Exactly! This doesn't mean all practicioners of any art are quacks as the
allopaths would have us believe.

They never judge themselves by the same standards used to intimidate the
public against contrary practices to their own.

And yet many of these selfproclaimed  "professionals" secretly participate
in the "dark" arts for their own health.

Well, nasty things can happen very occasionally:
J

     Neurol Med Chir (Tokyo). 2000 Apr;40(4):211-5. Related Articles, Links

Spontaneous vertebral arteriovenous fistula--case report.

Yoshida S, Nakazawa K, Oda Y.

Department of Neurosurgery, Kobe City General Hospital.

A 57-year-old male presented with a rare case of spontaneous vertebral
arteriovenous fistula manifesting as radiculopathy of the right arm,
subsequently associated with pulsating tinnitus and vascular bruit in the
nape. He had a past history of chiropractic-induced vertebrobasilar
infarction. Angiography showed a simple and direct fistula between the third
segment of the right vertebral artery and the epidural veins at the C-1
level, where the artery runs backward above the arch of the C-1 just
proximal to the penetration of the dura. The fistula was successfully
obliterated by coil embolization, resulting in rapid improvement of the
signs and symptoms. Mechanical compression to the nerve roots by the
engorged epidural veins with arterial pressure was considered to be the
major cause of radiculopathy. Vertebral artery dissection induced by
chiropractic manipulation is most likely responsible for the development of
the fistula.