Osteomalacia in Fractures of the Proximal Femur

Abstract

The occurrence of osteomalacia was studied in 58 hip fracture patients who were admitted to the hospital for operative treatment. Findings indicated that osteomalacia was frequent in the series. Hypocalcemia was found in 70% and an increase in serum alkaline phosphatase in 22% of the patients. Urinary Ca excretion decreased in 45% and urinary hydroxyproline excretion increased in 70% of the cases. The serum levels of 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D were significantly decreased in the patients compared with the controls. Histomorphometric analysis revealed no difference in the amount of trabecular bone in the patients compared with the controls, but the amount of osteoid and resorption surfaces was increased in the patients. Histological osteomalacia was found in 12 out of 50 patients (24%). In 10 of these 12 cases the diagnosis of osteomalacia was supported by biochemical changes. There was only 1 patient, a 29-yr-old man with gluten enteropathy who had an evident reason for osteomalacia. The most obvious cause of osteomalacia was the lack of vitamin D due to a deficient diet and lack of exposure to sunlight. Osteoporosis was the main cause and osteomalacia was an important aggravating factor in the bone fragility in these hip fracture patients.