In order to investigate the ultrastructure of bone resorptive cells in the two types of adult benign human osteopetrosis, iliac crest biopsies were obtained from 11 patients and 10 normal males, who served as a control group. Six patients had the radiological type I (4 women, 2 men, aged 23-58 years, mean = 36.5 years), and 5 type II disease (5 men, aged 20-48 years, mean = 29.8 years). The normal controls (aged 23-48 years, mean 34.1 years) were recruited from the medical staff. The biopsies were immediately divided. From each patients, half was embedded in paraffin for histochemistry and light microscopy, and half in epon for transmission electron microscopy. The osteoclasts were markedly reduced in number and size in Type I disease (0.2 +/- .7 cells vs. 2.9 +/- 1.0 cells per 2.7 mm2 of bone area, p < 0.01) compared to controls, and stained only weakly for tartrate-resistant acid phosphatase (TRAP). At the ultrastructural level, no signs of active bone resorption were identified, whereas numerous mononuclear cells were observed at the bone surfaces. In type II disease, the osteoclasts were large and highly multi-nucleated, with an increased number (8.3 +/- 2.3 cells vs. 2.9 +/- 1.0. cells per 2.7 mm2 of bone area, p < 0.01) compared to controls. In all patients with this type, but never in type I or in the controls, a smooth, TRAP-positive substance was seen between the osteoclasts and the bone surface. Ultrastructurally, this substance was amorphous, with a condensation along the cell membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Thermal stability of cortical bone collagen in relation to age in normal individuals and in individuals with osteopetrosis.

The thermal stability of cortical bone collagen was determined in iliac crest biopsies obtained from 41 normal individuals (21 women aged 20-96 years and 20 men aged 21-84 years) and 8 individuals with autosomal dominant osteopetrosis type I (4 women and 4 men aged 17-63 years). The cortical bone was decalcified and the bone matrix was cut into 80-microns-thick freeze sections parallel to the bone surface. Circular specimens punched out from the sections were used for determination of area shrinkage during gradual heating and shrinkage temperature, Ts (representing the temperature for 50% of the area shrinkage). In normal men, Ts was not found to decrease until the age of 60-65 years, but was markedly decreased in the elderly individuals. In normal women, Ts varied considerably throughout the age range tested, without relationship to age. In contrast to age-matched controls, Ts decreased with age in men with osteopetrosis, whereas Ts in affected women was neither related to age nor different from the highly variable values found in age-matched normal women. Previous findings in rats indicate that Ts decreases with the chronological age of the bone collagen. The present results agree with these findings, which imply that a reduction in turnover rate of bone results in an increasing age and a reduced Ts of the constituent collagen. Following this assumption, the turnover rate of bone seems to be more variable in women than in men and reduced in osteopetrotic men.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Bilateral femoral head dysplasia and osteochondritis. Multiple epiphyseal dysplasia tarda, spondylo-epiphyseal dysplasia tarda, and bilateral Legg-Perthes disease.

Multiple epiphyseal dysplasia tarda (MEDT) and spondylo-epiphyseal dysplasia tarda (SEDT) are genetically transmitted conditions affecting the hips, which may resemble bilateral Legg-Perthes disease (LPD). Misdiagnoses are not uncommon, with serious implications for treatment, prognosis and genetic counseling. An epidemiologic study of MEDT and SEDT in a well-defined population of 453,921 persons in Denmark was performed. A population prevalence of 0.7 per 100,000 inhabitants with SEDT and 4.0 per 100,000 inhabitants with MEDT was found. Distinguishing features between MEDT, SEDT and bilateral LPD based on radiologic findings in the hips, other joints, and spine were ascertained. Bilateral LPD is always asymmetric, exhibits patches of increased density in the epiphyses and often metaphyseal cyst-like changes. No spinal lesion or affection of other joints is present, and the acetabula are normal. In MEDT and SEDT the capital femoral epiphyses are symmetrically flattened, fragmented and uniformly slightly sclerotic. Generalised platyspondyly is a constant finding in SEDT.

Adolescent↗