MATURATION CURVE OF THE SONOGRAPHIC ALPHA -ANGLE ACCORDING TO GRAPH WITHIN THE 1ST YEAR OF LIFE

In addition to Graf's classification into different hip-types a matura tion-curve of the sonographic alpha-angle was established in order to optimize the differentiation between mature hip joints and those ones which need follow-up and those ones which need treatment at any time w ithin the first year of life. The results obtained are confirming our present knowledge about the spontaneous maturation of physiolo0gically immature hip joints: The mean-value of the alpha-angle crosses the 60 degrees-borderline at about the age of two months, then reaches an ab out 64 degrees-level at about four months. This 64-degrees-level is mo re or less unchanged up the end of the first year of life.