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8 | InTouch DECEMBER 2022 when rising from a chair, climbing stairs, or running. • Weakness of lower leg muscles causing instability of the ankles and difficulties in walking, particularly on uneven surfaces. • Foot drop which may result in the toes getting caught on kerbs or steps. • Absence of (or minimal) contractures even in patients with severe weakness, unlike most other muscular dystrophies. • Musculoskeletal pain originating from weakness of joint stabilizing muscles and from direct muscle inflammation. Extra muscular involvement is rare, but may include the following: • Hearing loss. • Retinal vascular disease resulting in vision loss. • Mild cardiac conduction abnormalities may be present, but FSHD is not associated with cardiomyopathy or ventricular arrhythmias as with some other muscular dystrophies. • Respiratory involvement is uncommon, but those with severe disease may have restrictive lung disease related to weakness of core and/or hip girdle muscles. • FSHD does not cause impairment of intellect or cognition, but hearing loss, if present, can affect learning or language development. Diagnosis There are often difficulties in diagnosing FSHD, as signs and symptoms of the disease vary. However, once FSHD is suspected, diagnostic tests are available to FACIOSCAPULOHUMERAL MUSCULAR DYSTROPHY (FSHD) establish a definite diagnosis. These may include: DNA Testing Genetic testing for FSHD is widely available and highly accurate. Laboratory technicians can extract DNA from a small amount of blood and detect the DNA alteration responsible for the disease. DNA testing can be done during pregnancy to determine if the fetus has inherited the gene for FSHD but cannot be used to accurately predict the severity of the condition. Creatine Kinase (CK) A blood test can assess the quantity of a muscle enzyme called creatine kinase (CK). The CK values in FSHD are normal or modestly elevated. A value examined microscopically. This can give important information on the condition of the muscle and can help to rule out other diagnoses or aid in confirming the diagnosis of FSHD. Other tests may include nerve conduction studies, hearing tests, and/or tests of cardiac function. Soon after the diagnosis of FSHD is made within a family, it is essential that genetic counselling is arranged. Genetic counsellors are a wealth of information and can provide insight into the inheritance of the disease and explain other possible diagnostic tests including prenatal testing. Genetic services in NZ are available and a referral can be made by the MDA. There is currently no cure or disease-modifying therapy for FSHD, though this is an area under active investigation. that is more than 10x normal is likely to be the result of a different form of muscle pathology and not FSHD. Electromyogram (EMG) An EMG measures the electrical activity of muscles at rest and during contraction. The results are nonspecific but may show both nerve and muscle involvement, which is typical of FSHD. Muscle Biopsy If FSHD is suspected, but the genetic testing is inconclusive, a muscle biopsy may be done as a further diagnostic step. While under a local anesthetic, a small amount of muscle tissue is taken with a needle, usually from the thigh. Using special staining techniques in the laboratory, the muscle tissue is Progression and prognosis As mentioned, symptom onset in people with FSHD varies widely but is most common in the second or third decade of life. Muscle weakness tends to progress slowly and there may be long periods with relatively little change. Many remain fully independent or minimally disabled, but about 20% of patients will require the use of a wheelchair by age 50. As life-threatening cardiac or respiratory problems are rare, FSHD does not typically influence longevity. Management There is currently no cure or disease-modifying therapy for FSHD, though this is an area under active investigation. It is possible,