Fluoride concentration in bone influences periprosthetic bone mineral lossafter uncemented total hip arthroplasty

Factors influencing bone remodelling after cementless total hip arthroplast y (THA) with Parhofer prosthesis were evaluated in a longitudinal study of 18 hips in 18 patients who had undergone uncemented THA due to osteoarthrit is. Bone mineral density (BMD) in the femoral neck was determined by dual-e nergy X-ray absorptiometry (DXA) measurement performed preoperatively, in p eriprosthetic femoral regions and prospectively 2 weeks, 3, 6, 12 and 24 mo nths after operative treatment. The concentrations of calcium, magnesium, z inc, and fluoride were measured in cortical and trabecular bone samples tak en from the resected femoral head and neck. After the operation, the region al BMD decreased, but after 12 months it appeared to be stabilised. Preoper ative femoral neck BMD and the fluoride content in trabecular bone indicate d that osteopenia and lower fluoride concentrations correlated with bone de nsity reduction after THA. No other factors (age, weight, sex, calcium, mag nesium, and zinc concentrations in bone and fluoride concentration in corti cal bone) showed significant associations.