An intermediate type is sometimes seen, in which the peroneal spasm is so great that the foot is held abducted and everted as long as the spasm lasts (spastic flat foot.) Some symptoms of flat foot that are less generally recognized, which are of great value in diagnosis are: corns, ingrowing nails, callosities on the sole of the front of the foot, enlargement of the great-toe joint, and pain (especially at night) in the calves of the legs and backbone, which is aggravated by standing and walking. +Diagnosis.+ The diagnosis of flat foot, whether flexible or rigid, is made chiefly by inspection. The difficulty comes in the milder cases, which form the bulk of those seen, and in which the changes in form are slight. +Symptoms.+ The symptoms, as described by the patient, are the most reliable and points of tenderness under the arch or heel would help to confirm the diagnosis. Some help may be obtained from a wet impression of the foot, on a piece of paper, but the slighter cases show but little changes in the imprint. In most normal feet, the outer border of the foot touches the paper, and in flat foot, only two areas bear the weight, one on the inner side of the front of the foot, and one under the inner part of the heel. An X-ray picture is often of great assistance. The diagnosis of rheumatism is frequently made in flat foot, and is often the source of much misdirected treatment. Rheumatism should be diagnosed only in connection with unmistakable symptoms of rheumatism in the upper extremities. So-called “rheumatic” pains in the knees and hips may be secondary to flat foot. +Prognosis.+ As a rule, this condition does not recover spontaneously. Under ordinary conditions, uncomplicated cases should be at once relieved by proper treatment, and in time should be cured. Unfavorable factors are: great weight; disease of the ankle-joint; the presence of bony spurs under the os calcis. The prognosis is more favorable in young adults than in persons of advanced age. Patients, who without relief have worn the ordinary supports sold at the stores will, as a rule, manifest extreme sensitiveness as to the fit of any of the supports which may be applied. +Treatment.+ The foot must be restored and held in its normal position and measures must be adopted to quiet local irritability or inflammation, and to strengthen the muscles. The best treatment does not consist in the permanent wearing of a flat-foot support; the support should be regarded in the same light as one uses a crutch in a fracture of the leg. As a preliminary to all treatment, the use of proper shoes must be insisted upon. A shoe should be as wide in front, as the unshod foot, when bearing the weight of the body.