Physical Therapy for Genetic Disorders

Activities that cause significant pain, prolonged muscle fatigue, or deterioration in previously achievable movements are not recommended.

In the presence of substantial scapular instability, uncontrolled overhead resistance exercises should be avoided. Ankle dorsiflexor weakness increases the risk of falls when walking on uneven ground.

If eye closure is incomplete, ophthalmological assessment is required to prevent corneal injury. Respiratory impairment must also be considered when prescribing physical activity.

9.Recommendations for Patients and Families

Patients are advised to organize daily activities so as to minimize, where possible, the need to hold their arms above shoulder level for prolonged periods.

Placing frequently used items at a convenient height, using forearm supports, and adapting the workplace can make daily tasks considerably easier.

In cases of pronounced facial muscle weakness and incomplete eyelid closure, recommendations from an ophthalmologist for protecting the ocular surface should be followed.

Family members should recognize that muscle weakness that appears mild may substantially hinder certain activities. Assistance should aim to preserve the patients independence rather than completely replace their own efforts.

Periodic functional assessment allows timely adjustment of home exercises and selection of assistive devices.

10. Conclusion

Facioscapulohumeral muscular dystrophy (Landouzy–Dejerine) is distinguished by its characteristic distribution of muscle involvement, asymmetry of symptoms, and considerable variation in the rate of progression.

A central feature of rehabilitation is addressing shoulder-girdle function: preserving the ability to use the arms, compensating for scapular instability, and preventing secondary postural abnormalities.

Well-organized care makes it possible to focus on the motor functions that matter most for the individual patients independence in everyday life.

Vladimir Maletskyi | 36.6 — 366 Days a Year | Physical Therapy for Genetic Disorders

Chapter 5. Myotonic Dystrophy (Steinert)

Part I. Hereditary Muscle Diseases

Myotonic Dystrophy Type 1 (DM1)

1. General Characteristics of the Disease

Steinert myotonic dystrophy is a hereditary multisystem disease combining progressive muscle weakness with myotonia—abnormally delayed muscle relaxation after contraction.

The disease is caused by expansion of CTG trinucleotide repeats in the DMPK gene on chromosome 19. Inheritance is autosomal dominant. Symptoms may appear earlier and become more severe in successive generations, a phenomenon known as genetic anticipation.

Congenital, childhood-onset, classic adult-onset, and mild forms are distinguished. The severity of manifestations varies considerably.

Unlike many other muscular dystrophies, Steinert disease affects not only skeletal muscles but also the heart, respiratory system, endocrine system, and central nervous system. Rehabilitation must therefore account for systemic manifestations. The prevalence of myotonic dystrophy type 1 (DM1) varies considerably across regions. According to GeneReviews, the estimated worldwide average is approximately 1 in 20,000 people; the disease is more common in certain populations.

2. Clinical Presentation

A characteristic symptom is difficulty relaxing the hand after a forceful grip. The patient cannot immediately open the fingers after a handshake or holding an object. Repeated movement sometimes reduces myotonia, producing the warm-up phenomenon.

Muscle weakness often begins in the distal limbs, particularly the finger flexors and ankle dorsiflexors. Atrophy of the forearm, hand, and lower-leg muscles gradually develops.

Facial muscle weakness, ptosis, altered facial expression, and articulation difficulties are typical. The masticatory and swallowing muscles may also be involved.

Extramuscular manifestations include cardiac conduction disturbances, arrhythmias, cataracts, insulin resistance, gastrointestinal disorders, and pronounced daytime sleepiness.

The congenital form is associated with generalized hypotonia, respiratory disturbances, and delayed motor development. Diagnosis is confirmed by molecular genetic testing for CTG-repeat expansion in the DMPK gene.

3. Goals of Medical Rehabilitation

The primary goal is to preserve practical hand function and the patient's ability to perform precise everyday movements despite the combination of muscle weakness and myotonia.

When designing a program, the specialist identifies several priorities: improving control of grasping and releasing objects, maintaining limb muscle strength, preventing falls due to ankle dorsiflexor weakness, and preserving independence in self-care.

Additional goals include improving exercise tolerance, preventing respiratory complications, and identifying swallowing difficulties promptly.

Rehabilitation goals must take account of daytime sleepiness, cognitive characteristics, and cardiac status, as these factors may substantially affect the safety and outcomes of therapy.

4. Therapeutic Exercise

Therapeutic exercise in Steinert disease has a particular focus: in addition to maintaining muscle function, it must develop the ability to control the initiation and completion of movement.

Hand exercises include working with soft objects of different shapes, sequential finger flexion and extension, transferring small objects, and training grasp coordination. Prolonged maximal gripping should be avoided because it may worsen difficulty with relaxation.

Repeated low-intensity movements sometimes alleviate myotonia through the warm-up phenomenon. This transient improvement in relaxation must be distinguished from ordinary muscle fatigue.

Lower-limb exercises address lifting the forefoot, maintaining stability while turning, and negotiating small obstacles. When functional capacity is sufficient, graded walking and stationary cycling may be used.

Structured moderate-intensity aerobic and resistance training may improve muscle function, walking endurance, and certain quality-of-life measures in patients with DM1. However, the available studies remain limited in size; therefore, the program must be individualized after assessing cardiovascular status, the severity of fatigue, and the patient's response to physical exertion.

5. Massage and Device-Based Physical Therapy

Massage is considered primarily an adjunctive measure for associated pain and muscular discomfort. Its application requires an understanding of the differences between myotonic contraction, muscle weakness, and ordinary muscle tension.

Gentle massage techniques may be used when tenderness is present. Intense mechanical stimulation and painful techniques are inadvisable, especially if they provoke prolonged muscle contraction.

TENS may be used for symptomatic pain relief when independently indicated. The potential use of NMES must be assessed individually: its effectiveness specifically for correcting myotonia or strengthening affected muscles in DM1 is not sufficiently established.

Therapeutic ultrasound, infrared therapy, and magnetotherapy likewise do not specifically target the myotonic mechanism. Their use for associated pain requires consideration of expected benefits, contraindications, and the limitations of clinical evidence.

Particular caution is required with device-based procedures in patients with pacemakers, implantable defibrillators, or significant cardiac rhythm disturbances.

6. Orthopedic Rehabilitation

The most characteristic orthopedic problem is weakness of the ankle dorsiflexors, which prevents the patient from adequately lifting the forefoot during walking.

In such cases, ankle-foot orthoses are individually selected to facilitate safer limb advancement and reduce the risk of tripping.

For hand weakness, aids with enlarged handles, lightweight household tools, and adaptive devices for writing, eating, and personal hygiene may be used.

Selection of assistive devices must account for a characteristic feature of the disease: a patient may grasp an object relatively easily but have difficulty releasing it quickly.

When mobility is substantially reduced, mobility aids and modifications to the home environment are considered.

7. Respiratory and Cardiac Rehabilitation

Cardiac conduction disturbances are among the most serious risks in Steinert disease and may occur even when muscle weakness is moderate.

Patients require regular cardiology follow-up, including an ECG at least once a year. Holter monitoring, echocardiography, and additional investigations are performed when indicated. Significant conduction disturbances may necessitate pacemaker implantation.

Respiratory disorders may result from respiratory muscle weakness, impaired regulation of breathing during sleep, and reduced cough effectiveness.

When hypoventilation is suspected, respiratory function and sleep are assessed. Noninvasive ventilation and cough-assistance techniques are used when indicated.

Swallowing difficulties require assessment of aspiration risk and involvement of a swallowing specialist.

8. Contraindications and Limitations

Rehabilitation planning must consider the risks of arrhythmias, respiratory failure, aspiration, and pronounced daytime sleepiness.

Intensive physical exercise should not be prescribed before cardiac assessment in patients with suspected conduction disturbances or clinically significant arrhythmias.

Exercises involving prolonged maximal gripping and activities that markedly worsen myotonia, pain, or weakness require particular caution.

In patients with swallowing difficulties, exercise immediately after a large meal is inadvisable, especially in the supine position.

An important medical limitation is the increased risk of complications associated with anesthesia and sedation. Before any procedure involving anesthetic agents, the anesthesiologist must be informed that the patient has DM1.

9.Recommendations for Patients and Families

Daily activities should be organized with possible delays in muscle relaxation in mind. Patients should be given sufficient time to release objects safely, change body position, and initiate walking.

When using tools and household appliances, the possibility of unexpected difficulty opening the hand must be considered. Items that do not require prolonged forceful gripping are preferable.

Family members should watch for fainting, palpitations, pronounced daytime sleepiness, choking or coughing while eating, and signs of breathing disturbances during sleep.

Patients are advised to follow the agreed schedule of cardiology examinations and monitor associated endocrine disorders.

In congenital and childhood-onset forms, early motor intervention, speech therapy, and educational support are particularly important.

10. Conclusion

Steinert myotonic dystrophy requires a particular approach because motor impairments coexist with potentially serious systemic complications.

Its fundamental distinction from other hereditary muscle diseases is the combination of progressive weakness with impaired muscle relaxation.

The rehabilitation specialist must not only maintain physical activity but also teach the patient to use the hands safely, monitor stability during walking, and account for limitations caused by cardiac and respiratory disturbances.

Vladimir Maletskyi | 36.6 — 366 Days a Year | Physical Therapy for Genetic Disorders

Chapter 6. Emery–Dreifuss Muscular Dystrophy

Part I. Hereditary Muscle Diseases

Emery–Dreifuss Muscular Dystrophy (EDMD)

1. General Characteristics of the Disease

Emery–Dreifuss muscular dystrophy is a rare inherited neuromuscular disease characterized by a combination of early joint contractures, gradually developing muscle weakness, and cardiac involvement.

The best-known genetic forms are associated with changes in the EMD and LMNA genes, which encode proteins involved in maintaining the structure and function of the cell nucleus. X-linked, autosomal dominant, and rarer autosomal recessive inheritance patterns occur. According to GeneReviews estimates, the overall prevalence of Emery–Dreifuss muscular dystrophy is approximately 1.3–2 cases per 100,000 population. The X-linked form is less common, at approximately 0.13–0.2 cases per 100,000 people.

Clinical manifestations may begin in childhood, and restricted joint mobility sometimes becomes apparent before a decline in muscle strength. The severity of motor and cardiac abnormalities varies considerably, even among relatives with the same genetic variant.

A distinctive feature of EDMD is that relatively mild muscular symptoms do not rule out dangerous cardiac complications.

2. Clinical Presentation

The most characteristic findings are elbow contractures, shortening of the Achilles tendons, and restricted neck flexion. Patients find it difficult to straighten their arms fully, place their heels on the floor, or bend their heads forward.

Muscle weakness initially often affects the upper-arm regions of the upper limbs and the lower-leg muscles. This distribution is termed humeroperoneal. The shoulder and pelvic girdle muscles may become involved later.

As the disease progresses, gait disturbances, difficulty climbing stairs, restricted spinal movement, and postural changes develop.

Cardiac manifestations include conduction disturbances, atrial and ventricular arrhythmias, and cardiomyopathy. Dizziness, syncope, and reduced exercise tolerance may occur. Some patients develop severe arrhythmias without preceding pronounced complaints.

Diagnosis is based on the characteristic clinical presentation, cardiac evaluation, and molecular genetic testing.

3. Goals of Medical Rehabilitation

Unlike diseases in which progressive muscle weakness is the leading problem, early identification of contractures and limitation of their consequences are of primary importance in EDMD.

The main goals are:

maintaining elbow extension and functional ankle mobility;

preserving a safe range of motion in the cervical spine;

preventing gait abnormalities associated with Achilles tendon shortening;

maintaining available muscle activity without excessive loading;

preserving independence in dressing, walking, and everyday activities.

An additional goal is to organize rehabilitation with cardiac risk in mind. The physical activity plan is developed after assessment of cardiac function and the presence of rhythm disturbances.

4. Therapeutic Exercise

Therapeutic exercise in Emery–Dreifuss disease begins with an assessment of joint mobility. The specialist determines the severity of contractures, the condition of the Achilles tendons, and the nature of restrictions in neck movement.

Regular gentle range-of-motion exercises are central. For the elbows, smooth extension within tolerated limits and exercises aimed at preserving functional arm positioning are used.

When the Achilles tendons are shortened, cautious calf stretching, ankle dorsiflexion movements, and exercises with controlled heel loading are applied. Loading must not provoke pain or tendon injury.

When neck mobility is restricted, gentle active movements are performed within a safe range. Forced flexion and abrupt, forceful manual techniques are unacceptable.

After cardiac assessment, the program may include graded walking, low-resistance exercises, and aquatic activities. With marked contractures, aquatic exercise therapy enables movement under reduced axial loading.

Because evidence on optimal exercise intensity specifically in EDMD is limited, the specialist is guided by individual tolerance, movement quality, and cardiovascular status.

5. Massage and Device-Based Physical Therapy

In EDMD, massage may be used to relieve associated muscular discomfort, particularly in areas of compensatory overstrain resulting from restricted joint mobility.

Superficial and moderate soft-tissue techniques are preferred. Established structural contractures cannot be eliminated by intensive kneading or mechanical stretching.

For pain syndromes, the potential use of TENS is considered in light of the patient's cardiac status. NMES is not a primary method of correcting contractures; the appropriateness of stimulating individual muscle groups requires specialist assessment.

Infrared therapy and therapeutic ultrasound may be considered for separate symptomatic indications, but convincing evidence of their effectiveness specifically in EDMD is lacking. Magnetotherapy is assessed similarly.

Patients with implanted pacemakers or defibrillators require particular attention. Electrical stimulation and electromagnetic procedures may be used only after compatibility with the implanted device has been verified and the cardiologist has approved their use.

6. Orthopedic Rehabilitation

Orthopedic care in EDMD is directed primarily toward managing contractures, which may substantially limit motor function even when muscle strength is preserved.

In the early stages, individually fitted orthoses may be considered to maintain functional foot positioning and preserve the available range of motion.

Surgical correction may be considered for marked Achilles tendon shortening. Decisions take account of muscle status, gait, the degree of deformity, and the potential effect of surgery on the patient's stability.

Elbow contractures require separate assessment because restricted extension interferes with everyday activities. Orthotic management and surgery do not always provide lasting restoration of mobility.

With spinal rigidity and restricted neck movement, posture should be monitored and comfortable positions selected for work, rest, and sleep.

Assessment of cardiac and anesthetic risks is mandatory before orthopedic surgery.

7. Respiratory and Cardiac Rehabilitation

Cardiac involvement in EDMD poses an independent clinical threat and does not always correlate with the severity of muscle weakness.

According to GeneReviews, evaluation should include an ECG, Holter monitoring, and echocardiography at least once a year. If conduction disturbances or cardiomyopathy are identified, monitoring should be more frequent.

Some patients require implantation of a pacemaker or an implantable cardioverter-defibrillator. In certain genetic forms, particularly those associated with LMNA, the risk of dangerous ventricular arrhythmias persists even after implantation of a conventional pacemaker.

Clearance for physical training must therefore take account of the cardiologist's assessment and, when necessary, that of a cardiac electrophysiologist.

Respiratory function may deteriorate because of respiratory muscle weakness and restricted chest mobility. When findings are normal, pulmonary function testing is recommended every two to three years; when abnormalities are present, monitoring should occur at least annually.

In respiratory failure, specialized respiratory support methods are used, including noninvasive ventilation and assistance with ineffective coughing.

8. Contraindications and Limitations

The principal limitation in EDMD is the risk of serious cardiac complications. Intensive exercise is not prescribed to patients with unevaluated arrhythmias, syncope, or suspected cardiomyopathy until specialist assessment has been completed.

Abrupt manipulations, forced elbow extension, and excessive stretching of the Achilles tendons are unacceptable when managing contractures.

Marked cervical spine rigidity requires particular caution when transferring the patient, positioning them on a treatment table, and performing physical therapy procedures.

If palpitations, presyncope, chest pain, or unusual shortness of breath occurs, the session must be stopped immediately, followed by medical assessment.

Implanted cardiac devices must be considered when selecting device-based procedures. Cardiac assessment and individualized anesthetic planning are required before surgery.

9.Recommendations for Patients and Families

Patients should understand that contractures in EDMD may develop long before a substantial loss of muscle strength. Regular assessment of joint mobility is therefore necessary even when independent walking is preserved.

Home exercises must follow specialist recommendations and be performed without forced stretching. Particular attention should be paid to foot positioning, the ability to extend the elbows, and comfort during neck movements.

Family members are advised to watch for changes in gait, toe walking, difficulty dressing, and restricted head rotation.

Recognizing signs of possible cardiac involvement is equally important. Syncope, sudden palpitations, and unexplained reduction in tolerance of usual activity require medical evaluation.

Because the disease is inherited, relatives may be offered genetic counseling and, when indicated, cardiac screening.

10. Conclusion

Emery–Dreifuss muscular dystrophy is distinguished by the characteristic combination of early contractures, humeroperoneal muscle weakness, and potentially dangerous cardiac abnormalities.

A practical feature of rehabilitation is the need to begin preventing movement restrictions before pronounced muscle atrophy develops. At the same time, cardiac status determines the permissible limits of physical activity.

Successful care requires coordinated work by rehabilitation specialists, neurologists, orthopedists, and cardiologists, because preserving joint mobility and preventing cardiac complications are complementary but distinct goals.

Vladimir Maletskyi | 36.6 — 366 Days a Year | Physical Therapy for Genetic Disorders

Chapter 7. Spinal Muscular Atrophy (SMA)

Part II. Hereditary Disorders of the Nervous System

Spinal Muscular Atrophy (SMA)

1. General Characteristics of the Disease

Spinal muscular atrophy is a hereditary neuromuscular disease characterized by damage to the motor neurons of the anterior horns of the spinal cord and the progressive development of muscle weakness and atrophy.

The most common form is 5q-SMA, caused by biallelic pathogenic variants in the SMN1 gene on chromosome 5. Inheritance is predominantly autosomal recessive. The SMN2 gene partially compensates for the deficiency of SMN protein; its copy number influences disease severity, although it cannot precisely predict the course in an individual patient.

According to various epidemiological estimates, the incidence of 5q-SMA is approximately one case per 6,000–12,000 live births. Rates may vary depending on the population studied.

Traditionally, five clinical types are distinguished, ranging from prenatal onset (type 0) to adult onset (type IV). However, modern disease-modifying therapies alter the natural course of the disease, making the patient's actual motor status increasingly important when planning rehabilitation.

2. Clinical Presentation

The principal manifestation of SMA is symmetrical muscle weakness, usually more pronounced in the proximal parts of the limbs. Reduced muscle tone, diminished tendon reflexes, and restricted motor activity are characteristic.

In type I SMA, an untreated child does not achieve independent sitting; marked hypotonia, feeding difficulties, and respiratory disturbances develop early.

In type II SMA, the patient can sit independently but usually does not achieve independent walking. Scoliosis, contractures, and chest deformities frequently develop.