What is Tibial Neuropathy?
Tibial neuropathy refers to any issues with the tibial nerve, which often relates to tarsal tunnel syndrome. This syndrome involves the tibial nerve as it crosses through the tarsal tunnel located near the ankle. While both tibial neuropathy and tarsal tunnel syndrome involve the same nerve, they are different conditions.
The tibial nerve comes from the sciatic nerve, starting around the area of the popliteal fossa, which is a shallow depression located at the back of your knee joint. It travels down the back part of your lower leg, running along the tibialis posterior muscle – a muscle in the back of your shin – alongside important blood vessels. This nerve passes near the inner side of your ankle in the tarsal tunnel, which is covered by a band of connective tissue called the flexor retinaculum.
In addition to the tibial nerve, the tarsal tunnel houses various tendons of muscles along with important blood vessels. After passing through the tarsal tunnel, the tibial nerve splits into two parts – the medial and lateral plantar nerves – which give feeling to the bottom of the foot.
The tibial nerve in the lower leg, before it reaches the tarsal tunnel, controls the movement of several muscles in the leg and foot. These include calf muscles like the gastrocnemius and soleus, as well as several foot muscles such as the flexor hallucis longus, flexor digitorum longus, and tibialis posterior. The medial plantar nerve, a branch of the tibial nerve, controls the movement of a several specific muscles in your foot.
The lateral plantar nerve controls the rest of the muscles on the bottom of the foot. These include several smaller muscles that help move individual toes and help maintain balance while standing or walking.
What Causes Tibial Neuropathy?
Tibial neuropathy is a condition that can happen if anything damages the tibial nerve in your lower leg. One major cause of tibial neuropathy is an injury to the ankle.
If you sprain or break your ankle, you might get scar tissue, bits of bone, or bone growths that can squash the tibial nerve. Similarly, an injury to the knee can damage the tibial nerve, like if the knee is knocked out of place from the back. Another source of damage to the tibial nerve is tarsal tunnel syndrome. This happens when the tibial nerve is crushed under a ligament (connective tissue that attaches bone to bone) in your foot. Other causes can be fatty tissue growths, tumors, fluid-filled cysts caused by arthritis, or any other thing that takes up space and puts pressure on your tibial nerve.
Foot correction surgeries like calcaneal osteotomy have a higher risk of causing tarsal tunnel syndrome. There have also been cases where tibial neuropathy happened because of unusual muscle shapes.
Risk Factors and Frequency for Tibial Neuropathy
Tibial neuropathy, a condition affecting the tibial nerve in the leg, is not a common diagnosis and its exact frequency remains uncertain. It can arise due to different reasons such as accidents causing injury, inflammation in the body, or in people with diabetes. It has been observed that those with rheumatoid arthritis, a type of inflammatory disorder, have a higher chance of having cases connected to tibial nerve damage in the foot’s tarsal tunnel.
Signs and Symptoms of Tibial Neuropathy
Tibial neuropathy is a condition that affects your tibial nerve and can cause discomfort and changes in sensation in your foot and toes. The pain often centers around the inside bump of your ankle, which is where the tibial nerve is located. This pain can worsen when you turn your foot inward. A common feature of this condition is that you will usually still have a normal sensation in your heel. This is because the heel’s nerve branches away from the tibial nerve before reaching the location of lesions in a condition known as tarsal tunnel syndrome.
One way to test for tibial neuropathy is through a technique called the Tinel sign. This involves tapping on suspected sites of nerve entrapment, or pressure. A positive Tinel sign means that this tapping brings back the pain or tingling sensation in the nerve distribution area. For example, this sign can be seen at the ankle if the pain source is from tarsal tunnel syndrome.
Another important aspect of the diagnosis is observing the patient’s walking pattern, including walking on heels, toes, and in a straight line. Overpronation, or excessive inward roll of the foot, may be observed when the patient walks, as this can stretch the tibial nerve. Muscle strength in specific leg muscles may also be assessed, particularly if a lesion is suspected in the upper part of the tibial nerve. This can be best gauged by observing the patient’s ability to perform one-legged calf raises.
However, when suspecting tarsal tunnel syndrome, assessing strength might not be reliable as it can be difficult to test the foot’s intrinsic muscles during an exam. Sensory testing, including assessments for pain response and light touch, should also be carried out. Reflex testing, like the patellar and Achilles reflexes, should also be done, even though these findings might not be specific and could indicate other conditions like radiculopathy and polyneuropathy. Furthermore, depending on the lesion’s location, these reflexes might not be affected, and in general, tarsal tunnel syndrome does not affect the Achilles reflex.
Testing for Tibial Neuropathy
If you have tarsal tunnel syndrome, which is a condition where the main nerve in your ankle becomes compressed, your doctor may use various tests to confirm this diagnosis. These tests help find out what’s causing your symptoms and rule out other potential conditions.
One of the first tests may be a plain X-ray of your foot. This can show if there are any fractures or bone growths (known as osteophytes) and it can also help your doctor check the overall structure of your foot.
Your doctor may also want to use a computerized tomography (CT) scan or a magnetic resonance imaging (MRI) scan. These scans can provide a more detailed picture of your ankle and foot, helping your doctor see any specific issues that might be causing damage to your tibial nerve (the main nerve in your ankle). These issues could include things like swelling, tumors, or bone spurs, which are bony growths that can form on the edges of bones.
An ultrasound, which uses sound waves to produce images, is another tool that your doctor might use. This test can be done quickly, right at your bedside, and is particularly helpful if your doctor suspects you may have tarsal tunnel syndrome. Ultrasound can also help rule out other possible causes of your symptoms, such as plantar fasciitis, a common cause of heel pain.
Next, electrodiagnostic testing might be done, which involves studies of nerve conduction (NCS) and electromyography (EMG). These tests are key in diagnosing damage to the tibial nerve. They work by measuring how well your nerves and muscles are communicating with each other. In some cases, the results of these nerve studies can be tricky to interpret, so it’s essential to compare the results from both sides of your body.
During EMG, your doctor will be looking for signs of abnormality in the muscles that are served by the tibial nerve. The test will show different signs depending on whether the injury to the nerve is recent or has been present for a long time.
While these tests can give your doctor a lot of information, diagnosing tarsal tunnel syndrome can still be challenging, especially in older patients or those who also have other nerve diseases. Because of this, your doctor will always look at the results of these tests along with your symptoms and medical history to make the most accurate diagnosis.
Treatment Options for Tibial Neuropathy
Treating tibial neuropathy, a condition that affects the nerve in the shinbone, depends on how severe the symptoms and nerve damage are. Physical therapy is an essential part of treatment for everyone with tibial neuropathy. The purpose of such a therapy plan is to strengthen the muscles helped by the tibial nerve. Techniques that can aid with this condition include nerve gliding exercises, kinesiology taping, electrical stimulation, and therapeutic ultrasound.
Studying how a person walks can shed light on factors contributing to the condition, such as walking with the foot overly tilted towards the inside, which can put more strain on the tibial nerve. For people who have this issue, a support insert can be placed in the shoe. Over-the-counter anti-inflammatory medicines can help manage pain and swelling, while prescription drugs including gabapentin, pregabalin, duloxetine, and amitriptyline are often used for nerve pain. Injecting a cortisone (steroid medicine) into the tarsal tunnel (channel in the ankle area) or another area where the tibial nerve is being squeezed can also help with symptoms.
When the condition is severe or resistant to these treatments, surgery might be necessary, particularly when muscle wasting or extreme weakness is present, as these are signs of axon damage in the nerve. The specific surgical technique used depends on where the tibial nerve is being compressed. Generally, the surgery involves releasing pressure on the tibial nerve by loosening the tissues into the foot to free the nerves that provide sensation to the bottom of the foot. The outcomes of the surgery are typically positive if there is a known and localized cause of compression that can be addressed.
What else can Tibial Neuropathy be?
When numbness, tingling, and pain are experienced in the foot, there could be various causes other than tibial neuropathy, which is a condition that affects your shinbone. Given how uncommon tibial neuropathy is, other causes should always be considered first. These might include:
- Multiple nerve disease (polyneuropathy) due to diabetes, alcohol use, or autoimmune disorders
- Nerve root disease in the lower back (lumbosacral radiculopathy), especially in the L5 and S1 distributions
- Sciatica or piriformis syndrome, which involves pinching of the sciatic nerve
- Plantar fasciitis, which is a common cause of pain on the bottom of the foot
- Morton neuroma, which causes a burning or tingling pain under the bones in the ball of the foot
- Neurogenic or vascular claudication, which may also cause foot pain
These conditions often get misdiagnosed as tibial neuropathy because their symptoms are very similar. Therefore, doctors need to carefully consider all of these possibilities and conduct the necessary tests to make the right diagnosis.
What to expect with Tibial Neuropathy
The outcome of tibial neuropathy, a condition affecting the nerves in your shinbone area, can differ greatly from person to person. If the condition is mild, it might respond well to simple treatments like therapy, custom shoe inserts (known as orthotics), and readily available anti-inflammatory medications.
However, if the symptoms are severe or they don’t get better, it’s important to continue investigating the cause. If the cause of this nerve condition is found and treated early, the patient is likely to recover.
As is common with other nerve damage, there can be lingering pain and a sensation of numbness depending on how badly the nerve is hurt. If the nerve injury is left untreated for a long time, it might result in considerable muscle weakness and shrinkage in the muscles around the shinbone area.
Surgery is less likely to be successful in cases of larger nerve injuries, or for patients who need to be operated on again.
Possible Complications When Diagnosed with Tibial Neuropathy
If tibial neuropathy, a condition impacting the nerve in your lower leg, isn’t treated or is very serious, it can lead to ongoing pain and weakness. This may result in the muscles served by the tibial nerve in the foot becoming weaker and smaller. When the issue is located higher up in the leg, it may cause weakness in the muscles used for pointing the toes downwards, like the calf muscles.
If someone needs surgery for tibial neuropathy, there can be complications afterwards, such as infection, bleeding, scar tissue forming, and issues with the wound healing. Even with surgery, some people may continue to experience symptoms of tibial neuropathy.
Common Issues:
- Ongoing pain and weakness
- Muscle reduction and weakening in the foot
- Weakness in toe-pointing muscles
- Surgical complications like infection
- Bleeding after surgery
- Formation of scar tissue
- Poor wound healing
- Persistent symptoms after surgery
Preventing Tibial Neuropathy
Teaching patients about their conditions is a key part in managing tibial neuropathy, which is a condition that affects the nerves in your legs. Though tibial neuropathy is not common, doctors usually check for more frequent conditions first before diagnosing it. Nonetheless, spotting it early is necessary to stop the nerve damage in the legs from getting worse. Physical therapy can be a form of treatment that works to improve your flexibility and strength.
