Genu varum (Blount's Disease) is a deformity marked by medial angulation of the leg in relation to the thigh, an outward bowing of the legs. It is also known as bandy-leg, bowleg, bow-leg, and tibia vara. Usually there is an outward curvature of both femur and tibia, with at times an interior bend of the latter bone. more...
At birth all children are more or less bandy-legged. The child lies on its nurse's knee with the soles of the feet facing one another; the tibia and femora are curved outwards; and, if the limbs are extended, although the ankles are in contact, there is a distinct space between the knee-joints. During the first year of life a gradual change takes place. The knee-joints approach one another; the femora slope downwards and inwards towards the knee joints; the tibia become straight; and the sole of the foot faces almost directly downwards.
While these changes are occurring, the bones, which at first consist principally of cartilage, are gradually becoming ossified, and in a normal child by the time it begins to walk the lower limbs are prepared, both by their general direction and by the rigidity of the bones which form them, to support the weight of the body. If, however, the child attempts either as the result of imitation or from encouragement to walk before the normal bandy condition had passed off, the result will necessarily be either an arrest in the development of the limbs or an increase of the bandy condition.
If the child is weakly, either with rickets or suffering from any ailment that prevents the due ossification of the bones, or is improperly fed, the bandy condition may remain persistent. Thus the chief cause of this deformity is rickets. The remaining causes are occupation, especially that of a jockey, and traumatism, the condition being very likely to supervene after accidents involving the condyles of the femur. In the rickety form the most important thing is to treat the constitutional disease, at the same time instructing the mother never to place the child on its feet. In many cases this is quite sufficient in itself to effect a cure, but matters can be hastened somewhat by applying splints. When in older patients the deformity arises either from traumatism or occupation, the only treatment is surgery.
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