, or domestic
servant. To enable him to stand with the least effort for long
periods, the patient adopts an attitude which makes little demand on
the muscles, and throws nearly all the strain of the body weight on
the ligaments and bones of the feet. This, which has been called "the
attitude of rest," consists in standing with the limbs apart, the
knees slightly flexed, the legs slightly rotated laterally at the
knee, and the feet pronated, with the toes pointing laterally. The
most important local factors predisposing to flat-foot are weakness of
those muscles which normally support the ankle and the tarsal arches,
especially the tibiales; weakness of the ligaments of the foot; and
softness of the tarsal bones. When these conditions are present and a
faulty method of standing and walking is adopted, the undue strain to
which the tendons and ligaments are exposed results in their being
stretched; the bones are altered in position, and flat-foot results.
The head of the talus is displaced medially, and is protruded between
the calcaneus and navicular, tending to separate them from one
another, stretching the inferior calcaneo-navicular ligament and
causing the anterior part of the foot to be abducted. The plantar
ligaments--especially the inferior calcaneo-navicular--are stretched
and lengthened. In something like 80 per cent. there is the combined
deformity--pes plano-valgus--in those who apply for treatment.

[Illustration: FIG. 153.--Flat-foot, showing loss of arch.]

_Clinical Features._--The patient complains of being easily tired, and
of pain in the foot after walking or standing. There is generally more
pain before the appearance of the deformity than when it has
developed, and at this stage it is not so easily recognised, and is
apt to be called "rheumatism." The most common seat of pain is at the
medial border of the foot behind the tubercle of the navicular, and
this is due to stretching of the inferior calcaneo-navicular ligament.
Pain is also complained of in the middle of the dorsum across the
instep, from stretching of the interosseous ligaments. Later, there is
pain over the greater process of the calcaneus in front of the lateral
malleolus, from these bones coming into contact. There may be
nocturnal cramp in the muscles of the leg and foot.

The faulty attitude of the foot in standing and walking is usually
evident. The foot appears longer and broader than normal, and when the
body weight is put on it