By the late 1990s, researchers were finally beginning to understand the regions of chromosome 4 associated with FSHD.Since the publication of the unifying theory in 2010, researchers continued to refine their understanding of DUX4. With increasing confidence in this work, researchers proposed the first a consensus view in 2014 of the pathophysiology of the disease and potential approaches to therapeutic intervention based on that model.Alternate and historical names for FSHD include the following:

facioscapulohumeral disease
faciohumeroscapular
Landouzy-Dejerine disease (or syndrome or type of muscular dystrophy)
Erb-Landouzy-Dejerine syndrome

Chronology of important FSHD-related genetic research
Past pharmaceutical development
Early drug trials, before the pathogenesis involving DUX4 was discovered, were untargeted and largely unsuccessful. Compounds were trialed with goals of increasing muscle mass, decreasing inflammation, or addressing provisional theories of disease mechanism. The following drugs failed to show efficacy:

Prednisone, a steroid, based on its antiinflammatory properties and therapeutic effect in Duchenne muscular dystrophy. Oral albuterol, a β2 agonist, on the basis of its anabolic properties. Although it improved muscle mass and certain measures of strength in those with FSHD, it did not improve global strength or function. Interestingly, β2 agonists were later shown to reduce DUX4 expression. Diltiazem, a calcium channel blocker, on the bases of anecdotal reports of benefit and the theory that calcium dysregulation played a part in muscle cell death. MYO-029 (Stamulumab), an antibody that inhibits myostatin, was developed to promote muscle growth. Myostatin is a protein that inhibits the growth of muscle tissue. ACE-083, a TGF-β inhibitor, was developed to promote muscle growth.
On average, FSHD2 presents 10 year later than FSHD1. Otherwise, FSHD1 and FSHD2 are indistinguishable on the basis of weakness. Disease progression is slow, and long static phases, in which no progression is apparent, is not uncommon. Less commonly, individual muscles rapidly deteriorate over several months. Face
Weakness of the muscles of the face is the most distinguishing sign of FSHD. It is typically the earliest sign, although it is rarely the initial complaint. At least mild facial weakness can be found in 90% or more with FSHD. One of the most common deficits is inability to close the eyelids, which can result in sleeping with the eyelids open and dry eyes. The implicated muscle is the orbicularis oculi muscle. Another common deficit is inability to purse the lips, causing inability to pucker, whistle, or blow up a balloon. The implicated muscle is the orbicularis oris muscle. A third common deficit is inability raise the corners of the mouth, causing a "horizontal smile," which looks more like a grin. Responsible is the zygomaticus major muscle.Weakness of various facial muscles contributes to difficulty pronouncing the letters M, B, and P. Facial expressions can appear diminished, arrogant, grumpy, or fatigued. Muscles used for chewing and moving the eyes are not affected. Difficulty swallowing is not typical, although can occur in advanced cases. FSHD is generally progressive, but it is not established whether facial weakness is progressive or stable throughout life.