Becker muscular dystrophy (BMD) is a progressive X-linked recessive group of neuromuscular disorders that primarily affect boys due to an X-linked mutation in the DMD gene and the dystrophin gene on the X chromosome that results in progressive muscle degeneration and proximal muscle weakness.[rx][rx] The gene controls the production of the dystrophin protein; dystrophin provides structure to cells in skeletal and cardiac muscle.[rx] This condition is less common and less severe than Duchenne muscular dystrophy (DMD). The onset of symptoms is late compared to Duchenne muscular dystrophy, although it varies widely between 5 to 60 years of age. In an investigation done in 67 patients exercising a standard protocol, the milder group had been found ambulant till their forties or beyond and more severe group with the earlier loss of ambulation.[rx]
Another Name Becker Muscular Dystrophy
- Benign Juvenile Muscular Dystrophy
- BMD
- Progressive Tardive Muscular Dystrophy
- Muscular dystrophy, Duchenne and Becker types
- Muscular dystrophy, pseudohypertrophic
Causes of Becker Muscular Dystrophy
Becker muscular dystrophy is caused by a mutation in a protein called “dystrophin.” The defective gene is located in the Xp21.2 chromosome, and the defect is inherited as an X-linked recessive trait. Patients without a clear X-linked pattern of inheritance may have defects in other genes, affecting the dystrophin-associated glycoproteins. Becker muscular dystrophy has to be distinguished from other myopathies with muscle weakness as presenting symptoms.
- Duchenne muscular dystrophy – More severe and early onset than BMD. The patient becomes wheelchair-bound earlier, and the length of survival is shorter. Patients usually have lower dystrophin concentration.[rx]
- Polymyositis – This is the idiopathic inflammatory myopathy characterized by bilateral proximal muscle weakness may confuse this condition with BMD, but the absence of distal pseudohypertrophy helps in differentiating it from BMD.[rx]
- Spinal muscular atrophy – This is an autosomal-recessive inherited disorder with hyporeflexia, tongue fasciculations, weakness in bulbar, or brainstem muscles are more common but have less cognitive impairment. The absence of dystrophin gene mutation in a DNA probe provokes spinal muscular atrophy as an alternative diagnosis.[rx]
- Limb-girdle muscular dystrophy – This condition is hard to differentiate from BMD; however, calf muscle pseudohypertrophy is absent.[rx]
- Dilated cardiomyopathy – Muscular dystrophy results in cardiomyopathy, which is one of the most serious complications and the leading cause of mortality. But dilated cardiomyopathy can be a separate entity with a different genetic etiology or from other causes apart from muscular dystrophy.[rx]
- Emery-Dreyfuss muscular dystrophy – Early contractures and cardiac defects help to distinguish it from BMD. Humeroperineal muscle weakness and wasting begin in the first and second decades of life.[rx]
- Myasthenia gravis – Fluctuating skeletal muscle weakness simulate the clinical presentation of BMD, but facial weakness, ptosis, and diplopia are common. However, infrequent proximal muscle weakness alone may occur.[rx]
- Metabolic myopathies – Metabolic myopathies are the storage diseases caused by the deficiency of enzymes required for the metabolism of glycogen, lipids, and mitochondrial diseases. Most patients complain about muscle weakness and pain during physical activity rather than during rest.[rx]
Symptoms of Becker Muscular Dystrophy
Some symptoms consistent with Becker muscular dystrophy are:
- Muscle weakness, gradually increasing difficulty with walking[rx]
- Severe upper extremity muscle weakness[rx]
- Toe-walking[rx]
- Use of Gower’s Maneuver to get up from floor[rx]
- Difficulty breathing[rx]
- Skeletal deformities of the chest, and back (scoliosis)[rx]
- Pseudohypertrophy of calf muscles[rx]
- Muscle cramps[rx]
- Heart muscle problems[rx]
- Elevated creatine kinase levels in blood[rx]
- Waddling gait
- Mild intellectual impairment
- Breathing difficulties
- Swallowing problems
- Lung and heart weakness
- Calf deformation
- Limited range of movement
- Respiratory difficulty
- Cardiomyopathy
- Muscle spasms
- Gowers’ sign
- Chronic respiratory infections precipitated by weakness in the smooth muscle of the bronchioles.[rx]
- Impotence caused by gonadal atrophy, which is characteristically associated with myotonic dystrophy.[rx]
- It is common to possess dysphagia, which is esophageal muscle involvement.[rx]
- Myotonia is a term that describes the inability to relax muscles, which classically indicating as an inability to loosen one’s grip or release a handshake.[rx]
- As a pediatric disease, parents will often complain that their child is clumsy or becomes extremely weak quickly.[rx]
- The Gower sign is when subjects try to stand from a supine position, they march their hands and feet to each other).[rx]
- Weakness and stiffness of distal muscles are usually the presenting symptoms in adolescents with myotonic dystrophy.[rx]
Diagnosis of Becker Muscular Dystrophy
History and Physical
On physical examination, atrophy with pseudohypertrophy of calf muscles and occasionally quadriceps, hypotonia, hyporeflexia, fasciculations, Gower sign (use their hands and arms support to push them upright from squatting position), lumbar lordosis, shortening of Achilles tendons along with contractures of joints like knee, elbows, and hips are the common findings.[rx][rx] Pseudohypertrophy is due to the fibrosis and fatty replacement of atrophic muscles, which is a classical feature. Besides calf muscle hypertrophy of forearm muscle and tongue is also found in rare instances.
Laboratory Tests
When muscular dystrophy is suspected after history and examination, creatinine kinase level followed by dystrophin gene deletion analysis or muscle biopsy with dystrophin antibody staining is the mainstay of the laboratory studies to confirm the diagnosis.[rx] However, in most instances, muscle biopsy is avoided, and genetic testing is confirmatory.
- Blood and urine tests – can detect defective genes and help identify specific neuromuscular disorders. On microscopic examination, the hallmark of Becker muscular dystrophy is ongoing myofiber necrosis and regeneration. Active muscle fiber necrosis and cluster of basophilic regenerating fibers are more prominent in younger age. In contrast, myofiber splitting with necrosis, increased internal nuclei, fiber hypertrophy, fatty replacement, and endomysia fibrosis are conspicuous in older age.[rx][rx]
- Creatine kinase – is an enzyme that leaks out of the damaged muscle. Elevated creatine kinase levels may indicate muscle damage, including some forms of MD before physical symptoms become apparent. Levels are significantly increased in the early stages of Duchenne and Becker MD. Testing can also determine if a young woman is a carrier of the disorder.[rx] The level of serum aldolase an enzyme involved in the breakdown of glucose, is measured to confirm a diagnosis of skeletal muscle disease. High levels of the enzyme, which is present in most body tissues, are noted in people with MD and some forms of myopathy. [rx]
- Myoglobin – is measured when injury or disease in skeletal muscle is suspected. Myoglobin is an oxygen-binding protein found in cardiac and skeletal muscle cells. High blood levels of myoglobin are found in people with MD.
- Polymerase chain reaction (PCR) – can detect some mutations in the dystrophin gene. Also known as molecular diagnosis or genetic testing, PCR is a method for generating and analyzing multiple copies of a fragment of DNA.
- Serum electrophoresis – is a test to determine quantities of various proteins in a person’s DNA. A blood sample is placed on specially treated paper and exposed to an electric current. The charge forces the different proteins to form bands that indicate the relative proportion of each protein fragment. [rx]
- Exercise tests – can detect elevated rates of certain chemicals following exercise and are used to determine the nature of the MD or other muscle disorders. Some exercise tests can be performed bedside while others are done at clinics or other sites using sophisticated equipment. These tests also assess muscle strength. They are performed when the person is relaxed and in the proper position to allow technicians to measure muscle function against gravity and detect even slight muscle weakness. If weakness in respiratory muscles is suspected, respiratory capacity may be measured by having the person take a deep breath and count slowly while exhaling.[rx]
- Genetic testing – looks for genes known to either cause or be associated with inherited muscle disease. DNA analysis and enzyme assays can confirm the diagnosis of certain neuromuscular diseases, including MD. Genetic linkage studies can identify whether a specific genetic marker on a chromosome and a disease are inherited together. They are particularly useful in studying families with members of different generations who are affected. An exact molecular diagnosis is necessary for some of the treatment strategies that are currently being developed. Advances in genetic testing include whole-exome and whole-genome sequencing, which will enable people to have all of their genes screened at once for disease-causing mutations, rather than have just one gene or several genes tested at a time. Exome sequencing looks at the part of the individual’s genetic material, or genome, that “code for” (or translate) into proteins. [rx]
- Genetic counseling – can help parents who have a family history of MD determine if they are carrying one of the mutated genes that cause the disorder. Two tests can be used to help expectant parents find out if their child is affected.
- Amniocentesis – done usually at 14-16 weeks of pregnancy, tests a sample of the amniotic fluid in the womb for genetic defects (the fluid and the fetus have the same DNA). Under local anesthesia, a thin needle is inserted through the woman’s abdomen and into the womb. About 20 milliliters of fluid (roughly 4 teaspoons) is withdrawn and sent to a lab for evaluation. Test results often take 1-2 weeks.
- Chorionic villus sampling, or CVS – involves the removal and testing of a very small sample of the placenta during early pregnancy. The sample, which contains the same DNA as the fetus, is removed by a catheter or a fine needle inserted through the cervix or by a fine needle inserted through the abdomen. The tissue is tested for genetic changes identified in an affected family member. Results are usually available within 2 weeks. [rx]
- Alanine Aminotransferase (ALT, SGPT) – The normal range in males is 10 to 40 U/L. The normal range in females is 8 to 35 U/L; it is elevated in muscular dystrophy.[rx]
- Aldolase (Serum) – The normal range is 0 to 6 U/L. It is elevated in muscular dystrophy but decreases in later stages of muscular dystrophy.[rx]
- Arterial Blood Gases (ABG) – Normal ranges: PO2 is 75 to 100 mmHg; PCO2 is 35 to 45 mm Hg; HCO3- is 24 to 28 mEq/L; pH is 7.35 to 7.45. Respiratory acidosis can develop if there are defects in muscles involved in respiration.[rx]
- Aspartate Aminotransferase (AST) – Normal ranges from 0 to 35 U/L. Elevated in muscular dystrophy.[rx]
- Creatine Kinase (CK, CPK) and Creatine Kinase Isoenzymes (CK-MB and CK-MM) – Normal ranges from 0 to 130 U/L. Elevated in muscular dystrophy (hyperkalemia).[rx] The serum enzymes, especially creatine phosphokinase (CPK), is increased to more than ten times normal, even in infancy and before the onset of weakness.[rx][rx] Serum CK levels are invariably elevated between 20 and 100 times normal in Duchenne muscular dystrophy.[rx] The levels are abnormal at birth, but values decline late in the disease because of inactivity and loss of muscle mass.[rx] Elevated CPK levels at birth are diagnostic indicators of Duchenne muscular dystrophy.[rx]
- Lactate Dehydrogenase (LDH) – Normal ranges from 50 to 150 U/L. Elevated in muscular dystrophy. LDH 4: 3 to 10%, LDH 5: 2 to 9%.[rx]
- Urinalysis (UA) – Glucose in urine is commonly associated with muscular dystrophy due to the high incidence of diabetes mellitus within this population.[rx] Myoglobinuria may also be present.[rx]
- Liver function tests – for transaminases, pulmonary function tests, and spinal radiographs to follow the progression of scoliosis are also important but less important.
Radiographic Tests
- Magnetic Resonance Imaging (MRI) – Coronal T1 weighted MRI may confirm the nonuniform fatty atrophy.[rx] There will be a relatively normal sartorius. Lateral radiographs may show cavus foot deformity and diffuse osteopenia.[rx] The sagittal view will show diffuse fat replacement of the gastrocnemius & semimembranosus muscles. These changes contribute to the prominent calves typical of affected children.[rx]
- Computerized Tomography (CT) – Axial CT shows denervation hypertrophy of the tensor fascia lata. The muscle becomes enlarged with an increase in intramuscular fat.[161]
Other Tests
- Chromosomal Analysis – DNA testing for common mutations and chromosomal analysis can now rule out Down syndrome, myotonic dystrophy, and other disorders. In both Becker and Duchenne dystrophies, the DNA deletion size does not predict clinical severity.[rx] [rx]
- Electrocardiogram (ECG) – Often, patients will have annual echocardiograms to stay ahead of any developing cardiomyopathy. This study will demonstrate atrial and atrioventricular rhythm disturbances. The typical electrocardiogram shows an increased net RS in lead V1; deep, narrow Q waves in the precordial leads.[rx] A QRS complex too narrow to be right bundle branch block; and tall right precordial R waves in V1.[rx] Dominant R wave in lead V1 is the best clue to the actual diagnosis.[rx] Normal PR interval, QRS duration.
- Electromyography (EMG) – Allows assessment for denervation of muscle, myopathies, and myotonic dystrophy, motor neuron disease. EMG demonstrates features typical of myopathy.[rx] Clinical examination, electromyography changes are found in almost any muscle: waxing and waning of potentials termed the dive bomber effect.[rx]
- Genetic Testing – A definitive diagnosis of muscular dystrophy can be established with mutation analysis on peripheral blood leukocytes.[rx] Genetic testing demonstrates deletions or duplications of the dystrophin gene in 65% of patients with Becker dystrophy, which is approximately the same percentage as in Duchenne dystrophy.[rx] [rx]
- Immunocytochemistry – A definitive diagnosis of muscular dystrophy can be established based on dystrophin deficiency in a biopsy of muscle tissue.[rx] Also, staining of muscle with dystrophin antibodies can demonstrate the absence or deficiency of dystrophin localizing to the sarcolemmal membrane.[rx] DIsease carriers may demonstrate a mosaic pattern, but dystrophin analysis of muscle biopsy specimens for carrier detection is not reliable.[rx]
- Immunofluorescence testing – can detect specific proteins such as dystrophin within muscle fibers. Following the biopsy, fluorescent markers are used to stain the sample that has the protein of interest.
- Electron microscopy – can identify changes in subcellular components of muscle fibers. Electron microscopy can also identify changes that characterize cell death, mutations in muscle cell mitochondria, and an increase in connective tissue seen in muscle diseases such as MD. Changes in muscle fibers that are evident in a rare form of distal MD can be seen using an electron microscope.[rx]
- Nerve conduction velocity test – measure the speed and strength with which an electrical signal travels along a nerve. A small surface electrode stimulates a nerve, and a recording electrode detects the resulting electrical signal either elsewhere on the same nerve or on a muscle controlled by that nerve. The response can be assessed to determine whether nerve damage is present. Repetitive stimulation studies involve electrically stimulating a motor nerve several times in a row to assess the function of the neuromuscular junction. The recording electrode is placed on a muscle controlled by the stimulated nerve, as is done for a routine motor nerve conduction study.[rx]
- Muscle Biopsy – The muscle biopsy shows muscle fibers of varying sizes as well as small groups of necrotic and regenerating fibers. Connective tissue and fat replace lost muscle fibers. Muscle biopsy usually shows nonspecific dystrophic features, although cases associated with FHL1 mutations have features of myofibrillar myopathy.[rx] Muscle biopsy shows muscle atrophy involving Type 1 fibers selectively in 50 percent of cases.[rx]\
- Polysomnogram – Excessive daytime somnolence with or without sleep apnea is not uncommon. Sleep studies, noninvasive respiratory support (biphasic positive airway pressure [BiPAP]), and treatment with modafinil may be beneficial.[rx]
- Slit Lamp – An examination for cataracts that may be present in patients with muscular dystrophy.[rx]
- Western Blot – A diagnosis of Duchenne dystrophy can also be made by Western blot analysis of muscle biopsy specimens, revealing abnormalities in the quantity and molecular weight of dystrophin protein. On Western blot, Becker muscular dystrophy individuals dystrophin levels will appear normal, although the protein itself is abnormal; this is in comparison to Duchenne muscular dystrophy affected individuals who have a significantly decreased dystrophin on Western blot.[rx]
Treatment of Becker Muscular Dystrophy
Becker muscular dystrophy has no curative treatment, and supportive therapy, along with rehabilitation, is the mainstay of treatment. Many clinical trials for gene therapy are still in progress.
Non-Pharmacological treatment
- Assisted ventilation – is often needed to treat respiratory muscle weakness that accompanies many forms of MD, especially in the later stages. Air that includes supplemental oxygen is fed through a flexible mask (or, in some cases, a tube inserted through the esophagus and into the lungs) to help the lungs inflate fully. Since respiratory difficulty may be most extreme at night, some individuals may need overnight ventilation. Many people prefer non-invasive ventilation, in which a mask worn over the face is connected by a tube to a machine that generates intermittent bursts of forced air that may include supplemental oxygen. Some people with Duchenne MD, especially those who are overweight, may develop obstructive sleep apnea and require nighttime ventilation. Individuals on a ventilator may also require the use of a gastric feeding tube.
- Supportive Bracing – This helps to maintain normal function as long as possible proper wheelchair seating is essential. Molded ankle-foot orthoses help stabilize gait in patients with foot drop.[rx] Lightweight plastic ankle-foot orthoses (AFOs) for footdrop are extremely helpful. Footdrop is easily treatable with AFOs.[rx] Bracing may be performed for function; for example, dorsiflexion of the feet with ankle-foot orthotics to prevent tripping or to provide support and comfort.[rx]
- Supportive Counseling – Some forms of muscular dystrophy may be arrested for prolonged periods, and most patients remain active with a normal life expectancy.[rx] Thus, vocational training and supportive counseling are important to provide the information necessary to plan their future.
- Genetic Counseling — Genetic counseling is recommended.[rx] With X-linked inheritance, male siblings of an affected child have a 50% chance of being affected, and female siblings have a 50% chance of being carriers. If the affected individual marries and has children, all daughters will be carriers of this X-linked recessive disorder. Genetic counseling should be offered to the mother, female siblings, offspring, and any maternal relatives.
- Cell-based therapy – The muscle cells of people with MD often lack a critical protein, such as dystrophin in Duchenne MD or sarcoglycan in some of the limb-girdle MDs. Scientists are exploring the possibility that the missing protein can be replaced by introducing muscle stem cells capable of making the missing protein in new muscle cells. Such new cells would be protected from the progressive degeneration characteristic of MD and potentially restore muscle function in affected persons.
- Gene replacement therapy – Gene therapy has the potential for directly addressing the primary cause of MD by providing for the production of the missing protein. Hurdles to be overcome include determining the timing of the therapy (to possibly overcome the genetic defect), avoiding or easing potential immune responses to the replacement gene, and, in the case of Duchenne MD, the large size of the gene to be replaced. For those MDs with central nervous system consequences (congenital muscular dystrophy and myotonic dystrophy), researchers are developing and fine-tuning gene therapy vectors (a way to deliver genetic materials to cells) that can cross the protective blood-brain barrier.
Supportive Physiotherapy
Treatment may include physical therapy, respiratory therapy, speech therapy, orthopedic appliances used for support, and corrective orthopedic surgery. Treatment includes supportive physiotherapy to prevent contractures and prolong ambulation.[rx] Maintaining function in unaffected muscle groups for as long as possible is the primary goal. Although activity fosters maintenance of muscle function, strenuous exercise may hasten the breakdown of muscle fibers.[rx]
- Physical therapy can help prevent deformities, improve movement, and keep muscles as flexible and strong as possible. Options include passive stretching, postural correction, and exercise. A program is developed to meet the individual’s needs. Therapy should begin as soon as possible following diagnosis before there is joint or muscle tightness.
- Passive stretching can increase joint flexibility – and prevent contractures that restrict movement and cause loss of function. When done correctly, passive stretching is not painful. The therapist or other trained health professional slowly moves the joint as far as possible and maintains the position for about 30 seconds. The movement is repeated several times during the session. Passive stretching on children may be easier following a warm bath or shower. [rx]
- Regular, moderate exercise -can help people with MD maintain range of motion and muscle strength, prevent muscle atrophy, and delay the development of contractures. Individuals with a weakened diaphragm can learn coughing and deep breathing exercises that are designed to keep the lungs fully expanded.
- Postural correction – is used to counter the muscle weakness, contractures, and spinal irregularities that force individuals with MD into uncomfortable positions. When possible, individuals should sit upright, with feet at a 90-degree angle to the floor. Pillows and foam wedges can help keep the person upright, distribute weight evenly, and cause the legs to straighten. Armrests should be at the proper height to provide support and prevent leaning.
- Support aids – such as wheelchairs, splints and braces, other orthopedic appliances, and overhead bed bars (trapezes) can help maintain mobility. Braces are used to help stretch muscles and provide support while keeping the person ambulatory. Spinal supports can help delay scoliosis. Night splints, when used in conjunction with passive stretching, can delay contractures. Orthotic devices such as standing frames and swivel walkers help people remain standing or walking for as long as possible, which promotes better circulation and improves calcium retention in bones. [rx]
- Repeated low-frequency bursts of electrical stimulation – to the thigh muscles may produce a slight increase in strength in some boys with Duchenne MD, though this therapy has not been proven to be effective. [rx]
- Occupational therapy – may help some people deal with progressive weakness and loss of mobility. Some individuals may need to learn new job skills or new ways to perform tasks while other persons may need to change jobs. Assistive technology may include modifications to home and workplace settings and the use of motorized wheelchairs, wheelchair accessories, and adaptive utensils.[rx]
- Speech therapy – may help individuals whose facial and throat muscles have weakened. Individuals can learn to use special communication devices, such as a computer with a voice synthesizer.[rx]
- Dietary changes – have not been shown to slow the progression of MD. Proper nutrition is essential, however, for overall health. Limited mobility or inactivity resulting from muscle weakness can contribute to obesity, dehydration, and constipation. A high-fiber, high-protein, low-calorie diet combined with recommended fluid intake may help. Feeding techniques can help people with MD who have a swallowing disorder and find it difficult to pass from or liquid from the mouth to the stomach. [rx]
Medication
There is no specific treatment to stop or reverse any form of MD. The U.S. Food and Drug Administration (FDA) has approved injections of the drugs golodirsen and viltolarsen to treat Duchenne muscular dystrophy (DMD) patients who have a confirmed mutation of the dystrophin gene that is amenable to exon 53 skipping.
- Anti-Arrhythmics – The pharmacological treatment of patients with a prevalent involvement of the cardiac tissue conduction relies on the use of ACE-inhibitors and appropriate antiarrhythmic drugs. In the case of atrial arrhythmias, the preference is for drugs such as antiarrhythmics (flecainide, propafenone) and beta-blockers. [rx]
- Anti-Epileptics – Children need to be followed closely by neurologists. Management of epilepsy is necessary for some patients.[rx]
- Anti-Myotonics – The pain associated with muscle rigidity is greatly alarming in the patient.[rx] When myotonia is disabling, treatment with a sodium channel blocker such as phenytoin (100 mg orally three times daily), procainamide (0.5–1 g orally four times daily), or mexiletine (150 to 200 mg orally three times daily) may prove helpful, but the associated side effects, particularly for antiarrhythmic medications, are often limiting.[rx]
- Endocrine Management – In case of impaired growth and delayed puberty, advice from endocrinologists plays a crucial role in the development of the child.[rx] Progressive scoliosis and contracture require surgical intervention to prolong ambulation.[rx]
- Corticosteroid – deflazacort at a dose of 0.9mg/kg/day has been the mainstay of treatment.[rx][rx][rx] Corticosteroids should be started before physical disability and continue even after the loss of ambulation and in more severe cases.[rx] It is beneficial for improving pulmonary function, delays scoliosis (decreases the need for surgery), delaying the onset of cardiomyopathy, and prolongs survival.[rx][rx] Corticosteroid dose should be reduced by 25% to 33% in case of side effects.[rx]
- Nitric oxide – has become the drug of treatment in some cases to increase the blood supply to muscles through vasodilation.
- Non-Steroidal Anti-Inflammatory Drugs – Treatment involves the administration of non-steroidal anti-inflammatory drugs to decrease pain and inflammation.[rx]
- Glucocorticoids – administered as prednisone in a dose of 0.75 mg/kg per day, significantly slow progression of muscular dystrophy for up to 3 years.[rx] Some patients cannot tolerate glucocorticoid therapy; weight gain and increased risk of fractures, in particular, represent a significant deterrent.[rx] There is recent evidence that oral steroids early in the disease can lead to dramatically improved outcomes.[rx]
- Golodirsen (SRP-4053) – This drug is an antisense therapy used for the treatment of Duchenne muscular dystrophy. Patients need to have a confirmed mutation of the dystrophin gene to facilitate exon 53 skipping. It is FDA approved, but the evidence to support its use is not yet well established.[rx][rx]
Surgical Treatment
- Contracture Release – Surgical release of contracture deformities is used to maintain normal function as long as possible.[rx] Massage and heat treatments also may be helpful.
- Defibrillator or Cardiac Pacemaker – Cardiac function requires monitoring, and pacemaker placement may be a consideration if there is evidence of heart block.[rx] Individuals with either Emery-Dreifuss or myotonic dystrophy may require a pacemaker at some point to treat cardiac problems. Management of cardiomyopathy and arrhythmias may be life-saving.[rx] In patients with severe syncope, established conduction system disorders with second-degree heart block previously documented, or tri-fascicular conduction abnormalities with significant PR interval lengthening, consideration needs to be given towards placement of a cardiac pacemaker.[rx] An advanced cardiac block is also an indication to install a pacemaker.[rx]
- Shoulder Surgery – Individuals with facioscapulohumeral muscular dystrophy may benefit from surgery to stabilize the shoulder.[204]
- Spinal Correction – Scoliotic surgery is an option when curves exceed 20 degrees to prolong respiratory function or walking ability or both.[rx]
- Tendon or muscle-release surgery – is recommended when a contracture becomes severe enough to lock a joint or greatly impair movement. The procedure, which involves lengthening a tendon or muscle to free movement, is usually performed under general anesthesia. Rehabilitation includes the use of braces and physical therapy to strengthen muscles and maintain the restored range of motion. A period of immobility is often needed after these orthopedic procedures, thus the benefits of the procedure should be weighed against the risk of this period of immobility, as the latter may lead to a setback.
- Surgery to reduce the pain and postural imbalance – caused by scoliosis may help some individuals. Scoliosis occurs when the muscles that support the spine begin to weaken and can no longer keep the spine straight. The spinal curve, if too great, can interfere with breathing and posture, causing pain. One or more metal rods may need to be attached to the spine to increase strength and improve posture. Another option is spinal fusion, in which bone is inserted between the vertebrae in the spine and allowed to grow, fusing the vertebrae together to increase spinal stability.
- Tracheostomy – and assisted ventilation are needed for patients with respiratory failure, and treatment of cardiomyopathy with ACE inhibitors and beta-blockers can help prolong survival.[rx]
- Cataract surgery – involves removing the cloudy lens to improve the person’s ability to see.
Prevention
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Yearly influenza vaccine
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Pneumococcal vaccine (PPS 23)[rx]
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Assess for, in the presence of corticosteroid intake, weight gain, dysphagia, constipation, malnutrition or prior main surgeries
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Physical therapy to prevent muscle contractures. Promote daily or regular exercise, but if there is muscle pain, reduce activity intensity or frequency
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Monitor for serum calcium, phosphorus, alkaline phosphatase, 25-hydroxyvitamin D (per semester), magnesium, PTH, urine calcium, and creatinine; Dual-energy x-ray absorptiometry at age three and annually; spine x-rays; bone age, especially if under corticosteroid therapy[rx]
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Consider biphosphonates if there is a history of symptomatic vertebral fractures, not as prophylaxis
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Baseline pulmonary function tests and biannually along with pediatric pulmonologist if the patient uses a wheelchair, age 12, or has a reduction of vital capacity of less than 80%
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Family members or caregivers should be educated regarding manual ventilation bags, mechanical insufflation-insufflation devices.