The spine may be curved backwards—­kyphosis—­throughout its whole extent or only in one part; or it may be curved to one side—­scoliosis.

In the limbs, the prominent features are the deficient growth in length of the long bones, the enlargements at the epiphysial junctions, and the bending, and occasional greenstick fracture, of the shafts.  The degree of enlargement of the epiphysial junctions is directly proportionate to the amount of movement to which the bone is subjected (John Thomson).  The curves at this stage depend on the attitude of the child while sitting or being carried—­for example, the arm bones become bent in children who paddle about the floor with the aid of their arms; and in a child who lies on its back with the lower limbs everted, the weight of the limb may lead to curvature of the neck of the femur—­coxa vara.  The clavicle or humerus may sustain greenstick fracture from the child being lifted by the arms; the femur, by a fall.  From the extreme laxity of the ligaments, the joints can be moved beyond the normal limits, and the child is often observed to twist its limbs into abnormal attitudes.

In Children who have walked.—­In these children the most important deformities occur in the spine, pelvis, and lower extremities, and result for the most part from yielding of the softened bones under the weight of the body.  Scoliosis is the usual type of spinal curvature, and in extreme cases it may lead to a pronounced form of hump-back.  The pelvis may remain small (justo-minor pelvis), or it may be contracted in the sagittal plane (flat pelvis); when the bones are unusually soft, the acetabular portions are pushed inwards by the femora bearing the weight of the body, and the pelvis assumes the shape of a trefoil, as in the malacia of women.  The shaft of the femur is curved forwards and laterally; the bones of the leg laterally as in bow-leg, or forwards, or forwards and laterally just above the ankle.  The deformities at the knee (genu valgum, genu varum, and genu recurvatum), and at the hip (coxa vara), will be described in the volume dealing with the Extremities.

The majority of cases seen in surgical practice suffer from the deformities resulting from rickets rather than from the active disease.  The examination of a large series of children at different ages shows that the deformities become less and less frequent with each year.  Those who recover may ultimately show no trace of rickets, and this is especially true of children who grow at the average rate; in those, however, in whom growth is retarded, especially from the fifth to the seventh year, the deformities are apt to be permanent.  It may be noted that the scoliosis due to rickets has little tendency towards recovery.