FACIOSCAPULOHUMERAL MUSCULAR DYSTROPHY

·         AD (Autosomal Dominant)

·         a.k.a. Landouzy-Dejerine disease

·         Two types- FSHD1 (95%) & FSHD2 (5%) [clinically and histopathologically identical]

·         Genetics-

§  Shows genetic anticipation phenomenon.

§  Locus- 4q35 (intragenic tandem repeats deletions)→ DUX4 gene toxic, aberrant expression

§  Associated translocations of 10q26 maybe present

·         Clinical manifestations

§  Onset - children or young adults

§  Initial manifestation- facial weakness

§  Facial weakness-

§  Rounded mouth with protruding upper and lower lips

§  Inability to close eyes

§  Weakness of extraocular muscles

§  Shoulder Girdle weakness-

§  Wingingof scapula – prominent (maybe seen in infants)

§  Atrophyof humeral muscles – characteristic

§  Weakness during wrist extension > wrist flexion

§  Hip Girdle and Lower limb weakness-

§  Gower’s sign and Trendelenburg gait maybe seen

§  Weakness of anterior tibial and peroneal muscles → foot drop

§  Hypertrophy not seen

§  SNHL (sensorineural hearing loss)

§  Coat’s disease

·         Lab features and Diagnosis

§  Serum CK – normal/↑

§  Electromyography (EMG) – nonspecific features of myopathy

§  Muscle biopsy-

§  Proliferation of connective tissue between myofibrils

§  Non-specific inflammatory infiltrate (esp. mononuclear cell infiltrate)

§  Degenerating and regenerating myofibrils

·         Treatment-

§  No specific treatment available

§  No role of physiotherapy

§  Supportive treatment-

§  Ankle-foot orthoses – foot drop

§  Scapular stabilization