuses on helping open up the joint space and treat any issues that are causing swelling within or near the tarsal tunnel. To achieve this, we may use:

• Orthotics (insoles): using custom-prescribed foot orthotics that sit inside your shoe can help effectively manage tarsal tunnel syndrome that is caused by having a foot posture that narrows the joint space at the tarsal tunnel, arthritic changes to the ankle, and various other biomechanical causes.
• Footwear assessment and recommendations: wearing unsupportive shoes that let your ankles roll freely can work against the recovery progress you are making by allowing further stress on the structures within the tarsal tunnel. We will assess the footwear you currently wear on a daily basis (please bring these to your appointment) and will make recommendations as needed. This may include temporarily wearing your supportive shoes inside your home.
• Stretching and strengthening program: stretching and strengthening exercises can be beneficial in helping address any muscle imbalances that may be contributing to your symptoms, which is great for helping prevent recurrence of tarsal tunnel syndrome in the future.
• Bracing - in some cases, bracing may be beneficial in limiting movements that may otherwise compress the nerve and aggravate your symptoms

If your unique circumstances mean that we are not seeing the typical results we’d expect with treatment, we may refer you for additional care such as cortisone injections to help you manage your symptoms, or for medical imaging to assess for the presence of a cyst in or near the tarsal tunnel. Based on the results, a referral to a specialist like an orthopaedic surgeon may be warranted.