Münzenberg KJ
former Orthopädische Universitätsklinik Bonn

Four subjects are presented: 1. Mineralogy, 2. Histology, 3. Biological kinetics and 4. Three clinical pictures.
Ad 1: Because of a 43 % difference in the size of the ionic radius of calcium and magnesium only a limited integration of
magnesium into the apatite crystal of bone is possible. In magnesium excess this means smaller mineral particles, shorter
storage time in the bone, higher solubility of the crystal. A molar Mg/Ca ratio of > 0.2 in liquids inhibits the formation of
calcium phosphate.
This is different in Mg-deficiency: the individuals of apatite become somewhat larger and the water content of the
hydration cover is reduced. The consequence: More brittleness and higher vulnerability to bone fractures. Radiographical
this means concealment of the magnesium deficiency despite loss of bone substance.
(Mass absorption coefficient for CuKα: Mg = 40.9 gcm-2; Ca = 171 gcm-2.) In extreme magnesium excess of the tissue there
is forming of Newberyit (MgHPO4 · 3 H2O) outside of the bone.
Ad 2: Elevated magnesium concentration in the growing bone histologically causes derangement and disaggregation in the
germinative zone and in X-ray diffractogramm smaller and less crystalline Apatite particles, analogous to in vitro and
“congenital rachitis” after tocolytic therapy with highdose parenteral magnesium.
Ad 3: Own calculation of the biological halflife in the bone results for Mg in ca. 990 days (Calcium 2700). To determine
influx and efflux it would be necessary to integrate the differential equation 1. degree  = D − k t  with D as daily
supplemented amount of 10 mg Mg to the bone, the time t in days and k as rateconstant of 0.0007 (for a total bone mass
of ca. 4 kg). Is the daily dose 300 mg per os it only would be possible to integrate 14.3 mg Mg in the bone.
Ad 4: With the application of magnesium in three different diseases there should be demonstrated meanders, effectivity
and inexplicable things.