stricted, and
with but little impairment of function. The child should be treated
for rickets, and put up in a double long splint with the limbs
abducted and inverted.

In _arthritis deformans_ of the hip, it is not uncommon to have
considerable depression of the head of the bone and diminution in the
angle of its neck, with consequent restriction of abduction. Sometimes
the upper end of the shaft is also curved.

In _osteomyelitis fibrosa_, involving the upper end of the femur, a
gross form of coxa vara may be observed, of which a marked example is
shown in figures on pp. 476, 478, Volume I.

The _congenital variety_ of coxa vara is due to various intra-uterine
conditions, of which the chief is defective development of the upper
end of the femur; as it does not manifest itself until the child
begins to walk, the resemblance to congenital dislocation of the hip
is very close.

#Coxa Valga.#--Coxa valga is the reverse of coxa vara, the angle at
the neck of the femur being over 140 deg.. It is not nearly so important
in practice as coxa vara. It may result from incomplete fractures or
epiphysial separations, rickets, or various forms of osteomyelitis,
but it is also a frequent accompaniment of other deformities, such as
congenital dislocation of the hip and paralysis following anterior
poliomyelitis. It is commoner in boys than in girls, and is more often
single than bilateral. The limb is lengthened, abducted, and rotated
outwards; there is flattening of the buttock, and the trochanter is
depressed so that it lies below Nelaton's line. The patient is unable
to adduct the limb, and shows a peculiar gait, which has frequently
caused the condition to be mistaken for unilateral congenital
dislocation at the hip.

In recent cases it may be possible under anaesthesia forcibly to adduct
the limb and rotate it inwards, and to retain it in this position with
a plaster bandage. In advanced cases the length of the limbs may be
equalised by a high sole on the sound side, or by performing an
osteotomy through the great trochanter.

THE REGION OF THE KNEE

#Congenital dislocation# at the knee-joint is rare; it is usually
incomplete, and the patella is sometimes absent. The dislocation may
be permanent, or may only occur from accidental movements of the limb.
In some cases it can be produced at will by the patient or the
surgeon. We have observed one such case in a professional cyclist in
whom this capacity of partially dis