The sural nerve provides sensation to the foot & its entrapment can lead to pain in the foot area. Many time it is termed as sural neuritis or sural neuralgia.

It is one of the five nerves that go down through the center of the calf muscle. Its direction is through the back of the leg, going over the Achilles’ tendon and ending up in the little toe.

When compared to other nerves, the sural nerve is one of the minor ones, as it provides sensation for the outside of the foot, for the areas between the 4th and the 5th toes.

Why do I feel sural nerve pain?

The main function of the sural nerve aka short saphenous nerve is to carry the sensory messages to the nervous system. But certain foot injuries, surgeries or fascial thickening causes sural nerve compression which leads to sural nerve damage which results in the sural neuritis causing the numbness, burning pain or diminished sensation. [01] [02]

When irritated, the nerve may be capable of creating some pain and discomfort.

Causes

The common causes of sural neuritis includes –

  • Ankle surgeries.
  • Repetitive stress on foot.
  • Nerve compression due to tight footwear.
  • Nerve entrapment in scar tissues

Even though anyone could suffer from these problems, sometimes it has something to do with surgery in the area of the foot. Nerve pain after ankle surgery is common in many patients. [03]

When the cause is not surgery, the problem is something athletes may suffer from. It is because the area of their foot is at all times stressed. [04]

Also, because the nerve is located just under the skin, it is particularly susceptible to compression. Tight shoes usually put pressure on the Achilles’ tendon.

When the nerve is compressed between the tendon and the shoe, the compression can cause neuritis. [05]

Another cause of sural neuritis is entrapment. This happens when the nerve gets pulled and trapped in the scar tissue.

This is more serious than the pressure a shoe puts on the nerve. For instance, this kind of pain is much easier to relieve.Sural Nerve Pain Area Near Ankle

Via – Diabetic Peripheral Neuropathy

The scar tissue involved is often the result of surgery in that region of the foot, so the sural neuritis can be a negative side effect of surgery.

There are a few surgical interventions that may cause this kind of nerve pain.

From these, the most common are:

  • Ankle fracture surgery,
  • Fifth metatarsal surgery,
  • Flatfoot surgery,
  • Achilles’ tendon related surgeries.

This list is not that long, but it is a well-known fact that there is a risk of sural neuritis when these surgeries are being performed. [06]

This pain comes with additional symptoms. For example, you may feel numbing or tingling outside of the foot.

This won’t affect the way you are walking, but it can cause a lot of discomfort.

However, you must be careful as these symptoms may develop over time, and you may end up suffering from neuritis. Be careful when feeling this kind of pain, as many people associate it with the standard pain of being on your feet too much.

Diagnosis

Given that this is a specific form of irritation, in a specific area that is also small, it is not that difficult to diagnose this health problem.

With that being said, a specific test for neuritis has not yet been identified. Therefore, your doctor may need to engage in a process of symptoms-elimination.

This means the doctor will rule other causes until he or she identifies the problem. More than this, the nerve’s location makes it easier for the disease to be confused with Achilles tendon problems.

Many health practitioners are saying that neuritis can often be confused with Achilles tendinitis. On the other hand, this is more related to ankle pronation or supination and not nerve issues.tendinitis. On the other hand, this is more related to ankle pronation or supination and not nerve issues.

So luckily, there are physical symptoms that a medic may be able to observe and rule out in this situation.

Tinel’s test

One test to be done is known as the Tinel’s test. This calls for percussion at the site of the nerve, at the ankle. In case the percussion causes tingling, pins and electric shocks, the test is positive, which is a sign of neuritis. [07]

Other technical measures include radiography. After you have done radiography, you have rule out the problems with the bones in the area.

Radiography may pick up the signs of arthritis or other diseases that are more dangerous and more serious. You could also get a magnetic resonance imaging test, as well.

These tests are being used to rule out the issues you may have with the soft tissues in the area.

Nerve block’s

Lastly, your doctor may think of using diagnostic nerve blocks over the area. The nerve block only does what its name says, it blocks the sensation of pain and discomfort from being sent to the brain.

When the nerve is being paralyzed, there is only the remaining pain to be assessed. In case the pain is finally relieved just by putting the sural nerve to sleep, then it is clear, you may suffer from neuritis. [08]

Treatment

In case the self-care measures or medication are not working, the treatment for sural nerve pain is surgery.

The sural nerve will respond to cold temperatures, that’s why putting ice on the affected zone would only do good.

Before taking any measure, make sure your shoes are not the ones causing the problem. In case your footwear presses on the Achilles’ tendon, it is time to replace your footwear.

You could also start using an anti-inflammatory like ibuprofen. You will not only reduce the pain, but you will also reduce inflammation. These actions will relieve the stress on your sural nerve.

In case your doctor decides for steroid injections, you may want to use them. These will relieve the inflammation and also the stress on the nerve.

Finally, when no more options are left, it may be time for surgery. This will release the entrapped nerve, and other measures will no longer need to be taken.

Before we start to discuss what sural nerve entrapment is, we should recapitulate for a bit, and remember what the sural nerve is. As a matter of fact, we won’t recapitulate but add some new information about the sural nerve and how important it is in the body.

Also referred to as the short saphenous nerve, the sural nerve is located in the lower leg, close to the short saphenous vein.

This nerve is often used for biopsies and nerve grafts. The sural nerve conveys sensory information from the lower calf and outer foot.

If this nerve is damaged, the treatment may be the removal of the nerve, which can result in numbness of the ankle. However, the nearby nerves are going to grow in to compensate.

Because this nerve is just below the skin and it is not that required for essential bodily functioning, doctors often use it when a nerve biopsy is needed.

The biopsy is done with a local anaesthetic that is being injected locally. As guidance, the doctor will use the saphenous vein to guide him or her, and after that remove a small part of the nerve.

After the wound has been stitched and closed, the small part of the nerve will be taken to the laboratory and put under the microscope and examined for any nerve health issues.

As said before, the sural nerve is a peripheral nerve. Therefore, it is used to communicate with the brain and the spinal cord. Sural nerve damage is, in fact, a subclass of peripheral neuropathy.

Neurons and their types

Also known as nerve cells, the neurons are divided into 3 main categories: sensory, motor, and interneurons.

The sensory neurons are responsible for the pick up of sensory signals and taking them to the spinal cord and the brain.

The motor ones take commands from the brain and spinal cord and take them to the muscles and glands, telling them what to do.

All the neurons are made of three structural components: cell bodies, axons, and dendrites.

In the cell body, there is the nucleus and the metabolic center of the neuron. The axon carries the signals away from the cell body while the dendrites are short projections that carry signals coming into the cell.

Peripheral neuropathy and its types

There are a few forms of neuropathy:

  1. Mono-neuropathy.
  2. Multi-focal neuropathy
  3. Polyneuropathy.[09]

The name says by itself: the first type is caused by only one nerve malfunctioning while the other is caused by several nerves malfunctioning.

Medical experts have agreed upon the fact that the sural nerve is somehow involved in peripheral neuropathy, also known as polyneuropathy.

Isolated sural neuropathy is a very rare condition.

One “Muscle and Nerve” study says that trauma is the most common cause of sural nerve neuropathy. However, let’s talk about nerve entrapment.

Nerve entrapment

Oftentimes, athletes complain about leg problems. They are also talking about pain. Usually, these issues are due to entrapment of the sural nerve or other peripheral nerves. [10]

Obviously, we all know that leg pain can be caused by exercise or too much physical effort, but sometimes these problems may be of something else, such as nerve entrapment.

Once the doctor has ruled out the musculoskeletal problems, the vascular ones or the ones of compartment syndrome, the only symptoms remain the ones of nerve entrapment.

Non-neuronal causes of sural nerve pain

There are a few non-neuronal causes of sural nerve pain and they are as it follows:

Muscle strain

You may think the muscles cannot be hurt by overstretching, but they can.

The muscle that can be more often injured due to overstretching is tibialis anterior. The symptoms of a muscle stretch are swelling and inflammation.

This is why sometimes nerve pain can be confused with muscle pain and you may think you have a nerve problem when it is, in fact, a muscle issue.

Tendonopathy

This is a condition in which micro tears in the tendon are causing inflammation in the tissue surrounding it.

Tendonopathy pain is once again similar to sural nerve pain, so it is necessary to not confuse the two pains.

Chronic exertional compartment syndrome

This is an overuse condition that is a result of fascia around the muscles. It produces symptoms during the training and also 15 minutes after the training.

The pains are similar to the ones of nerve pain: needles and tightness in the lower leg. The diagnosis of this issue can be confirmed by using pressure testing after the patient has exercised.

Nerve entrapment syndromes

Nerve entrapment happens when the mechanical irritation is happening. Mechanical irritation refers to the fact that the nerve has become injured in an anatomical location that is vulnerable.

Oftentimes, nerve entrapment is similar to compartment syndrome, tendonopathy and also arterial entrapment. This issue may involve a combination of nerves.

Saphenous nerve entrapment

This can happen when conditions like bursitis, MCL injuries, and direct traumas are taking place. More than this, this damage can occur during surgeries like hamstring graft to deal with the reconstruction of the ACL, or varicose veins surgeries.

Sural nerve entrapment

When it comes to physical effort, this is a very rare cause of pain. However, it may still occur. Compression caused by lesions, scar tissue, thrombophlebitis, ganglia and also surgical trauma may lead to sural nerve entrapment.

The symptoms are very similar, if not identical, with the ones related to Achilles Tendonopathy.

The nerve will be damaged and inflamed and oftentimes, the pain is accompanied by some small muscle hernia. An additional symptom of this condition is post-exercise numbness.

How is sural nerve pain being addressed nowadays?

The nerves in our bodies “have their own ways to make us feel bad”. Being the central parts of our anatomy, the nerves are responsible for the way we are about the surroundings and the way we are surviving in this world.

This pain can be very bothering, not to mention it could bother anyone. For some, it is a pain they cannot live with. That’s why they need to go to the doctor and see what the problem is and how to address it.

Usually, medical experts prefer to address sural nerve pain with conservatory methods.

It is rare that a person needs surgical treatments for such an issue. Oftentimes, the sural nerve pain can be addressed only with ice and anti-inflammatory medicines.

As said earlier, you will need to get rid of all the shoes that may be keeping your legs tight. Certain ski boots and biking footwear can do this.

In the event that the nerve is entrapped, shots or physical therapy can help mobilize and separate the scar tissue. Surgery should be the last resort of sural nerve pain.

References:
[01] George K Paraskevas, Konstantinos Natsis, Maria Tzika, and Orestis Ioannidis. “Fascial entrapment of the sural nerve and its clinical relevance.” DOI: 10.5115/acb.2014.47.2.144
[02] Rbia N, Nijhuis THJ, Roukema GR, Selles RW1, van der Vlies CH, Hovius SER. “Ultrasound assessment of the sural nerve in patients with neuropathic pain after ankle surgery.” DOI: 10.1002/mus.25744
[03] Aki Fukuda, Akinobu Nishimura, Shigeto Nakazora, Ko Kato, & Akihiro Sudo. “Entrapment of Common Peroneal Nerve by Surgical Suture following Distal Biceps Femoris Tendon Repair.” DOI: 10.1155/2016/7909805
[04] Babwah T. “Sural nerve injury in a footballer related to blunt leg trauma.” DOI: 10.1080/15438627.2012.634728
[05] Raoul Saggini, Maurizio Migliorini, Simona Maria Carmignano, Emilio Ancona, Chiara Russo, Rosa Grazia Bellomo. “Inferior heel pain in soccer players: a retrospective study with a proposal for guidelines of treatment.” DOI: 10.1136/bmjsem-2015-000085
[06] Jaclyn Haugsdal, Jeremiah Dawson, MD, and Phinit Phisitkul, MD. “Nerve Injury and Pain after Operative Repair of Calcaneal Fractures: A Literature Review.” The Iowa Orthopaedic Journal. 2013;33:202-207.
[07] “Purpose, technique and evidence ot tinel’s test” https://www.physio-pedia.com/Tinel%E2%80%99s_Test
[08] NikolaiBogdukMD, PhD, DSc, Grad Dip Pain Med, FFPM(ANZCA)(Professor of Pain Medicine, University of Newcastle and Senior Staff Specialist, Royal Newcastle Hospital) “Diagnostic nerve blocks in chronic pain”. 10.1053/bean.2002.0252
[09] R.Hanewinckel, M.A.Ikram, P.A.Van Doorn. “Peripheral neuropathies”. DOI: 10.1016/B978-0-12-802973-2.00015-X
[10] Fabre T, Montero C, Gaujard E, Gervais-Dellion F, Durandeau A. “Chronic calf pain in athletes due to sural nerve entrapment. A report of 18 cases.”. https://www.ncbi.nlm.nih.gov/pubmed/11032224

Visit Link