Symptoms

The symptoms of anterior tarsal tunnel syndrome manifest themselves as a painful sensation on the back of the foot and above the ankle joint. This pain can occur at rest and at night as well as under stress with radiation into the calf. Pressure pain is also characteristic.

In addition to the pain, paraesthesias occur in the area between the first two toes, since the N. fibularis profundus is responsible for the sensitive care there (lat. Interdigital space I + II). From a certain degree, the toe extensor muscles may even weaken due to compression of the motor nerve components.

This causes problems when walking. The symptoms of a posterior tarsal tunnel syndrome are very variable. In principle, there can be a failure of the motor or sensitive parts.

Often affected persons complain of numbness in the area of the sole of the foot, since this region is supplied by the nn. plantares. Further paraesthesia is the tingling in the toes.

Pain in the rear tarsal tunnel syndrome occurs mainly on the underside of the foot and on the inner ankle. The character of pain can range from burning and pulling to stabbing. The pain can be felt both at rest and under stress.

Sometimes a sleep-robbing nocturnal pain is reported. Isolated pain in the heel may indicate that a special nerve branch (R. calcaneus) supplying the heel region is affected. Long-lasting nerve compression can even lead to paralysis (=paresis) of the foot muscles.

In most cases, the symptoms increase with prolonged standing or walking. In tarsal tunnel syndrome, both feet do not often become numb. Very often a tarsal tunnel syndrome occurs during long sessions on the crosstrainer.

Both feet become numb especially in combination with buckling feet. In this case, in almost all cases an insole fitting after a treadmill analysis is sufficient to eliminate all symptoms. At the beginning, an attempt at a conservative (non-surgical) therapy is usually made.

The latter have proven to be of little or no help, contrary to conventional assumptions. If the symptoms persist despite such treatment, there is the option of surgery, in which decompression of the tibial nerve is the goal. For this purpose, the retinaculum flexorum spanning the tarsal tunnel is split, which makes more space available to the nerve again.

Painkillers,
Immobilization of the foot and
Shoe insoles.

Tapering aims to support muscular structures and joints in their function and to ensure better stability. Due to their elastic nature, there is no restriction of movement. Tapering is increasingly used for the conservative treatment of tarsal tunnel syndrome.Taping an ankle joint can relieve it and provide the body, for example, with better conditions for healing tendon sheath inflammation in the sense of faster decompression of the fibular nerve or tibial nerve.

The tape is applied along the course of the affected structures and thus also depends on whether anterior or posterior tarsal tunnel syndrome is involved. For optimal effectiveness, the tape should only be applied by trained specialists. Wearing insoles can be a first conservative therapy approach as well as the aftercare after a surgical intervention.

This includes not only relieving footwear but also physiotherapy and targeted training of mobility. The use of insoles is particularly useful if the cause of tarsal tunnel syndrome is a foot malposition such as the “buckling flat foot”. By wearing specially shaped insoles, the foot posture can be optimized to a certain extent, since the insoles attempt to imitate the normal foot posture.

In most cases, the insoles have a supporting arch on the medial, i.e. inner side of the foot, which can support the possibly weak arch of the foot. The goal is to improve the contact surface so that pressure and forces can be distributed more evenly and gently. In principle, one tries to alleviate the symptoms first with the conservative variant.

If there is no improvement after approx. 8 weeks or if the symptoms return more frequently after improvement, surgery should be considered. In the case of anterior tarsal tunnel syndrome, conservative therapy is less likely to help, so the indication for surgery is often given here.

In this case, the retinaculum extensorum inferius (ligamentum cruciforme) is severed to counteract the compression caused by space-consuming processes. Also in the case of posterior tarsal tunnel syndrome, which occurs much more frequently, failure to respond to conservative therapy is a reason for surgery. In order to exclude the suspicion of a ganglion or even a nerve tumor, clarification by MRI or neurosonography is necessary, since in this case a simple severing of the ligamentous structures to relieve pressure is not a long-term solution.

In general, the operation has two goals: firstly, to remove the constriction in the area of the tarsal tunnel and secondly, to ensure that the two nerve branches (Nn. plantares mediales and lateralis) can pass through the rough sole of the foot to the underside of the foot. Nowadays, the procedure can be performed minimally invasive under general anesthesia.

First of all, it is important to orientate oneself correctly in order to choose the best incision. Palpation of the pulse of the posterior tibial artery can be helpful here, as this runs through the tarsal tunnel together with the tibial nerve and tendon sections. The site to be operated on is then exposed through an incision in the skin and the retinaculum musculi flexorum pedis, a ligament-like structure between the medial heel bone and the inner ankle, is split.

This relieves and releases the compression. As mentioned, however, the two nn. plantares must also be relieved if necessary.

They each run separately on the sole of the foot in a muscle fascia of the abductor hallucis muscle. In order to counteract space-consuming processes, the fascia can be split in the corresponding area. The desired decompression can only occur if the nerve is exposed over a longer distance.

A plaster cast should not be applied after the operation, since both the fibular nerve and the tibial nerve heal better and faster if they can slide. If mobility is restricted, scarring of the tissue occurs. In addition, the muscle press must be able to work again for venous thrombosis prophylaxis.

It is therefore generally recommended that the foot be protected by wearing walking aids for 10 days, but still be moved easily and carefully. The operation has been proven to have good success rates, so that patients are completely pain-free again afterwards. Only slight sensitivity disorders can persist for a few days after the operation.

The most important thing in tarsal tunnel surgery is the previous and exact diagnosis. There are many possible causes of pain in the foot area, and therefore the impairment of the nerve must be determined by measuring the nerve conduction velocity or other neurological evidence, before an operation is performed.The main risk during a tarsal tunnel operation is that the surgical site will be directly affected by the occurrence. It is essential that this is mitigated in the first few days by using crutches or similar devices.

In addition, there is a risk of scarring of the surgical site, which would lead to a renewed operation-related constriction of the nerve. Furthermore, the nerve as well as the artery and vein run through the tarsal tunnel. If errors occur during the operation, these vessels may be injured, resulting in bleeding.

The most important thing is to protect the sole of the foot and the forefoot for the first few days after the operation. Of course, one should not completely refrain from any movement or walking for more than a few days, because otherwise the risk of leg vein thrombosis is too high. So most patients will be given certain blood thinners for a few days to reduce this risk.

In addition, there is always the risk of the muscles shrinking considerably if certain groups are not used for a long time. However, the exact duration of the healing process cannot be specifically predicted, as it depends heavily on the nerve’s ability to regenerate in the individual. It can take up to six months and may require a second operation, but depending on the conditions, it can also be significantly shorter.

Also, the inability to work after a tarsal tunnel operation depends entirely on the recovery of the patient. In most cases, the patient will be on sick leave for four to six weeks. However, this depends entirely on the circumstances of the operation.

Whether the left or right foot is affected can affect the permission to drive a car. If an unwanted scarring has occurred, it may be necessary to operate again, which also extends the sick leave. However, if you follow the rest and rest periods prescribed by the doctor, you will in most cases be able to return to work after about six weeks.

There are some exercises that can help strengthen the foot muscles and relieve nerve compression or prevent it from returning. However, these exercises should only be performed if the pain they cause is not too severe. It is important to perform the exercises regularly over a certain period of time so that they are really effective.

Most of these exercises can also be integrated into everyday life and performed in between. One of these exercises is called “swing”. This is about standing barefoot on your toes and “swinging” from there to your heels.

This should be done slowly, controlled and several times in a row. For another exercise, pick up a pencil or towel with your toes that is lying on the floor. You can also use exercises to loosen the calf muscles by stretching them.

In this way, the center of gravity is not concentrated on the ankle but is absorbed by the calf muscles. There are all sorts of strategies for this; one of the possibilities is to sit with a towel and place a sling around your forefoot and pull slowly and controlled on this sling so that your toes are pointing upwards. Bandages that are worn on joints can generally increase stability and thus ensure that discomfort is reduced and pain caused by strain is alleviated.

A bandage and the resulting stability can also be of great benefit in the case of tarsal tunnel syndrome. Even basic bad posture is limited or prevented by bandaging a joint. This is because nerve compression can also be caused by incorrect posture. Similarly, such incorrect postures can be compensated with insoles that shift the load to the outside of the foot instead of promoting the load on the nerve.