The transverse forefoot arch demonstrated by a novel X-ray projection.

OBJECTIVE: Metatarsalgia is often treated by metatarsal osteotomy. Exact knowledge of the normal anatomy of the forefoot is essential for pre-operative planning. The objective of this study was to investigate the forefoot arch during maximal loading in a randomly selected population sample. METHODS: Two hundred subjects randomly selected from a municipality representative of Denmark were invited to interview and forefoot X-ray examination, including a novel horizontal X-ray projection by which the height of each metatarsal from the floor can be measured under maximal loading. RESULTS: One hundred and thirty-four subjects (79%) presented themselves for interview and X-ray examination. The study group was representative of the randomly selected population sample in terms of age, sex and incidence of metatarsalgia. The study verified that the interrelated geometry of the metatarsal heads in the AP plane corresponds to a parabola as suggested previously (Le Lièvre's parabola). Also in the horizontal plane, the metatarsal heads generally form an arch, the transverse forefoot arch (TFA). Mean height was 3.91mm (S.E.=0.10). The individual height of the TFA varied from -1 to 10mm and was dependent on the width of the forefoot. The relative height of the arch (arch height divided by forefoot width) was independent of age and sex. A non-significant tendency towards a lower arch among subjects with metatarsalgia was observed. CONCLUSION: This population study demonstrated that the metatarsal heads constitute arches in both planes (Le Lièvre's parabola in the AP plane and the transverse forefoot arch in the horizontal plane). This knowledge is essential for pre-operative planning in metatarsal osteotomy for metatarsalgia. Formulae for calculating the individual location of each metatarsal head were obtained.

Familial tendency to foetal loss analysed with Bayesian graphical models by Gibbs sampling.

This paper presents several models for investigating whether the HLA allogenotypes DR1/Br, DR3 and DR10 are genetic markers for a predisposition of experiencing unexplained recurrent foetal losses. A total of 199 women from 113 families answered questionnaires concerning their pregnancies and 145 of these women were HLA typed. The analysis of the data is complicated as dependencies between pregnancy outcomes are expected. The main purpose of the paper is to illustrate how such analyses can be performed using Bayesian graphical models and Gibbs sampling. The analyses are made using the programs BUGS and CODA. Markov chain Monte Carlo analyses within a Bayesian framework have become easier with the introduction of these programs. However, experience shows that some caution is required so we recommend making some initial analyses using very simple models and perhaps approximative methods, followed by a model development introducing increasing complexity.

Maternal HLA class II allogenotypes are markers for the predisposition to fetal losses in families of women with unexplained recurrent fetal loss.

The HLA allogenotypes DR1/Br, DR3 and DR10 (entitled risk HLA markers) have been reported as being genetic markers for the predisposition to experience unexplained recurrent fetal losses. The aim of the study was to determine whether the putative risk HLA markers might also be markers for the risk of pregnancy loss in sisters and wives of brothers of women with unexplained recurrent fetal losses. Information concerning pregnancy outcomes among the relatives of 146 consecutive women with unexplained recurrent fetal losses was collected. Ninety-five of the full sisters, 69 of the full brothers and 50 of the wives of the brothers were HLA typed. Sisters who had experienced at least one previous pregnancy loss (affected women) shared more HLA haplotypes with the proband than unaffected sisters, when the proband was positive for the risk markers (P = 0.02). More affected than unaffected sisters and brothers' wives were positive for the risk markers (P < 0.005 and P < 0.03; respectively). The lowest estimate of the odds ratio for experiencing pregnancy loss among sisters and brothers' wives who were positive compared with those negative for the risk markers was 3.5 (95% credible interval = 1.9-5.8). It is concluded that maternal DR1/Br, DR3 and DR10 allogenotypes seem to be genetic markers for the risk of pregnancy loss among relatives of women with unexplained recurrent fetal losses. The pattern of inheritance suggests a polygenic mode of inheritance with alleles linked to the risk HLA markers interacting with non-HLA linked genes expressed on the fetus or the trophoblast.