The study of calcium, phosphorus, hydroxyproline, and nitrogen in decompensated coxarthroses and gonarthroses.

A study was undertaken to find our the biological profile of bone symptomatology of decompensated coxarthrosis and gonarthrosis. In a group of 77 patients and in 48 individual patients the levels of calcium, phosphorus, hydroxyproline and nitrogen were studied for four successive days. Calcium was administered by the intravenous route on the third day (186 mg). The results were compared to 16 healthy controls. Analysis was made with reference to the differences in sex, age, stature and anabolic therapy. The products eliminated were referred in absolute amounts to the body surface and to the period of 1 minute. 91 patients and 17 healthy controls were subjected to a provoked hypercalciuria test. Five patients were followed up in a 47Ca kinetic study and its result was compared to the content of Ca/P and P/Ca in serum and urine found in the same patients and in 21 healthy controls. The biological profile was also compared to a group of patients with gonarthrosis and varose deformity and to 127 patients with inflammatory joint diseases. From the results it is assumed that in women with decompensated coxarthrosis and gonarthrosis the syndrome of disease is a bone manifestation which affects the mineral bone substrate and particularly its calcium level. Phosphorus and the organic products of bone (nitrogen and hydroxyproline) of these patients are susceptible to intravenous administration of calcium. In women the metabolism of collagen appears to be more active than that seen in controls, and tends to resemble that of phosphorus. With its lower activity calcium tends to relate to noncollagenic products, such as osseomucoid (glycoprotein, proteoglycan) and osseoalbumoid. In accord with the findings, the patients show a higher miscible pool of calcium (47Ca), and its lower elimination (in urine and stools) and lower accretion to bone. There are a number of factors (sex, stature, age, clinical compensation of disease) that must be taken into consideration when evaluating the results.