Femoral neck cortical geometry measured with magnetic resonance imaging is associated with proximal femur strength.

INTRODUCTION: Magnetic resonance imaging (MRI) is a promising medical imaging technique that we used to assess femoral neck cortical geometry. OBJECTIVES: Our primary objective was to assess whether cortical bone in the femoral neck assessed by MRI was associated with failure load in a simulated sideways fall, with and without adjustment for total bone size. Our secondary objective was to assess the reliability of the MRI measurements. MATERIALS AND METHODS: We imaged 34 human cadaveric proximal femora using MRI and dual-energy X-ray absorptiometry (DXA). MRI measurements of cross-sectional geometry at the femoral neck were the cortical cross-sectional area (CoCSA(MRI)), second area moment of inertia (x axis; Ix(MRI)), and section modulus (x axis; Zx(MRI)). DXA images were analyzed with the standard Hologic protocol. From DXA, we report the areal bone mineral density (aBMD(DXA)) in the femoral neck and trochanteric subregions of interest. The femora were loaded to failure at 100 mm/s in a sideways fall configuration (15 degrees internal rotation, 10 degrees adduction). RESULTS AND OBSERVATIONS: Failure load (N) was the primary outcome. We observed that the femoral neck CoCSA(MRI) and Ix(MRI) were strongly associated with failure load (r (2)=0.46 and 0.48, respectively). These associations were similar to those between femoral neck aBMD and failure load (r (2)=0.40), but lower than the associations between trochanteric aBMD and failure load (r (2)=0.70). CONCLUSION: We report that MRI holds considerable promise for measuring cortical bone geometry in the femoral neck and for predicting strength at the proximal femur.

[X-linked lymphoproliferative syndrome]. / Het X-gebonden lymfoproliferatieve syndroom.

This report deals with the case history of a 21/2-year old Turkish boy, who died from an overwhelming mononucleosis infectiosa. The parents, first cousins, lost already two sons and a daughter. According to the parents, the symptoms of these children resembled those of this boy. In the patient, described here, an acquired immunodeficiency was found, probably induced by the Epstein-Barr virus on the basis of a genetic susceptibility for this virus. The family history, the clinical picture, together with the serological, immunological - and histological examinations, pointed to the diagnosis of X-linked recessive lymfoproliferative syndrome (XLP), as described by Purtilo. The immunological findings resemble those of AIDS (acquired immunodeficiency syndrome).

Acute disseminated histiocytosis-X: in situ immunophenotyping with monoclonal antibodies.

The proliferating skin cells in a case of acute disseminated histiocytosis-X (Abt-Letterer-Siwe disease) confirmed by electron microscopy, were characterized by a panel of monoclonal antibodies using an immunoperoxidase technique. The "histiocytes" were found to stain with OKT-6 (anti-T6) and anti-HLA-DR antibodies. Unexpectedly, slight staining was also observed with Leu 3a (anti-T4) and OKM-1. A proliferative process of T4, T6, HLA-DR, OKM-1 positive Langerhans' cells has not yet been described and may be specific for histiocytosis-X.

[Pulmonary alveolar microlithiasis in 2 Moroccan sisters]. / Pulmonale alveolaire microlithiasis bij twee Marokkaanse zusjes.

The histories of two Moroccan sisters with pulmonary alveolar microlithiasis are described. Two years follow-up is available. The elder girl has no complaints, her two years younger sister becomes dyspnoeic on exercise. Pulmonary alveolar microlithiasis is a rare condition, which occurs mostly as a familiary disease. On pathologic examination characteristic calcifications are found in the alveoli. The radiographic picture of the chest is quite typical. A short review of the literature is presented.

Immunocompetent cells in psoriasis. In situ immunophenotyping by monoclonal antibodies.

Immunocompetent cells in exacerbating untreated psoriasis vulgaris skin lesions were immunophenotypically studied by the application of a selection of monoclonal antibodies in a two-stage immunoperoxidase technique. Epidermal changes include: focal accumulation of immunoglobulins in the stratum corneum, as demonstrated by a mixture of monoclonal anti-kappa and anti-lambda antibodies; focal accumulation of OKM-1 positive but Mo-2 negative cells high in the epidermis, reflecting granulocytes in Munro's abscesses; a marked decrease in epidermal Langerhans cells with focal abnormal clumping and smaller dendrites, as demonstrated by monoclonal anti-HLA-DR and anti-T6 (OKT-6) antibodies; and, sporadic exocytosis of mainly T1 (Leu-1), T8 (Leu-2a) positive suppressor/cytotoxic T lymphocytes. The dermal infiltrates were found to consist mainly of partically activated T1 (Leu-1), T4 (Leu-3a) positive T-helper/inducer cells with a smaller compartment of T1 (Leu-1), T8 (Leu-2a) positive suppressor/cytotoxic lymphocytes. These cells were found in close apposition to T6 (OKT-6), HLA-DR positive Langerhans cells and further accompanied by a minor compartment of OKM-1, Mo-2 positive monocytes. No B-cells or plasma cells could be demonstrated in the dermis. Natural killer cells were observed only incidentally. These results fit best with the hypothesis that psoriasis is a chronic inflammatory condition as a result of persistent stimulation of T cells by immunogen(s) of epidermal origin.

Heterotopic nervous tissue in the lungs.

Foci of heterotopic nervous tissue, including ganglion-cells, were found in the lungs of an anencephalic foetus. The nine cases in the literature are reviewed. Only in two of these cases was the histological investigation sufficiently detailed to establish the nature of the ectopic tissue. In all but one case the condition was associated with gross malformation of the brain.

Appraisal of the dislocation of central venous catheter tips using subclavian and arm veins.

The most dramatic of the complications resulting from central venous catheterization is perforation of the heart. We studied the complications reported in the literature and undertook an original investigation of the dislocations of peripherally and infraclavicularly inserted catheters while moving the arm and shoulder in patients during autopsy. In a postmortem examination of three patients it was found that the greatest displacement, up to eight centimetres, of the tips of the catheters occurred when they were inserted through the basilic vein. The tips of infraclavicular inserted catheters did not move at all during movements of the arm. Only by extreme movements of the shoulder we were able to show a maximal displacement of two centimetres. Advancement of the catheter tip occurred during adduction and flexion of the elbow joint and not during abduction. Our experimental evidence suggests that the best site for a catheter tip is the upper part of the right atrium. We therefore recommend the subclavian route for in-dwelling central venous catheters rather than insertion through an arm vein, as this minimizes the risk of cardiac perforation due to its great stability.