Myopathic facies

Myotonic dystrophy in a mother and her newborn

The term myopathic facies refers to the facial appearance of patients with facial weakness due to a myopathy. The most common myopathies that cause myopathic facies are myotonic dystrophy and facioscapulohumeral muscular dystrophy.(1,2)

In myotonic dystrophy the facial appearance is typical and recognizable at a glance - augenblickdiagnose.(3) There is bilateral ptosis. Wasting of the temporalis and masseter muscles contributes to a thin visage referred to as a hatchet face. Sternomastoid atrophy causes a pencil necked appearance. Men usually suffer from premature baldness. The illustration shows the typical facial appearance in a newly diagnosed young mother holding her hypotonic infant, who has the congenital form. The mother has bilateral ptosis, hollowed temporalis muscles and a slack lower face. The infant has ptosis and the classic “tented upper lip.”

In FSH, there is bilateral ptosis and the lower face appears slack. Eye closure is often incomplete. The lips droop tonelessly, with an involuntary protrusion of the upper lip causing a pouting appearance. The mouth loses its normal contour and looks wider and more horizontal. On smiling, the risorius pulls at the angle of the mouth, but the zygomaticus is unable to elevate the lips and the smile is transverse. Patients are not able to produce the normal facial appearance of smiling and laughter, even if they find something hilarious. The loss of facial mobility causes a glum expression. Good for playing poker but not much else. There are significant social consequences, as eloquently explained by the young lady in the video.

Video courtesy of Ms. Carden Wyckoff.

References

1. Ciafaloni E, Chinnery PF, Griggs RC. Evaluation and treatment of myopathies. 2nd edition. Oxford: Oxford University Press, 2014.

2. Brooke MH. A clinician's view of neuromuscular diseases. 2nd ed. Baltimore: Williams & Wilkins, 1986.

3. Campbell WW. Augenblickdiagnose. Semin Neurol. 1998;18(2):169-76