Metabolic bone disease: osteoporosis and osteomalacia

Calcification of entheses associated with X-linked hypophosphatemic osteomalacia

We undertook a retrospective analysis of 26 patients with X-linked hypophosphatemic osteomalacia (or rickets), whose ages ranged from 1 to 62 years and who were from 11 different kindreds, to determine the prevalence and clinical characteristics of a unique disorder of the entheses (tendons, ligaments, and joint capsules). We found a generalized involvement of the entheses, with exuberant calcification of tendon and ligament insertions and of joint capsules, in 69 per cent of the subjects. The prevalence and extent of disease increased with age but were not correlated with sex. Commonly affected sites included the hand and sacroiliac joints. Histologic evaluation in a selected patient revealed intratendinous lamellar bone but no inflammatory cells. Our observations indicate that this disorder is an integral part of X-linked hypophosphatemic osteomalacia and exhibits clinical, radiographic, and histologic characteristics that differentiate it from degenerative disorders of these tissues and seronegative spondyloarthropathies.

Osteoporosis in postmenopausal women

Eleven postmenopausal complete denture patients participated in a study to evaluate some possible predictors of osteoporosis. Most participants in the study reported a low caloric intake and consumed considerably less than the recommended daily allowances of sodium, cholesterol, calcium, fluoride, magnesium, zinc, and folic acid. Many participants in the study were taking additional daily vitamin and mineral supplements. The CCT as measured on radiographs of the second phalynx of the fifth digit of the right hand correlated linearly with the CBD corrected for soft tissue. Panoramic radiographs revealed that all individuals had severe residual ridge resorption. All serum calcium and phosphorus means were within the normal range, while more than 60% of the patients had below normal plasma levels of 25-hydroxyvitamin D. In conclusion, although based on a small sample, it appears that the diet of elderly women in New York is somewhat deficient for adequate skeletal homeostasis. Ideally, the vitamin D status of each patient should be determined and proper supplements prescribed. However, the high cost of analysis suggests that dietary analysis be used on a selected but more frequent basis. Radiation techniques for measuring skeletal porosity are also too complex to perform on a routine basis and should, like dietary analysis, be reserved for patients in whom other clinical signs and symptoms indicate metabolic bone disease.