geal joints; the
plantar fascia and muscles are shortened. The footprint shows that
neither border of the foot touches the ground. The patient complains
of pain in the instep, of painful corns over the heads of the
metatarsal bones, and of difficulty in getting properly fitting
boots.

_Treatment_ should first be directed towards the equinus or calcaneus
element of the deformity, for if these are corrected the cavus
condition tends to disappear. Exercises and massage should be
persevered with, and boots without heels should be worn. The
contracted structures in the sole may require to be divided, either
subcutaneously or by the open method, as a preliminary to forcible
correction, and the hallucis tendon may be brought through the head of
the first metatarsal. In aggravated cases the talus and the heads of
the metatarsal bones may be excised.

FLAT-FOOT--PES PLANUS AND PES VALGUS

Flat-foot or splay-foot is that deformity in which there is loss of
the arch, and the foot tends to be pronated and abducted. The term
_pes planus_ is applicable when there is merely loss of the arch; _pes
valgus_ when the foot is pronated and the sole looks laterally. Of all
deformities of the foot, flat-foot is the one for which advice is most
frequently sought; it is also a common complication of other
disabilities of the foot and of the lower extremity. It is usually
bilateral, and is about twice as common in the male as in the female.
Various types are met with; they are known according to their cause,
as static, congenital, traumatic, paralytic, rachitic, rheumatic,
arthritic, gonorrhoeal, and tabetic.

[Illustration: FIG. 150.--Pes Cavus in association with Pes Equinus,
the result of Poliomyelitis.]

[Illustration: FIG. 151.--Radiogram of Foot of adult, showing the
changes in the bones in Pes Cavus.]

#Static or Adolescent Flat-foot.#--This, by far the most common and
important variety (Fig. 152), generally develops between the ages of
fourteen and twenty. It is called static because the essential factor
in its production is a disproportion between the weight of the body
and the supporting power of the arch of the foot.

[Illustration: FIG. 152.--Adolescent Flat-foot.]

It is met with in rapidly growing children or adolescents of feeble
muscular development and with long narrow feet, and those especially
who, after leaving school, begin some occupation which entails much
standing--such as that of a factory hand, message boy