What are nerve injuries and neuromas?
A nerve consists of many nerve fibers that form a bundle. They are susceptible to mechanical stresses such as pressure or stretching and can be temporarily or permanently damaged as a result, so that they can no longer or only partially fulfill their function. Of course, nerves can also be injured by direct external impact, such as a cut. If nerve fibers are severed, they try to regenerate by sprouting, to reconnect to the other nerve end, so to speak. However, as the two ends retract when the nerve is severed, this is usually not successful and a nodular structure of nerve fibers and scar tissue (neuroma) forms. Apart from the fact that these fibers can no longer perform their function, they may cause discomfort.
Nerve injury and neuromas: causes and risk factors
Pressure, stretching or direct force are the main causes of nerve injuries. The superficial location of certain nerves (such as the ulnar nerve) makes them susceptible to external pressure damage. Excessive movements of the extremities, for example as a result of a fall, can cause nerves to be overstretched or even torn (e.g. axillary nerve when the shoulder is dislocated). The same can occur with severely displaced fractures. In the case of open injuries such as cuts or lacerations, nerves can be damaged directly. Neuromas occur when individual nerve fibers are severed.
Symptoms: Depend on the extent of the damage
The symptoms depend on the extent of the damage. Typical symptoms of pressure and stretch damage without tearing of nerve fibers are falling asleep, tingling and numbness in the area supplied by the affected nerve. The severity of these symptoms can range from barely noticeable to complete loss of sensitivity and movement/strength. If nerve fibers are torn, they immediately lose all function. Depending on how many nerve fibers are damaged, the symptoms are more or less pronounced. After the acute stage of an injury, chronic pulling, burning nerve pain (neuropathic pain) often occurs in addition to the above-mentioned deficits. In the area of neuromas, which naturally only occur after some time, hypersensitivity may occur in the affected supply area. Tapping on the neuromas through the skin produces unpleasant electrifying sensations. This can be very painful and restrictive for the people affected.
Nerve injuries and neuromas: diagnosis with us
A suspected diagnosis is made based on the patient’s medical history and clinical findings. Based on the pattern of sensory and motor function loss, it is often possible to narrow down which nerve has been injured. To confirm the diagnosis, the neurologist can carry out an electrophysiological examination to test whether and if so, how well the nerve still conducts electrical impulses. However, this examination is often only conclusive after a few weeks. In the case of open injuries, the nerve damage is often obvious. In rare cases, X-rays, ultrasound or MRI can be useful to determine the causes of nerve damage or the localization of neuromas.
Nerve injury and neuromas: prognosis
The prognosis of nerve injuries depends on the damage to the nerve. As long as there is no permanent damage, sensitivity and strength can fully recover. However, this can take several weeks to months. If a nerve is sutured or reconstructed, the nerve fibers ideally grow back about 1 mm per day. The expected recovery time can be estimated according to the distance from the site of damage to the end organ (muscle, skin area). As scarring inevitably occurs during surgery, this also happens during operations on and around nerves. Such scars can slow down regeneration, restrict it or even lead to new complaints. The success of surgical nerve reconstruction depends primarily on the age of the affected person and the delay between the damage and the operation. All in all, these are injuries that generally take a long time to heal.
If a nerve is permanently damaged, it may be possible to partially compensate for the loss by transferring the tendons from muscles that are still functioning (tendon transfer). However, such operations are always “rescue operations” that never lead to normal function.
Nerve injuries and neuromas: treatment
If pressure or stretching does not lead to permanent damage to the nerve fibers, the nerve recovers on its own. However, if nerve fibers are permanently damaged, the corresponding loss also persists. In these cases, an attempt can be made to replace the destroyed piece.