Cribra orbitalia is a porotic or sieve-like lesion in the bony orbital roof. Its cause has been the object of research and discussion since the end of the 19th century. Since about 1960, most scientists have started to agree on the hypothesis that the lesion is a result of hypertrophy of the red bone marrow, and therefore is proof of anemia. However, recent investigations showed that in some cases, the histologic bone structure does not support the diagnosis of anemia. The status of cribra orbitalia as an indicator then becomes uncertain. We carried out a histologic examination of thin-ground sections in polarized light to clarify the possible sources of orbital roof lesions in a Nubian population from Missiminia, northern Sudan (n = 333). In at least 56.5% of cribra orbitalia cases, there were no histologic features indicating changes due to anemia. Signs of other pathological conditions, such as inflammation or osteoporosis, as well as pseudopathological cases, were found.

Clinical studies indicate that genetic factors play a crucial role in primary osteoarthritis and osteoporosis. In addition, it has been suggested that these two diseases are inversely related. Within a population, one can find two sub-groups: the ''bone formers'' and the ''bone losers''. The changes to the joint surfaces used to assess adult age at death are related to the loss of bone substance and to bone formation (osteophytes). The modification of these indicators with age differs between bone formers and bone losers. Therefore, age-at-death assessment methods should make use of two standards, one for each sub-group. A preliminary study examining the possibility of distinguishing those who lose cortical bone from those who show signs of bony formation was conducted on a series of skeletons from Portugal, dating to the end of 19th century and the beginning of the 20th. Bone loss was evaluated using the cortical index (CI) of the second metacarpal on X-rays. The presence of osteophytes on dry bones was assessed macroscopically.Our study indicates that females' CI decreases with age, whereas the presence of osteophytes is strongly related to age in both sexes. But we have failed to find the inverse relationship Re´sumeD e nombreuses e´tudes de´montrent que les facteurs ge´ne´tiques jouent un roˆle crucial dans le de´veloppement de l'arthrose et de l'oste´oporose et que ces deux maladies sont inversement proportionnelles. En effet, au sein d'une meˆme population, deux groupes se distinguent: les )bone fomers* (ceux qui fabriquent de la substance osseuse) et les )bone losers* (ceux qui ont tendance a`la perdre). Or, les modifications des surfaces articulaires utilise´es pour estimer l'aˆge au de´ce`s des adultes sont lie´es a`la formation et a`la perte de substance osseuse. Par conse´quent, ces indicateurs e´voluent diffe´remment selon la cate´gorie a`laquelle l'individu appartient. Chaque me´thode devrait donc proposer deux standards diffe´rents. Pour tester cette hypothe`se, une e´tude pre´liminaire a e´te´mene´e sur une se´rie de squelettes portugais (fin du 19 ie`me /de´but du 20 ie`me sie`cle). Son objectif est de savoir s'il est possible de distinguer les )bone formers* des )bone losers*. La perte osseuse a e´te´e´value´e par l'index cortical du second me´tacarpien sur radiographies. La pre´sence d'oste´ophytes a e´te´diagnostique´e sur os sec. La relation inverse entre les oste´ophytes et la perte osseuse n'a pas e´te´de´montre´e. Par conse´quent, la tentative de distinguer les )bone losers* et les )bone formers* s'est re´ve´le´e infructueuse. Toutefois, notre e´tude indique que certains individus ne de´veloppent pas d'oste´ophytes.