Os acetabuli and mixed-type FAI. This 79yo male with a history of right hip pain for 1 month has features of both pincer and cam-type FAI. Femoral head asphericity (yellow arrow), irregular anterosuperior bump (green arrowheads), os acetabuli (yellow arrowhead) and hypertrophic acetabular rim (blue arrow).
1 The other 22 pairs are autosomes (non-sex chromosomes) and look the same for both males and females. 2  The DNA making up each of our chromosomes contains thousands of genes. 3  At the ends of each of our chromosomes are sections of DNA called telomeres.
Picture 1: Genes, chromosomes and DNA. The chromosomes (see Picture 2) numbered 1 to 22 look the same in males and females. These are called the autosomes. Pair number 23 is different in males and females and they are called the sex chromosomes. There are two kinds of sex chromosome, one called the X chromosome and one called the Y chromosome.