Essentials of Assessment
Rehabilitation Management and Treatments
Available or current treatment guidelines
There are no evidence-based guidelines for the surveillance and management of the common adult and adolescent-onset muscular dystrophies covered in this section: Emery Dreifuss Muscular Dystrophy (EDMD), facioscapulohumeral muscular dystrophy (FSHD), and myotonic dystrophy type 1 (DM1) and type 2 (DM2). There are, however, consensus guidelines that have been developed for myotonic dystrophy type 1 and FSHD, which are based on available evidence1,2. These guidelines include recommendations for the management of conditions associated with each organ system affected.
Consensus Guidelines for FSHD2
- Respiratory: Baseline pulmonary function testing (PFTs). Patients need routine PFTs if baseline is abnormal or if there the patient has any combination of clinical features that would impact pulmonary function (severe proximal weakness, kyphoscoliosis, wheelchair dependence, or comorbid pulmonary or cardiac disease). Patients with FSHD should be referred to pulmonology or sleep medicine if they have compromised pulmonary function (forced vital capacity < 60%) or symptoms of excessive daytime somnolence or non-restorative sleep. PFTs should be tested prior to any surgical procedure that will require general anesthesia
- Cardiac: Routine screening is not needed in the absence of overt signs or symptoms of cardiac disease
- Ophthalmologic: Patients with FSHD who have large deletions in D4Z4 should be referred to retinal specialist for dilated indirect ophthalmoscopy to evaluate for retinal vascular disease
- Auditory: Young children who have been diagnosed with FSHD should have hearing screens at diagnosis and then yearly until starting school
- Patients should be evaluated by physical therapy to elucidate mechanical contributors to musculoskeletal pain and provide strategies to minimize pain.
- NSAIDs are appropriate for acute pain. For chronic pain, anti-depressants or anti-epileptics are helpful.
- Surgical scapular fixation can be offered but must be considered alongside the patient’s overall muscle impairment, potential for gain in range of motion, rate of disease progression, and possible risks of surgery and of prolonged post-operative bracing
Consensus Guidelines for DM11
- Respiratory: Baseline pulmonary function testing, with testing roughly every six months thereafter. Cough assistance techniques should be implemented for any patient with ineffective cough (< 270 L/min). Non-invasive positive pressure ventilation may be needed for patients demonstrating signs of respiratory insufficiency or those with signs of nocturnal hypoventilation. Patients should be referred for a sleep study if they have prominent snoring, MIP < 60, or FVC < 50%.
- Cardiac: Patients should have annual or biennial 12-lead electrocardiogram to evaluate for arrhythmias or conduction abnormalities. Patients should be referred to a center experienced in the care of DM1 patients if they are experiencing cardiac symptoms, if they have an abnormal ECG or if they are over the age of 40 and have never had a cardiac evaluation.
- Ophthalmologic: Patients should be referred for yearly ophthalmologic exam to monitor for development of cataracts.
- Encourage moderate intensity exercise, including aerobic exercise and resistance training
- Mexiletine can be used to treat skeletal muscle myotonia. However, it is contraindicated in the presence of cardiac involvement
- Patients should be evaluated yearly by a multi-disciplinary team to assess function and mobility
- Gastrointestinal: Patients need regular screening for dysphagia and should be referred for formal evaluation and swallow study if they are exhibiting signs/symptoms of dysphagia. High fiber diet and adequate water intake are recommended to prevent constipation and diarrhea.
- Metabolic/endocrine: At diagnosis, patients need to have thyroid function (TSH and free T4), serum lipids, hemoglobin A1c, and hepatic enzymes checked. If normal, TSH, free T4, and serum lipids can be checked every 3 years. ADA guidelines for diabetic testing should be used to guide frequency of testing for hemoglobin A1c and fasting blood glucose. Hepatic enzymes should be checked annually. Gender-specific metabolic concerns should be addressed (e.g. menstrual regularity in women or erectile dysfunction in men).
- Obstetric/gynecologic: Women of childbearing age should be referred for genetic counseling. Pregnant women with DM1 need to be referred to a high-risk obstetrician for antenatal care. Extreme care is needed with sedation and anesthesia
At different disease stages
- Unfortunately, there are no disease-modifying treatments for these disorders, and interventions are focused on symptom management and complication prevention.
- One hallmark of EDMD is early contracture development. Physical therapy and other common contracture management and prevention strategies help to maintain range of motion and slow loss of function7.
- Questions regarding exercise in these diseases often arise because of the aberrant nature of the muscle tissue.
- In both DM1 and DM2, moderate or low intensity aerobic and resistance exercises are recommended and have not demonstrated harm when studied1,3,4. However, cardiac evaluation prior to a new exercise routine is recommended in DM1 and DM2.
- In FSHD, studies of strength training have shown some improvement in dynamic elbow flexor strength, and these have also failed to show harm.
- Overall, a focus on optimizing energy conservation and decreasing oxygen consumption is recommended for maximizing function and minimizing oxidative stress.
- Aerobic exercise is also recommended to improve cardiovascular health3,4,6.
- Anabolic supplements such as DHEA, IGF-1, and creatine have failed to show consistent benefit in improving strengthand are not recommended in any of these disorders7.
- Early management of these diseases should also include surveillance for complications, such as the cardiac, respiratory, gastrointestinal, endocrine, and ophthalmologic complications often seen in DM1 and, to a lesser degree, DM2 (see above)1,3,4. These complications often have effective management strategies which can increase patient function and quality of life, and they can markedly affect a patient’s ability to participate in rehabilitation.
- Early screening for all of these diagnoses should include labs such as vitamin D and calcium, DEXA, EKG, echocardiogram, and pulmonary function testing, in addition to evaluation and management by physical therapy, occupational therapy and speech therapy.
- Cardiac complications are common in the DMs and in EDMD, but these are rare and mild in FSHD. The most common complications are conduction disturbances leading to arrhythmias and cardiomyopathy4,5. These patients require referral to cardiology and yearly EKG. Pacemaker or implantable cardioverter placement is recommended in EDMD patients with any degree of heart block or bradycardia, because of the increased risk of sudden cardiac death7.
- In the DMs, myotonia often precedes weakness and can cause difficulties swallowing, prolonged grip, and pain, however they can effectively be treated with mexiletine (though mexilitine is contraindicated in the presence of cardiac abnormalities)1,3,4,6.
- Respiratory weakness is common, and patients may need BiPAP at night and cough assist for secretion clearance. CPAP is usually inappropriate. Excessive daytime sleepiness is more common in DM1 than DM2 and can be exacerbated by respiratory issues. Fatigue is common in both. Methylphenidate (Ritalin) and modafinil (Provigil) can be helpful in treatment3,4,6.
- Pain is a common feature in all of these disorders and can be managed using conventional non-pharmacologic methods (massage, chiropractors, warm baths, etc), as well as conventional pharmacologic agents (NSAID, acetaminophen, gabapentin, TCA’s etc). DM1 and DM2 pain may respond to low dose glucocorticoid, or mexilitine. However, given the chronic risks and co-existing respiratory muscle weakness, medications that suppress respirations, such as opioids, should be avoided3,4.
- Patients with DM1 typically have some cognitive impairment, deficits in recognition of facial emotion and avoidant or apathetic personality5. Neuropsychology testing can be helpful to better characterize their deficits and assist with developing individual educational plans (IEP) for adolescent patients.
- Vocational rehabilitation may also assist with finding appropriate employment options if significant cognitive impairment is present. It can also assist with recommendations for job modification with progressive disability.
- Speech therapy can address dysphagia that may develop over time.
- Orthotics may be needed to support function as weakness progresses. Ankle foot orthoses (AFOs) can be used to address foot drop and dorsiflexion weakness, and improve gait, balance and energy expenditure. Some patients with FSHD may also benefit from a corset-style thoracolumbar orthosis to facilitate better posture.
- Occupational therapy and assistive technology help optimize ADL care and activities and provide guidance on how to best utilize adaptive equipment. DME such as manual or powered wheelchairs may facilitate independence as functional gait declines. Home modifications for access and safety may require care teams to engage contractors and builders13.
- Surgical options for complications from these diseases do exist.
- Scapular fixation for FSHD patients with preserved upper arm strength, either by scapulodesis or scapulopexy, can improve shoulder appearance, function, exercise tolerance and pain6,9. However, it does cause some shoulder instability and decreased adduction and internal rotation. These patients will also need post-operative physical therapy to make use of the new range of motion.
- For EDMD, surgical correction of contracture is controversial due to the high incidence of recurrence5.
Pre-terminal or end of life care
- For all these patients, it is important to discuss advanced directives, family planning and patient-centered goals, particularly with regards to ventilation, as respiratory complications are the most common cause of mortality in DM1 patients.
- Though symptom management is the hallmark of treatment through these disease processes, those with late-stage disease also benefit from considerations of proper positioning, secretion management, and nutrition.
Coordination of care
The rehabilitation physician is ideally trained to lead the multidisciplinary team caring for these patients, given their expertise in real world functional optimization, neuromuscular physiology, and multidisciplinary care coordination for other chronic disorders. Because of these patients’ functional limitations, dedicated multidisciplinary muscular dystrophy clinics can further facilitate well-coordinated care by reducing geographic hurdles and providing a “one-stop shop” for evaluation and treatment by all of a patient’s providers.
Patient & family education
Education should include basic information on the type of muscular dystrophy, role for medications, reason for therapies, anticipated future care, referrals, equipment, and routine screenings specific to each diagnosis. All patients with newly diagnosed muscular dystrophy should consider genetic counseling to understand risks to future children and extended family members.
Measurement of Treatment Outcomes including those that are impairment-based, activity participation-based and environmentally-based
Given the emphasis on symptomatic and supportive measures in these patients, outcomes are measured in terms of strength, function and quality of life. Numerous validated assessments are commonly used in other muscular dystrophies and can be applied to EDMD, FSHD and DM. These include common impairment assessments such as the following:
- Six-minute walk test (6MWT) tests aerobic capacity and endurance
- North Star ambulatory assessment (NSAA) tests lower extremity function
- Brooke and Vignos Scales measure upper and lower extremity function
- Pulmonary function testing and the Borg Dyspnea scale assess respiratory symptoms
Other metrics assess patient participation in activities, such as the Pediatric Outcomes Data Collection Instrument (PODCI)11 or the Pediatric Evaluation of Disability Inventory (PEDI)12. Quality of life assessment tools that have been used in muscular dystrophy patients include, but are not limited to, the World Health Organization Quality of Life (WHOQOL 100) questionnaire and the Pediatric Quality of Life Inventory for adolescent patients.
Translation into Practice: practice “pearls”/performance improvement in practice (PIPs)/changes in clinical practice behaviors and skills
As this information is translated into practice, it must be emphasized that these muscular dystrophies are multi-organ diseases, that require multi-disciplinary, seamless, lifelong treatment, with focus on early screening, present deficits, and plans for future needs.
Cutting Edge/ Emerging and Unique Concepts and Practice
Investigational therapies for EDMD have been directed at the laminopathy subtype (EDMD2) since this subtype includes the largest proportion of patients. Pre-clinical studies have shown some promise, particularly with the cardiac phenotype. The mitogen-activated protein kinase (MAPK) pathway, via the extracellular-signal regulated kinase (ERK) branch, has been particularly studied5. Targeted molecular treatments, especially antisense oligonucleotide therapy, have shown promise for myotonic dystrophy in animal models, but human trials have been limited by toxicity6. Studies of targeted treatments for FSHD have focused on disrupting expression of DUX4 or blocking downstream effects of DUX49.
Gaps in the Evidence- Based Knowledge
Studies have shown no evidence that moderate exercise is harmful in these patients but specific recommendations for types of exercise to achieve optimal outcomes have not been established.
- Myotonic dystrophy Foundation. https://www.myotonic.org/sites/default/files/MDF_2018_CareConsiderationsDM1_2019_1_4.pdf
- Tawil R, Kissel JT, Heatwole C, Pandya S, Gronseth G, Benatar M; Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology; Practice Issues Review Panel of the American Association of Neuromuscular & Electrodiagnostic Medicine. Evidence-based guideline summary: Evaluation, diagnosis, and management of facioscapulohumeral muscular dystrophy: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology and the Practice Issues Review Panel of the American Association of Neuromuscular & Electrodiagnostic Medicine. Neurology. 2015 Jul 28;85(4):357-64.
- Ashizawa T, Gagnon C, Groh W et al. Consensus-based care recommendations for adults with myotonic dystrophy type 1. Neurol Clin Pract. 2018 Dec;8(6): 507-520.
- Benedikt Schoser B, Federica Montagnese F, Guillaume Bassez G et al. Consensus –based care recommnedations for adults with myotonic dystrophy type 2. Neurol Clin Pract. 2019 Aug;9(4):343-353; DOI: 10.1212/CPJ.0000000000000645
- Turner C, Hilton-Jones D. Myotonic dystrophy: diagnosis, management and new therapies. Curr Opin Neurol. 2014 Oct;27(5):599-606. doi: 10.1097/WCO.0000000000000128. PMID: 25121518.
- Statland J, Tawil R. Facioscapulohumeral muscular dystrophy. Neurol Clin. 2014;32(3):721-ix. doi:10.1016/j.ncl.2014.04.003
- Heller SA, Shih R, Kalra R, Kang PB. Emery-Dreifuss muscular dystrophy. Muscle Nerve. 2020;61(4):436-448. doi:10.1002/mus.26782
- Logigian EL, Martens WB, Moxley RT 4th, et al. Mexiletine is an effective antimyotonia treatment in myotonic dystrophy type 1. Neurology 2010; 4:1441 – 1448.
- Hamel J, Tawil R. Facioscapulohumeral Muscular Dystrophy: Update on Pathogenesis and Future Treatments. Neurotherapeutics. 2018 Oct;15(4):863-871. doi: 10.1007/s13311-018-00675-3. PMID: 30361930; PMCID: PMC6277282.
- Case, L., Apkon, S., Eagle, M., et al. Rehabilitation Management of the Patient with Duchenne Muscular Dystrophy. Pediatrics: Oct 2018; 142 (s2). https://doi.org/10.1542/peds.2018-0333D
- Gates, Philip E. MD; Campbell, Susan R. PhD Effects of Age, Sex, and Comorbidities on the Pediatric Outcomes Data Collection Instrument (PODCI) in the General Population, Journal of Pediatric Orthopaedics: March 2015 – Volume 35 – Issue 2 – p 203-209 doi: 10.1097/BPO.0000000000000233
- Haley SM, Coster WI, Kao YC, et al. Lessons from use of the Pediatric Evaluation of Disability Inventory: where do we go from here?. Pediatr Phys Ther. 2010;22(1):69-75. doi:10.1097/PEP.0b013e3181cbfbf6
- Wheelchair Provision for Children and Adults with Muscular Dystrophy and other Neuromuscular Conditions: Best Practices Guidelines, March 2011. Muscular Dystrophy Campaign. https://www.musculardystrophyuk.org/wp-content/uploads/2015/02/wheelchair-guidelines.pdf
Mary McClanahan, MD
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Stephanie Green, DO
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Blake Fechtel, MD
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