tic:
the elbow is flexed and is supported by the opposite hand, while the
head is inclined towards the affected shoulder to relax the muscles of
the neck. Crepitus is elicited on bracing back the shoulders, or on
attempting to raise the arm beyond the horizontal, and these movements
cause pain. Tenderness is elicited on making pressure over the seat of
fracture, and also on distal pressure. The sternal fragment almost
invariably overrides the acromial, and can usually be palpated through
the skin; on measurement, the clavicle is found to be shortened. When
the fracture is incomplete (greenstick) or transverse, the symptoms
are less marked.

[Illustration: FIG. 14.--Fracture of Acromial End of Clavicle. Shows
forward rotation of lateral fragment, and line of fracture united by
bone.]

Fracture of the _lateral_ or _acromial third_ of the clavicle is a
common form of accident at football matches, and usually results from
direct violence, the bone being driven down against the coracoid
process, and broken as one breaks a stick over the knee. The fracture
may take place through the attachment of the conoid and trapezoid
ligaments, in which case the only symptoms are pain and tenderness at
the seat of fracture, with impaired movement of the limb. Displacement
and crepitus are prevented by the splinting action of the ligaments.

When the break is lateral to the attachment of the trapezoid ligament,
the fracture is usually transverse, and is almost always due to a fall
on the back of the shoulder--the angle between the spine and the
acromion process striking the ground. The acromial fragment rotates
forward (Fig. 14), sometimes even to a right angle, causing the tip of
the shoulder to pass forwards, and so to lie slightly nearer the
middle line. The integrity of the coraco-clavicular ligaments prevents
any marked drooping of the shoulder. It is noteworthy that the
displacement is not always evident at first.

Fractures of the _medial_ or _sternal third_ are rare, are usually
oblique, and result either from an indirect force acting in the line
of the clavicle, or, less frequently, from direct violence or muscular
action. As a rule, the deformity is insignificant, except when the
costo-clavicular ligament is torn, in which case the medial end of the
distal fragment is tilted up by the weight of the arm. The shoulder
passes downwards, forwards, and medially. When close to the sternal
end, this fracture may simulate a dislocat