Why does a compressed nerve cause pain?

Lower extremity nerve compression syndromes

Usually the compression of the nerves is caused by indirect causes. Mostly these are the consequences of broken bones, dislocations or malpositions of the feet, such as splay feet or flat feet. Nerve compression syndromes also occur in the context of rheumatoid arthritis, as tendons and ligaments can be inflamed and thickened. Tendon infections are occasionally caused by sporting or work-related overload. Metabolic diseases such as diabetes or kidney diseases can also lead to deposits in the tendons or their thickening and thereby narrowing of the nerve. However, nerve compression can also occur idiopathically without an external cause, as is often the case in the upper extremity of carpal tunnel syndrome.

The sciatic nerve coming from the spinal cord is painfully known to many patients due to the colloquial lumbago. This nerve gives off the femoral nerve and, as it continues along the leg, divides into the tibial nerve (tibial nerve) and the calf nerve (common peroneal nerve). These nerves can be disturbed at several particularly sensitive bottlenecks along the leg.

Branches of the femoral and sciatic nerves can be narrowed or injured at the knee joint, causing knee pain. Under certain circumstances, these complaints can be treated with a partial knee joint denervation according to Dellon. For details this hitherto little known operation we would be happy to advise you.

 

The tibial nerve runs through the Tarsal tunnel. This is a bony structure on the inner ankle that is covered by a tether. The nerve supplies the sole of the foot with feeling and innervates the small foot muscles.

Tarsal tunnel syndrome

At the Tarsal tunnel syndrome Compression of the tibial nerve leads to burning pain and sensory disturbances in the area of ​​the inner ankle, which, however, typically radiate towards the heel and sole of the foot and can be triggered and intensified by pressure or tapping on the area of ​​the inner ankle. The patients often also suffer from hypersensitivity (hyperesthesia) of the soles of the feet, possibly with accompanying paralysis of the foot muscles. The build-up of perspiration on the feet may be reduced.

Morton's neuralgia / Morton's metatarsalgia

On the nerve branches supplying the toes, external pressure can lead to nerve bulges, which then result in burning pain in the area of ​​the front sole of the foot. This clinical picture is called Morton's neuralgia or metatarsalgia (sometimes also called Morton's "neuroma", although it is not a "real" neuroma). Usually the space between the toes is 2/3 or 3/4 affected.

 

In the case of complaints on the back of the foot, the peroneal nerve (fibula nerve) is affected, which runs through the back of the foot under a crossed ligament of connective tissue and can be narrowed here, possibly facilitated by shoes that are too tight.

Another narrow point for the peroneal nerve is at the level of the fibula head, around which the nerve coming from the hollow of the knee has to "loop around". This is often affected by pressure, but also by injuries or operations in the knee area through swelling or direct injury. Here the muscles of the foot and toe lift, as well as the feeling between the 1st and 2nd toe, or, if only the sensitive part is affected, the feeling on the back of the foot.

 

Surgery of the peripheral nerves and the treatment of chronic pain that could be triggered by these nerves is a focus of our practice.
We would be happy to advise and examine you if you discover that the above-mentioned aspects apply to your problem.

Our flyer on the subject: Peripheral Nerve Surgery (PDF)