the ring finger and continued upwards.
Protopathic sensibility is lost over an area which varies in different
cases. Deep sensibility is usually lost over an area almost as extensive
as that of protopathic insensibility.

When the nerve is _divided at the wrist_, the adjacent tendons are also
frequently severed. If divided below the point at which its dorsal
branch is given off, the sensory paralysis is much less marked, and the
injury is therefore liable to be overlooked until the wasting of muscles
and typical _main en griffe_ ensue. The loss of sensibility after
division of the nerve before the dorsal branch is given off resembles
that after division at the elbow, except that in uncomplicated cases
deep sensibility is usually retained. If the tendons are divided as
well, however, deep touch is also lost.

Care must be taken in all these injuries to prevent deformity; a splint
must be worn, at least during the night, until the muscles regain their
power of voluntary movement, and then exercises should be instituted.

#Dislocation of the ulnar nerve# at the elbow results from sudden and
violent flexion of the joint, the muscular effort causing stretching or
laceration of the fascia that holds the nerve in its groove; it is
predisposed to if the groove is shallow as a result of imperfect
development of the medial condyle of the humerus, and by cubitus valgus.

The nerve slips forward, and may be felt lying on the medial aspect of
the condyle. It may retain this position, or it may slip backwards and
forwards with the movements of the arm. The symptoms at the time of the
displacement are some disability at the elbow, and pain and tingling
along the nerve, which are exaggerated by movement and by pressure. The
symptoms may subside altogether, or a neuritis may develop, with severe
pain shooting up the nerve.

The dislocated nerve is easily replaced, but is difficult to retain in
position. In recent cases the arm may be placed in the extended position
with a pad over the condyle, care being taken to avoid pressure on the
nerve. Failing relief, it is better to make a bed for the nerve by
dividing the deep fascia behind the medial condyle and to stitch the
edges of the fascia over the nerve. This operation has been successful
in all the recorded cases.

#The Sciatic Nerve.#--When this nerve is compressed, as by sitting on a
fence, there is tingling and powerlessness in the limb as a whole, known
as "sleeping" of the li