||Cribra femora is a porous lesion on the anterior aspect of the femoral neck, which is the same as Allen’s fossa, but different from Poirier’s facet and plaque formation. Currently, this porosity remains highly debated as to its association with other skeletal lesions, and as to its cause. Therefore, this thesis asks two questions; what is the cause or causes of cribra femora, and to what other porous lesions is cribra femora correlated? To answer these questions, two skeletal collections were studied; the 17th-19th century, Dutch farming community Middenbeemster (n = 210), and the 1960-1975 Dutch medical Dankmeijer collection (n = 68). Both collections were examined for the presence of cribra femora, cribra orbitalia, cribra humeris, porotic hyperostosis, and cribra fibular. Further, lateral vault porosity, rickets, tuberculosis, osteoarthritis of the hip, enamel hypoplasia, growth stunting and adult stature were recorded. Cribra femora was present in 36.2% of Middenbeemster individuals and 10.3% of the Dankmeijer collection. This difference was not statistically significant. Presence and severity of cribra femora significantly increase with age into the juvenile group (7-12 years old) after which they decrease, although adults of all ages are affected. The lesion is correlated with cribra orbitalia and cribra fibular, but not with cribra humeris, providing no support for the existence of a ‘cribrous syndrome’. Cribra femora is not a nonmetric trait, since healing lesions and different degrees of lesion severity were encountered. Also, it is not the result of activity, since it occurs mostly in subadults, and is negatively correlated with osteoarthritis of the hip joint. Cribra femora is not the result of rickets, as the two are not correlated. Cribra femora is not solely the result of growth, since it occurs frequently in adults, including old adults (50+). Healing lesions and lesions of varying severity in adults indicate that lesions still form in this age group. However, cribra femora is related to a younger age, as it occurs more frequently in subadults. This is due to the thinner cortical bone and higher remodelling rates of subadults. Cribra femora is caused by systemic physiological stress, since it is positively correlated with growth stunting and is more common in populations of low socioeconomic status with high rates of infectious disease. This physiological stress resulting in cribra femora is probably anemia, which can have many causes. At Middenbeemster, cribra femora and cribra orbitalia are positively correlated. In the literature, both lesions have the same microscopic appearance. Also, cribra femora and lateral vault porosity are positively correlated, indicating that, cribra femora can form as the result of anemia in scurvy. Lastly, cribra femora is observed at higher percentages in populations experiencing more infectious disease, which may cause anemia. Thus, it can be concluded that cribra femora is caused by anemia, to which children react more severely due to their thinner cortical bone and higher remodelling rates. Still, more research is needed to solidify this conclusion.