—Here the anterior part of the foot is drawn backward and the plantar arch made much more prominent. It may even be converted into a Gothic arch. Extremes of this type are seen in the feet of Chinese women. One form is due to contraction of the peroneus longus, owing to paralysis of the sural muscles, by which the long flexors are permitted to work to extra advantage; and yet another form is often of congenital origin, having its explanation in paralysis of the interossei and other small intrinsic muscles of the foot ([Fig. 267]).
When an ordinary metal sole plate fails to give relief a subcutaneous or open division of the contracted structures may be practised.
CONGENITAL MISPLACEMENT (DISLOCATION) OF THE HIP.
Perhaps a more proper name for this congenital deformity would be “misplacement” rather than dislocation. It is seen much oftener in females than in males. It may be either unilateral or bilateral. The displacement is usually upward and backward upon the dorsum of the ilium. In rarer instances it is anterior and sometimes the head of the femur lies not far away from the anterior superior spine of the ilium.
Regarding its cause absolutely nothing is known. It represents defective development rather than arrest, and is a condition of intra-uterine life. The acetabulum is usually found incomplete, but whether this is the cause of the misplacement or whether it fails to develop because of the absence of the head of the femur from this cavity it is not easy to decide. The influence of heredity in these cases is undeniable, for it is known to have prevailed in certain families. Thirty years ago but little was known in regard to the affection, and nothing could be done to atone for it. Of late years it has been the subject of special study by numerous investigators ([Figs. 268] and [269]).
Fig. 268
Double congenital displacement of the hip. Buffalo Clinic. (Skiagram by Dr. Plummer.)
Fig. 269
