11. The formation of articular concretions succeeds frequently to blows
or falls received on the joint, in which case, a swelling more or
less considerable in the surrounding soft parts, showing itself from
the first, and remaining for some time, at length allows the foreign
body to be perceived, and does not, in general, disappear during the
continuance of the body in the part.
12. Sometimes no external injury contributes to the formation of the
body, and then, a spontaneous swelling precedes its detection, as
Desault observed in two patients, where nothing was known to have
concurred in the production of the disease. Constant rest increases
this swelling, while exercise and a temperate mode of life diminish it.
13. But what can be the immediate cause of these tumours? Are they,
as some allege, an aggregation or crystallization of particles of
matter conveyed into the interior of the joint by the synovia, in the
same manner as the rudiments of a stone are conveyed into the bladder
by the urine? Their organic appearance and the vessels that pervade
them, are unfavourable to such an opinion. Can they be, agreeably to
the conjecture of Theden, articular glands bruised by means of strokes
or falls? Or are they, as some authors will have it, portions of the
cartilage of the joint, detached by the same causes? How then will
their spontaneous formation be explained?
But why trouble ourselves about the cause, provided we can remedy the
effects? Nature conceals from us the means, and discloses to us nothing
but the results. Theories are fluctuating; but experience is still the
same: let us search, then, by an attention to facts, for that which we
cannot learn from first principles.
§ IV.