Post Polio Syndrome

Classification according to ICD-10
G14	Post Polio Syndrome
ICD-10 online (WHO version 2019)

The post-polio syndrome (also Myatrophia spinal postmyelitica chronic or postpoliomyelitische progressive spinal muscular atrophy , short PPS ) is a consequence of poliomyelitis disease infection and occurs several decades after infection. Symptoms are increasing tiredness, muscle and joint pain, and muscle weakness, which cannot be explained by other causes.

Preliminary remark

The paralytic form of polio leads to flaccid paralysis . These arise because the motor anterior horn cells in the spinal cord destroyed by the poliovirus no longer supply their associated muscle fibers. In the recovery phase following the acute infection phase, neighboring, more or less intact, motor anterior horn cells take over their tasks. New nerve cell extensions ( dendrites ) sprout and, as far as possible, supply the orphaned muscle fibers. There is a distinct, but usually incomplete, muscular recovery phase. This natural repair process works quite well. If such a cell previously had to supply a few muscle cells, it now has a few hundred or even a thousand to supply. The so-called " motor unit " and with it the area of responsibility and the metabolism of the nerve cell was however immensely enlarged. Clinically, there is a clear improvement in muscle strength and many affected people learn to move better or even to walk again in the following period.

Post Polio Syndrome (PPS)

After three to five decades (frequency peak at 35 years of age), but at least after 15 years of a stable state of strength and other physical abilities, a slow decrease in strength and endurance is often observed in patients who have gone through poliomyelitis other causes can be explained. The so-called post-polio syndrome occurs. Especially in the acute phase of polio, severely impaired and then well recovered muscle groups are affected. However, muscle groups that were apparently not affected by the acute poliomyelitis can also be affected. An atrophy (shrinkage) of the affected muscles may occur or increase. The extent of the progression of the weaknesses is estimated by Dalakas, an American researcher who has studied the disease extensively, at 1 percent per year. Reliable data are not available for this. Weaknesses that progress more rapidly must suggest other diseases. Patients usually notice that the stamina for certain activities is decreasing or they have difficulty coping with the activities of daily living they previously performed. People with trunk and leg musculature disorders may find it difficult to walk, or they may fall more often. All of them need a longer period of recovery after physical activity. In some cases, cramps of muscles or muscle groups also occur more frequently. In the area of the muscles, so-called fasciculations (muscle twitching) are observed, but they do not involve any movement of the extremities; they are limited to a few fibers of a muscle. The PPS prefers the male sex (male: female = 1.5: 1) around the age of five. In about 70% of patients who suffered poliomyelitis in childhood, symptoms such as new paralysis, abnormal exhaustion and pain reappear after the decades of stable phase. Today it is considered certain that PPS is an independent second disease. Older estimates assume around 120,000 people affected in Germany. However, more recent epidemiological calculations show up to 1.2 million PPS patients in Germany.

It is very likely to be assumed that the aparalytic (not associated with paralysis) cases were not recorded. Since the paralytic and non-paralytic forms only make up about 1 percent of the infections, a total of 2,694,000 to 5,388,000 poliomyelitis infected people can be expected. According to this, the abortive cases with 98 percent amount to 2,640,000 to 5,335,000 affected persons. The occurrence of PPS for the paralytic cases is at a risk of about 70 percent, for the aparalytic cases at a risk of about 40 percent.

Abortive cases (without symptoms of the central nervous system) can also lead to PPS with a risk of approx. 20%. As a result, a total of 558,000 to 1,105,000 cases of PPS can currently be expected in Germany. It must therefore be assumed that the number of PPS diseases is significantly higher than previously assumed.

In the literature there is an indication of PPS expectation in 28 percent of the total infected. It leads to a similar order of magnitude in the number of people affected.

definition

The post-polio syndrome has been known for over 100 years. The first attempts to explain its cause by Jean Martin Charcot , a French neuropathologist, appeared in the French medical literature in 1875. Why these late effects after poliomyelitis remained a dark and poorly explored area of medicine is still not entirely clear. Few diseases in the world today are as widespread or as intensively researched as poliomyelitis. Because of the rapid and dramatic onset of symptoms, poliomyelitis has been viewed as the classic example of an acute viral infectious disease. As a result, most of the scientific energy and resources have been focused on early coping and contraception, without any research area addressing the long-term effects. To date, paralytic poliomyelitis is still described in medical textbooks as a static or stable neurological disease. With the widespread use of vaccines, poliomyelitis quickly became a medical rarity in industrialized countries. However, poliomyelitis and its complications were only seemingly defeated. Because of the severe epidemics of the 1940s and 1950s and renewed neurological changes only 30 to 40 years later, thousands of people affected by polio did not encounter new problems until the late 1970s and early 1980s. During this time, however, the clinical knowledge about this disease from the epidemics had largely been lost.

PPS is a neurological disease that causes a whole range of symptoms. Because these symptoms tend to appear together, they are called a syndrome .

The term "post-polio syndrome" was coined around the time, in May 1984, when the first international post-polio conference was held in Warm Springs, Georgia. In the years that followed, there was a remarkable increase in the interest of researchers and clinicians in PPS, leading to a more precise definition, a better understanding of possible causes, and the development of more effective management.

causes

Poliomyelitis is a disease of the second motor neuron (the so-called α- motor neuron ). Some of these cells perish.

The causes of the PPS have not yet been finally clarified. The most likely cause is an overload and destruction of the remaining motor neurons, probably triggered by emotional (mental), physical (through overexertion) and / or metabolic (metabolism-related) stress on the nerve cells. Continued dysfunction (malfunction) of the motor neurons can already be determined during the phase of functional stability . If a certain threshold (destruction of more than 50–60% of the motor neurons) is exceeded, according to the prevailing teaching view, PPS occurs through decompensation (derailment) of the de- and re-innervation process that has existed since the acute polio. According to current knowledge, in addition to peripheral nerve damage, acute polio infection always results in damage to motor cells in central brain centers. This is why PPS is not an exclusively peripheral neuromuscular disease; the encephalic part (the part of the control centers in the brain) is often clinically much more significant. Since the damaged neural structures often work at or above their load limit even under normal everyday conditions, the decompensation is already predetermined and the point in time, depending on the previous damage, essentially only depends on the level of the load.

The most important thing, however, is to remember that if the symptoms are unclear, this may be the flare-up of a disease that has already been through but has long been suppressed. The likelihood of developing PPS correlates with the late age of onset of polio, the severity of the symptoms of polio, and the length of time the initial paralysis has resolved.

Symptoms

The symptoms of PPS are varied. The percentage of new health and functional problems that were reported in people in post-polio clinics is shown in Table 1. The most common problems are fatigue, weakness, and pain in muscles and joints. They lead to increased difficulty walking, climbing stairs, and getting dressed - activities that require repetitive muscle work.

Tab. 1 New health and functional problems with PPS

Symptoms	%	Area
Health problems
fatigue	85	86-87%
Muscle aches	80	71-86%
Joint pain	80	71-79%
weakness
in previously affected muscles	80	69-87%
in previously unaffected muscles	60	50-77%
Cold intolerance	45	29-56%
Atrophies	35	28-39%
Problems with activities of daily living
Go	75	64-85%
Climb stairs	70	61-83%
dress up	40	16-62%

Postpoliomyelitic progressive muscular atrophy (PPMA) is a renewed, usually slowly progressing muscle weakness with or without myalgia (muscle pain) and atrophy (muscle wasting) in muscles that were initially affected or were spared at the time, possibly with involvement of the bulbar (supplied by brainstem nerves) or respiratory muscles - or now only concerning these, especially in patients with residual palsy ( residual paralysis) in these muscle groups. The paralysis pattern thus usually corresponds to that of the previous polio and is not symmetrical, but rather a colorful mix, as in acute polio, and mostly emphasized proximally ( near the trunk). The paresis, which is always flaccid, can spread indiscriminately to other muscles not affected by the previous polio. This means that the poliomyelitis affected these muscles in the acute illness was so mild that the person affected, but also the nursing staff and doctors, did not even notice the involvement of these muscle groups. However, there has been so much loss of motor neurons that after many years of overload, new weaknesses can develop. Fasciculations , cramps and pseudohypertrophy (apparent thickening) of the muscles are possible. Additional reflex failures are also possible. Sensory disturbances in the area of the affected muscles are completely absent.

Chronic fatigue, fatigue, cold intolerance, sleep and breathing difficulties are also reported. It is typical that fatigue improves after a rest period of 30–120 minutes. In contrast to the chronic fatigue syndrome , fatigue in post-polio patients improves after short periods of rest and usually does not prevent them from exercising their profession. Concomitant cranial nerve paralysis can lead to swallowing disorders with an increased risk of aspiration (risk of choking) , respiratory insufficiency (failure of breathing), dysarthria (difficulty speaking) and hoarseness. These swallowing disorders are observed in around 30% of patients. But only some of these patients report complaints.

Breathing can also worsen. The patient notices that he is short of breath for longer than before after exertion. Especially with infections of the respiratory tract or after general anesthesia, this functional disorder can decompensate (derail), so that pronounced shortness of breath occurs even at rest. In the case of minor disorders, the impairment of breathing often only becomes noticeable as a nightly functional disorder in the form of so-called " sleep apnea ".

Diagnosis

Diagnosing PPS is extremely difficult. There are no specific test procedures that prove or exclude the presence of a PPS. In addition, it is sometimes difficult to clearly secure a previous polio. The PPS is therefore a clinical diagnosis and primarily a diagnosis of exclusion. That is, it requires the need to rule out other internal, neurological, orthopedic, and psychiatric disorders that could also explain the symptoms.

When making the diagnosis of PPS, there are a few considerations to consider. First, symptoms like pain and fatigue are fairly general and non-specific. Ruling out all possible causes is therefore impractical and can be associated with high costs. Second, there may be general medical, orthopedic, or neurological disorders that cause very similar symptoms. Even for the experienced clinician, deciding which symptoms are caused by PPS and which are caused by other disorders can be a challenge. The diagnosis is always based on a description of the symptoms and a detailed physical examination by the doctor.

According to Dalakas, the following inclusion criteria should be present for the diagnosis of postpolio syndrome:

a medical history (history) of acute paralytic poliomyelitis in childhood or adolescence
a partial (partial) recovery of the paresis (paralysis) with a period of neurological-functional stability for at least 15 years
residual (retarded), asymmetrical muscle atrophy (muscle wasting) and / or muscle weakness, areflexia (loss of nerve reflexes) and normal sensitivity (at least in one limb)
Develop new neuromuscular symptoms such as fatigue and weakness, and muscle and joint pain
Rule out other causes that could explain these symptoms, such as: B. Radiculopathies , Neuropathies and Arthritis as well
normal sphincter function (sphincter function).

Differential diagnosis

The differential diagnosis must (diagnosis rule out other diseases) and radiculopathy (nerve root disease), arthritis (joint degeneration), neuropathy (other nerve disorders, such as carpal tunnel syndrome ), ulnar (the forearm located) neuropathy and other neuropathies caused by the long term use of walking aids or Wheelchair and poor posture arise as causes of renewed paresis (paralysis) are ruled out.

A number of additional examinations are also carried out in this context. Depending on the symptoms, these include: electromyography , electroneurography , x-ray and / or computed tomography (CT) and / or magnetic resonance tomography (MRT) and, if necessary, CSF examinations (examinations of the nerve fluid). Also electro euro graphic studies (NCV, nerve conduction ) can yield important information. If, for example, there is clear evidence of damage to the sensitive nerve fibers responsible for feeling, which convey sensory information from the skin and joints in the direction of the spinal cord, then a disease other than PPS is to be assumed and the diagnosis should be expanded in order to provide targeted treatment can. With CT or MRI, weaknesses, for example caused by masses in the lumbar spine area with pressure on nerve roots, can be excluded.

A breathing disorder caused by a PPS can be clarified in the sleep laboratory. But other internal diseases such as thyroid dysfunction , anemia or heart failure can also be ruled out. Depressive disorders with the resulting weakness must also be considered. Patients with a condition after poliomyelitis can of course develop depression just like healthy people. However, the frequency of occurrence does not differ between the two groups.

Therapy principles

A causal (causal) therapy is still not known.

There is no specific therapy, especially drug therapy.

First and foremost, affected patients should avoid further excessive strain on paralyzed or weakened muscles. This means:

Take regular breaks and avoid exhaustion
give up or change stressful activities and activities
Use orthoses (walking splints), wheelchairs or orthopedic aids at least temporarily .
Physiotherapy . It represents a supporting pillar in the overall treatment concept, including: slowly building up, non-tiring muscle exercises, massages, heat applications, etc.
possibly psychotherapy with information and discussion offers, as well as support with emotional and psychosocial problems.
learning of your own limits and strategies to avoid further overload.

Cave

Post-polio syndrome patients tolerate a number of drugs poorly, such as B.

Narcotics
Muscle relaxants
Psychotropic drugs
Beta blockers
nonsteroidal anti-inflammatory drugs
some antibiotics (aminoglycosides, tetracyclines , gyrase inhibitors, etc.)
Fibrates
Statins
Antiallergic drugs
Novalgin

This does not mean that you are not allowed to give these drugs, but that you should consider the use of these drugs very carefully, whether they are really essential and cannot be replaced by other, better tolerated ones. Then you should definitely dose this medication much more carefully and possibly lower than usual.

The rule of two in post-polio syndrome

Usually, the drug dose should first be divided by two.
Postoperative ventilation must be carried out twice as long.
The recovery time must be calculated twice as long.
It takes twice as long to relieve pain.
The recovery time before possible discharge from the clinic must be estimated twice as long.
The recovery time at home and the time until you return to work, as well as the time until you feel “normal” again, is twice as long.

prophylaxis

Avoid physically strenuous activities. Plan daily routine with enough rest periods. Physiotherapy is not geared towards building muscle (maximum performance training), but rather on gentle muscle maintenance.

literature

MC Dalakas, H. Bartfeld, LT Kurland (Ed.): The Post-Polio-Syndrome. (= Annals of the New York Academy of Science, Vol. 753). 1995, ISBN 0-89766-918-5 .
LS Halstead, G. Grimby: The Post-Polio Syndrome. G. Fischer, Jena 1996, ISBN 3-437-31036-4 .
LS Halstead: The Treatment of Post Polio Syndrome. A guide to dealing with the long-term effects of poliomyelitis. Bundesverband Poliomyelitis e. V. 2002, ISBN 3-9804519-3-3 .
DK Lahiri (Ed.): Protective Strategies for Neurodegenerative Diseases. (= Annals of the New York Academy of Science, Vol. 1035). 2004, ISBN 1-57331-530-3 .
MA Weber, P. Schönknecht, J. Pilz, B. Storch-Hagenlocher: Postpolio syndrome. Neurological and psychiatric aspects. In: Neurologist. (2004); 75, pp. 347-354.