Guideline sources The following summarized guidelines for the evaluation and management of facioscapulohumeral muscular dystrophy are prepared by our editorial team based on guidelines from the American College of Chest Physicians (ACCP 2023), the Heart Rhythm Society (HRS 2022), the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM/AAN 2015), and the European Federation of Neurological Societies (EFNS 2011). 1 2 3 4 5 5 5 5 Definition Facioscapulohumeral muscular dystrophy is an autosomal dominant inherited disorder characterized by asymmetric and progressive weakness of the muscles of the face, scapular, and humeral muscles, followed by weakness of distal lower extremities and pelvic girdle. 5 Epidemiology Facioscapulohumeral muscular dystrophy is caused by a genetic abnormality with contraction of a part of a repeated sequence in the D4Z4 region on chromosome 4q35 and mutations in gene SMCHD1. 5 Disease course Clinical manifestations of facioscapulohumeral muscular dystrophy include progressive weakness of the facial, shoulder arm muscles, foot drop, asymmetrical abdominal weakness https://web.pathway.md/diseases/recgxQZ5z8X0KSiPX 1/4 6/29/23, 4:00 AM Facioscapulohumeral muscular dystrophy Pathway (Beevor's sign), paraspinal muscle weakness, bent-spine, limb-girdle patterns, asymptomatic atrial arrhythmias, hearing loss, retinal vascular changes, and respiratory involvement that leads to patients wheelchair-bound. 5 Prognosis and risk of recurrence Facioscapulohumeral muscular dystrophy is not associated with increased mortality. 5 Guidelines 1. Classification and risk stratification Severity prediction: recognize that patients with large D4Z4 deletion sizes (contracted D4Z4 allele of 10-20 kb) are more likely to develop a more significant disability, and at an earlier age, and symptomatic extramuscular manifestations. B 2. Diagnostic investigations Genetic testing: As per AAN 2015 guidelines, obtain genetic confirmation of facioscapulohumeral muscular dystrophy type 1 in patients with atypical presentations and no first-degree relatives with genetic confirmation of the disease. B As per EFNS 2011 guidelines, diagnose facioscapulohumeral dystrophy with molecular testing of respective genes without additional investigations in patients with the typical presentation and suggestive family history (a male patient with muscular dystrophy with an uncle having a similar phenotype). B Respiratory evaluation: As per ACCP 2023 guidelines, obtain pulmonary function testing to assist with management decisions in patients with neuromuscular disease at risk for respiratory complications. E Show 3 more As per AAN 2015 guidelines, obtain baseline pulmonary function testing in all patients with facioscapulohumeral muscular dystrophy. Monitor patients regularly if they have abnormal baseline pulmonary function test results or any combination of severe proximal weakness, kyphoscoliosis, wheelchair dependence, or comorbid conditions affecting ventilation. B Cardiac evaluation: As per HRS 2022 guidelines, consider obtaining cardiac evaluation, including physical examination, ECG, ambulatory ECG, and cardiac imaging (echocardiography or cardiac MRI), at diagnosis with periodic retesting in patients with facioscapulohumeral muscular dystrophy, even in the absence of cardiac symptoms. C As per AAN 2015 guidelines, avoid obtaining routine screening cardiac tests without signs or symptoms of cardiac disease. Refer patients for cardiac evaluation if they develop overt signs or symptoms of cardiac disease. D Hearing evaluation: obtain screening for hearing loss in all young pediatric patients with facioscapulohumeral muscular dystrophy at diagnosis, and yearly thereafter until patients start https://web.pathway.md/diseases/recgxQZ5z8X0KSiPX 2/4 6/29/23, 4:00 AM Facioscapulohumeral muscular dystrophy Pathway school, as hearing loss may not be present at diagnosis and can be progressive. B Retinal evaluation: refer patients with facioscapulohumeral muscular dystrophy and large deletions (contracted D4Z4 allele of 10-20 kb) to an experienced ophthalmologist for dilated indirect fundoscopy. Use the presence and severity of retinal vascular disease at the initial screening to determine the frequency of subsequent monitoring. B 3. Respiratory support Airway clearance: consider offering glossopharyngeal breathing for lung volume recruitment and airway clearance in patients with hypoventilation. C Show 4 more Noninvasive ventilation: initiate noninvasive ventilation in patients with chronic respiratory failure. B Show 4 more Invasive ventilation: consider offering invasive home mechanical ventilation via tracheostomy as an alternative to noninvasive ventilation in patients failing or intolerant of noninvasive ventilation (including extended daytime noninvasive ventilation use), worsening bulbar function, frequent aspiration, insufficient cough, episodes of chest infection despite adequate secretion management, or declining lung function. C 4. Medical management Management of strength: avoid using albuterol, corticosteroids, or diltiazem to improve strength in patients with facioscapulohumeral muscular dystrophy. D Management of pain: inquire about pain routinely in patients with facioscapulohumeral muscular dystrophy. B Show 2 more 5. Nonpharmacologic interventions Aerobic exercises: consider encouraging patients with facioscapulohumeral muscular dystrophy to engage in low-intensity aerobic exercise programs, guided by experienced physical therapists. C 6. Surgical interventions Scapular fixation: consider performing surgical scapular fixation cautiously in selected patients after careful consideration of the overall muscle impairment in the involved arm, assessment of potential gain in the ROM by manual fixation of the scapula, the patient's rate of disease progression, and the potential adverse consequences of surgery and prolonged post- surgical bracing. C https://web.pathway.md/diseases/recgxQZ5z8X0KSiPX 3/4 6/29/23, 4:00 AM Facioscapulohumeral muscular dystrophy Pathway Clinical findings Symptoms Past medical history Facial weakness Abdominal muscle weakness Loss of balance Ocular exam Lower leg weakness Myalgia Retinal abnormalities Neurological exam Musculoskeletal exam Beevor's sign Asymmetrical limb weakness Impaired balance on one foot Foot drop Inability to wALK on heels Hip weakness Lordosis Head and neck exam Quadriceps atrophy Hearing loss Shoulder weakness Winging of the scapula Genetic testing Shortening of the repeated DNA elements within the 4q35 region of chromosome 4 References 1. J M Burgunder, L Sch ls, J Baets et al. EFNS guidelines for the molecular diagnosis of neurogenetic disorders: motoneuron, peripheral nerve and muscle disorders. Eur J Neurol. 2011 Feb;18 2 207 217. Open 2. Tawil R, Kissel JT, Heatwole C et al. 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. Open 3. Akram Khan, Lindsy Frazer-Green, Reshma Amin et al. Respiratory Management of Patients with Neuromuscular Weakness: An American College of Chest Physicians Clinical Practice Guideline and Expert Panel Report. Chest. 2023 Mar 13;S0012 3692 23 00353 7. Open 4. William J Groh, Deepak Bhakta, Gordon F Tomaselli et al. 2022 HRS expert consensus statement on evaluation and management of arrhythmic risk in neuromuscular disorders. Heart Rhythm. 2022 Oct;19 10):e61-e120. Open 5. Jeffrey Statland, Rabi Tawil. Facioscapulohumeral muscular dystrophy. 2014 Aug;32 3 721 8, ix.2014 Aug;32 3 721 8, ix. Open 6. Jeffrey M. Statland, Rabi Tawil. Facioscapulohumeral Muscular Dystrophy. Continuum Minneap Minn). 2016 Dec 5; 22 6 1916 1931. Open 7. Jeffrey M. Statland, Rabi Tawil. Facioscapulohumeral Muscular Dystrophy. Neurol Clin. 2014 Aug; 32 3 721 ix. Open https://web.pathway.md/diseases/recgxQZ5z8X0KSiPX 4/4