Peroneal paresis results from mechanical pressure damage to the common peroneal nerve, which carries both motor and sensory nerve fibers of the lower leg. The leading symptom of paresis, in addition to steppage gait, is sensory disturbances in the area of the lateral lower leg. Treatment involves targeted physical therapy and sparing of the nerve in the knee area.
What is peroneal nerve palsy?
The common fibular nerve – the “common fibular nerve” – is also known as the peroneal nerve and is a derivative of the sciatic nerve. In addition to somatomotor fibers, the nerve carries general somatosensitive nerve fibers. The nerve tract extends medial to the biceps femoris muscle to the head of the fibula and travels into the fibularis lodge, where the nerve divides into the terminal branches superficial fibular nerve and profundal fibular nerve. The common fibular nerve supplies motor nerve fibers to some extensors of the lower leg, among others, and thus plays an important role in leg extension. The term peroneal paresis is used to refer to lesions of the common fibular nerve. Paresis is essentially paralysis of the muscles as can be caused by lesions of the motor nerve fibers. In addition to paralysis, sensory disturbances may occur as a result of a lesion on the common fibular nerve because the nerve also contains sensory fibers.
Causes
The common peroneal nerve is relatively exposed in the region of the fibular head. For this reason, the nerve is extremely susceptible to damage, especially in this area, as can occur as a result of mechanical pressure. Little muscle as well as fat tissue or rapid weight loss are risk factors for peroneal paresis. In most cases, however, the cause of the paresis is a fracture of the fibula. A poorly padded lower leg cast can also put pressure on the fibular head and the adjacent common peroneal nerve. In addition, peroneal paresis can occur as part of the compartment syndrome. Those who have little muscle and fat tissue can already cause damage to the nerve pathway by crossing their legs for long periods of time. In individual cases, ganglions, neurinomas, tumors and Baker cysts can also cause peroneal paresis. Common to all of the above causes is mechanical pressure on the exposed nerve pathway.
Symptoms, complaints, and signs
The common peroneal nerve – the “common calf nerve” – supplies the peroneus longus muscle – the “long calf muscle” – the peroneus brevis muscle – the “short calf muscle” – , the tibialis anterior muscle – the “anterior tibial muscle” – and the extensor digitorum longus muscle – the “long toe extensor” – as well as the extensor hallucis longus muscle – the “long big toe extensor” -, the extensor digitorum brevis muscle – the “short toe extensor” – and the extensor hallucis brevis muscle – the “short big toe extensor”- with motor nerve fibers. Sensory innervation of the nerve pathway plays a role for the lateral lower leg region and the dorsum of the foot. In peroneal palsy, patients suffer from partial or total failure of the common peroneal nerve, which usually causes paralysis of the foot elevator muscles and toe elevator muscles. The leading symptom of the clinical picture is therefore a stepping gait, and the foot can often only be ponated to a limited extent. In addition, because the affected nerve also carries sensory fibers, sensory disturbances often occur in the lateral lower leg and dorsum of the foot when pressure damage occurs. The severity of symptoms depends on the extent of mechanical damage.
Diagnosis and course of the disease
Diagnosis begins with a thorough history with neurologic examination. Usually, the damaged nerve in the area of the fibular head shows pressure dolence. This phenomenon is known as Tinel’s sign and gives the neurologist the first indication of peroneal paresis. Electroneurography reveals conduction delays. Differentially, the paresis must be differentiated from an L5 syndrome, which would additionally be associated with pain in the affected area and weakening of the tibialis posterior reflex. There is a favorable prognosis for patients with peroneal paresis. Depending on the extent of the damage, full muscle function can be restored within a few days to months.
Complications
Due to peroneal paresis, patients primarily suffer from various sensory disturbances and disturbances in sensitivity. The patient’s quality of life is significantly limited and reduced due to the disorders, so that there may be considerable restrictions and discomfort in everyday life. As a rule, it cannot be universally predicted whether a complete recovery will occur. Patients suffer primarily from movement restrictions, so that they may also be dependent on the help of other people in their lives. Pain in the knees or legs may also occur as a result of peroneal paresis and continue to have a negative impact on quality of life. The further course of peroneal palsy depends very much on the type and origin of the damage to the nerves. It cannot be universally predicted whether complete healing will then occur. As a rule, the treatment of this disease depends on the cause. Surgical interventions are possible. However, the affected person is also dependent on various therapies in order to regain mobility. The patient’s life expectancy is not negatively affected by peroneal paresis.
When should you see a doctor?
Peroneal paresis should always be evaluated by a physician. In the absence of an examination and medical treatment, peroneal paresis can lead to irreversible damage and complications that can make the affected person’s life much more difficult. A doctor should be consulted if there is severe pain in the feet and thus restrictions in movement. Especially after an accident, a doctor should be consulted if there is paralysis or pain in the foot or the back of the foot. The pain may also occur at night, causing sleep problems and irritability. Life expectancy itself is not usually negatively affected by peroneal palsy if the accident only affected the foot region. Peroneal paresis can be diagnosed by a sports medicine specialist, an orthopedic surgeon, or even in the hospital. However, further treatment depends greatly on the extent of the damage, so surgery may be necessary.
Treatment and therapy
Treatment of patients with peroneal palsy depends on the primary cause of the damage. Underlying diseases must be detected in the diagnostic process in order to apply causal therapy. If, for example, a tumor or a Baker’s cyst is responsible for the pressure damage, resection of the growth must be performed as quickly as possible. The sooner the pressure condition on the muscle is resolved, the more likely the patient will make a full recovery. If there is no underlying disease and the pressure damage is accidental, physiotherapy is the focus of treatment. Targeted physiotherapy sessions are used to restore muscle strength in the affected area. If the pressure damage to the nerve is extreme, a peroneal splint may be prescribed. Further pressure damage to the nerve must be urgently avoided. For this reason, patients are advised against kneeling activities, for example. Since pressure damage or at least strain on the common peroneal nerve can also occur in the course of certain movements or sports activities, the patient must be informed about permissible and impermissible types of movement. Principle sparing of the nerve is indicated for the period after the damage so that the nerve tracts can recover from the lesions. Electrostimulation of the damaged pathways may be a component of therapy in individual cases.
Outlook and prognosis
The further course of peroneal paresis cannot usually be predicted in general terms. This is very much dependent on how badly the nerves of the affected person have been damaged and whether they can be repaired again. However, an early diagnosis with subsequent treatment always has a very positive effect on the further course of the disease and can also prevent the occurrence of further complications or complaints. For this reason, in the case of peroneal paresis, the affected person should see a doctor as early as possible and also initiate treatment. If the disease is not treated, the affected nerves may die completely, resulting in permanent sensory disturbances or tingling.These complaints have a very negative effect on the quality of life of the affected person and can significantly limit it. The complaints can be alleviated and limited by measures of physiotherapy or physiotherapy. However, a complete cure is not always possible. In some cases, the discomfort can also be alleviated by electrical stimulation. Peroneal paresis does not limit the life expectancy of the affected person. It may also not be possible to restore the patient’s full muscle strength.
Prevention
Peroneal palsy can be prevented only to the extent that pressure damage to the common peroneal nerve can be avoided. Especially in the knee area, the nerve is extremely exposed. Therefore, kneeling activities and other stresses on the nerve in the knee region should be avoided for the prophylaxis of paresis. The same applies to crossing the legs. Peroneal paresis cannot be completely ruled out by these preventive measures, but the overall risk for the condition can at least be minimized by this approach.
Aftercare
In peroneal nerve palsy, patients usually have very few or no specific aftercare measures available to them. First and foremost, a physician should be consulted early to prevent further worsening of symptoms or other complications. The earlier a doctor is consulted, the better the further course of the disease usually is. Most sufferers of this disease are dependent on physiotherapy or physical therapy. Those affected should also perform the exercises from such therapy in their own homes in order to accelerate healing and expose the body to low levels of stress. As a rule, the activity that caused the peroneal palsy should be avoided, which can also be a sporting activity. Affected persons should ideally avoid kneeling. Sometimes they are dependent on the help of other people in everyday life. The disease usually does not reduce the life expectancy of the affected person. Sometimes patients also depend on psychological support to prevent depression or other psychological upsets.
Here’s what you can do yourself
For patients with peroneal nerve palsy, adequate rest of the knee is especially important. Heavy physical stress on the knee should generally be avoided. Sports activities should also be selected according to the needs of the organism. All sports that contribute to heavy use of the knee should be avoided. Among them are long-distance runners, athletics or ball sports. At the first symptoms and irregularities of the musculoskeletal system, it is essential to rest and take care of the knee. Learned techniques in physiotherapy, which contribute to a relief of the knee in everyday life, should be applied independently. In particular, locomotion or carrying and lifting heavy objects should be optimized. Since peroneal paresis leads to sensory and sensitivity disorders, it is particularly important to deal with the discomfort and inconvenience properly. The use of mental techniques as well as relaxation procedures have proven to be helpful for many of those affected. Through yoga or meditation, patients are able to better cope with the discomfort in their daily lives. Cognitive training also helps to reduce stress and to cope better with the disease emotionally. Since in some cases there is no complete recovery, it should be examined whether psychotherapy is used. This helps with mental lifestyle changes due to the change in circumstances.
